support autofocus / autogain in libv4l2

support autofocus / autogain in libv4l2

[Pavel Machek]

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Hi!

For focus to be useful, we need autofocus implmented
somewhere. Unfortunately, v4l framework does not seem to provide good
place where to put autofocus. I believe, long-term, we'll need some
kind of "video server" providing this kind of services.

Anyway, we probably don't want autofocus in kernel (even through some
cameras do it in hardware), and we probably don't want autofocus in
each and every user application.

So what remains is libv4l2. Now, this is in no way clean or complete,
and functionality provided by sdl.c and asciicam.c probably _should_
be in application, but... I'd like to get the code out there.

Oh and yes, I've canibalized decode_tm6000.c application instead of
introducing my own. Autotools scare me, sorry.

Regards,
							Pavel

diff --git a/lib/libv4l2/asciicam.c b/lib/libv4l2/asciicam.c
new file mode 100644
index 0000000..5388967
--- /dev/null
+++ b/lib/libv4l2/asciicam.c
@@ -0,0 +1,63 @@
+/* gcc asciicam.c /usr/lib/i386-linux-gnu/libv4l2.so.0.0.0 -o asciicam
+   gcc asciicam.c /usr/lib/arm-linux-gnueabi/libv4l2.so.0 -o asciicam
+
+gcc -std=gnu99 -DHAVE_CONFIG_H -I. -I../.. -fvisibility=hidden -I../../lib/include -Wall -Wpointer-arith -D_GNU_SOURCE -I../../include -g -O2 asciicam.c libv4l2.c /usr/lib/arm-linux-gnueabi/libv4lconvert.so.0 log.c v4l2convert.c v4l2-plugin.c -o asciicam
+ */
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include <linux/videodev2.h>
+
+#define SIZE 10*1024*1024
+
+char buf[SIZE];
+
+void main(void)
+{
+  int fd = v4l2_open("/dev/video2", O_RDWR);
+  int i;
+  static struct v4l2_format fmt;
+
+#if 1
+  fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;
+  fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
+  fmt.fmt.pix.width = 640;
+  fmt.fmt.pix.height = 480;
+  if (fmt.fmt.pix.pixelformat != 'RGB3') /* v4l2_fourcc('R', 'G', 'B', '3'); */
+    printf("hmm. strange format?\n");
+  
+  printf("ioctl = %d\n", v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt));
+#endif
+
+  for (i=0; i<500; i++) {
+    int num = v4l2_read(fd, buf, SIZE);
+    int y,x;
+    
+    printf("%d\n", num);
+#if 0
+    for (y = 0; y < 25; y++) {
+      for (x = 0; x < 80; x++) {
+	int y1 = y * 480/25;
+	int x1 = x * 640/80;
+	int c = buf[fmt.fmt.pix.width*3*y1 + 3*x1] +
+	  buf[fmt.fmt.pix.width*3*y1 + 3*x1 + 1] +
+	  buf[fmt.fmt.pix.width*3*y1 + 3*x1 + 2];
+
+	if (c < 30) c = ' ';
+	else if (c < 60) c = '.';
+	else if (c < 120) c = '_';
+	else if (c < 180) c = 'o';
+	else if (c < 300) c = 'x';
+	else if (c < 400) c = 'X';
+	else c = '#';
+	  
+	printf("%c", c);
+      }
+      printf("\n");
+    }
+#endif    
+  }
+}
diff --git a/lib/libv4l2/libv4l2-priv.h b/lib/libv4l2/libv4l2-priv.h
index 343db5e..af740a7 100644
--- a/lib/libv4l2/libv4l2-priv.h
+++ b/lib/libv4l2/libv4l2-priv.h
@@ -1,3 +1,4 @@
+/* -*- c-file-style: "linux" -*- */
 /*
 #             (C) 2008 Hans de Goede <hdegoede@redhat.com>
 
@@ -70,6 +71,14 @@
 	} while (0)
 
 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
+#define V4L2_MAX_SUBDEVS 16
+
+#define V4L2_MAX_FOCUS 10
+struct v4l2_focus_step {
+	int num;
+	int sharpness[V4L2_MAX_FOCUS];
+	int position[V4L2_MAX_FOCUS];
+};
 
 struct v4l2_dev_info {
 	int fd;
@@ -104,6 +113,14 @@ struct v4l2_dev_info {
 	void *plugin_library;
 	void *dev_ops_priv;
 	const struct libv4l_dev_ops *dev_ops;
+        int subdev_fds[V4L2_MAX_SUBDEVS];
+  	int exposure; 
+  	int frame;
+  	int focus;
+
+	/* Autofocus parameters */
+	int focus_frame, focus_exposure, focus_step, sh_prev;
+	struct v4l2_focus_step focus_step_params;
 };
 
 /* From v4l2-plugin.c */
diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
index 0ba0a88..3b84437 100644
--- a/lib/libv4l2/libv4l2.c
+++ b/lib/libv4l2/libv4l2.c
@@ -1,3 +1,4 @@
+/* -*- c-file-style: "linux" -*- */
 /*
 #             (C) 2008 Hans de Goede <hdegoede@redhat.com>
 
@@ -100,6 +101,13 @@ static struct v4l2_dev_info devices[V4L2_MAX_DEVICES] = {
 };
 static int devices_used;
 
+#include "sdl.c"
+
+static struct sdl sdl;
+
+int v4l2_get_index(int fd);
+void my_main(void);
+
 static int v4l2_ensure_convert_mmap_buf(int index)
 {
 	if (devices[index].convert_mmap_buf != MAP_FAILED) {
@@ -311,7 +319,409 @@ static int v4l2_queue_read_buffer(int index, int buffer_index)
 	return 0;
 }
 
-static int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
+static void v4l2_paint(char *buf, int x1, int y1, const struct v4l2_format *fmt)
+{
+  int y, x;
+  int width = fmt->fmt.pix.width;
+  printf("width = %d\n", width);
+    
+    for (y = 0; y < 25; y++) {
+      for (x = 0; x < 80; x++) {
+	int c = buf[width*4*y1 + 4*x1] +
+	  buf[width*4*y1 + 4*x1 + 1] +
+	  buf[width*4*y1 + 4*x1 + 2];
+
+	if (c < 30) c = ' ';
+	else if (c < 60) c = '.';
+	else if (c < 120) c = '_';
+	else if (c < 180) c = 'o';
+	else if (c < 300) c = 'x';
+	else if (c < 400) c = 'X';
+	else c = '#';
+	  
+	printf("%c", c);
+      }
+      printf("\n");
+    }
+}
+
+#define SX 80
+#define SY 25
+#define BUCKETS 20
+
+static void v4l2_histogram(unsigned char *buf, int cdf[], struct v4l2_format *fmt)
+{
+    for (int y = 0; y < fmt->fmt.pix.height; y+=19)
+      for (int x = 0; x < fmt->fmt.pix.width; x+=19) {
+	pixel p = buf_pixel(fmt, buf, x, y);
+	
+	int b;
+	/* HACK: we divide green by 2 to have nice picture, undo it here. */
+	b = p.r + 2*p.g + p.b;
+	b = (b * BUCKETS)/(256);
+	cdf[b]++;
+      }
+}
+
+static long v4l2_sharpness(unsigned char *buf, struct v4l2_format *fmt)
+{
+  int h = fmt->fmt.pix.height;
+  int w = fmt->fmt.pix.width;
+  long r = 0;
+
+    for (int y = h/3; y < h-h/3; y+=h/9)
+      for (int x = w/3; x < w-w/3; x++) {
+	pixel p1 = buf_pixel(fmt, buf, x, y);
+	pixel p2 = buf_pixel(fmt, buf, x+2, y);
+	
+	int b1, b2;
+	/* HACK: we divide green by 2 to have nice picture, undo it here. */
+	b1 = p1.r + 2*p1.g + p1.b;
+	b2 = p2.r + 2*p2.g + p2.b;
+
+	int v;
+	v = (b1-b2)*(b1-b2);
+	if (v > 36)
+		r+=v;
+      }
+
+    return r;
+}
+
+int v4l2_set_exposure(int fd, int exposure)
+{
+	int index = v4l2_get_index(fd);
+
+	if (index == -1 || devices[index].convert == NULL) {
+		V4L2_LOG_ERR("v4l2_set_exposure called with invalid fd: %d\n", fd);
+		errno = EBADF;
+		return -1;
+	}
+
+	struct v4l2_control ctrl;
+	ctrl.id = V4L2_CID_EXPOSURE;
+	ctrl.value = exposure;
+	if (ioctl(devices[index].subdev_fds[0], VIDIOC_S_CTRL, &ctrl) < 0) {
+	  printf("Could not set exposure\n");
+	}
+	return 0;
+}
+
+int v4l2_set_gain(int fd, int gain)
+{
+	int index = v4l2_get_index(fd);
+
+	if (index == -1 || devices[index].convert == NULL) {
+		V4L2_LOG_ERR("v4l2_set_exposure called with invalid fd: %d\n", fd);
+		errno = EBADF;
+		return -1;
+	}
+	
+	struct v4l2_control ctrl;
+	ctrl.id = 0x00980913;
+	ctrl.value = gain;
+	if (ioctl(devices[index].subdev_fds[0], VIDIOC_S_CTRL, &ctrl) < 0) {
+	  printf("Could not set exposure\n");
+	}
+	return 0;
+}
+
+int v4l2_set_focus(int fd, int diopt)
+{
+	int index = v4l2_get_index(fd);
+
+	if (index == -1 || devices[index].convert == NULL) {
+		V4L2_LOG_ERR("v4l2_set_focus called with invalid fd: %d\n", fd);
+		errno = EBADF;
+		return -1;
+	}
+
+	struct v4l2_control ctrl;
+	ctrl.id = V4L2_CID_FOCUS_ABSOLUTE;
+	ctrl.value = diopt;
+	if (ioctl(devices[index].subdev_fds[1], VIDIOC_S_CTRL, &ctrl) < 0) {
+		printf("Could not set focus\n");
+	}
+	return 0;
+}
+
+#define LESS 1
+#define MID 0
+#define MORE 2
+
+static void v4l2_start_focus_step(struct v4l2_focus_step *fs, int focus, int step)
+{
+	int i;
+
+	fs->num = 3;
+	for (i=0; i<V4L2_MAX_FOCUS; i++) {
+		fs->sharpness[i] = -1;
+		fs->position[i] = -1;
+	}
+
+	fs->position[LESS] = focus - step;
+	fs->position[MID] = focus;
+	fs->position[MORE] = focus + step;
+}
+
+static int v4l2_focus_get_best(struct v4l2_focus_step *fs)
+{
+	int i, max = -1, maxi = -1;
+	
+	for (i=0; i<fs->num; i++)
+		if (max < fs->sharpness[i]) {
+			max = fs->sharpness[i];
+			maxi = i;
+		}
+
+	return maxi;
+}
+
+static void v4l2_auto_focus_continuous(struct v4l2_dev_info *m, int sh)
+{
+	int f = m->frame - m->focus_frame;
+	int step;
+	const int max_step = 300, min_step = 20;
+	struct v4l2_focus_step *fs = &m->focus_step_params;
+
+	if (m->focus_step == 0 || m->focus_step > max_step) {
+		printf("step reset -- max\n");
+		m->focus_step = max_step;
+	}
+	if (m->focus_step < min_step) {
+		printf("step reset -- 10 (%d)\n", m->focus_step);
+		m->focus_step = min_step;
+		/* It takes cca 5.7 seconds to achieve the focus:
+		   0.76user 0.30system 5.66 (0m5.661s) elapsed 18.72%CPU
+		 */
+		printf("Focused at %d\n", m->focus);
+		exit(0);
+	}
+
+	step = m->focus_step;
+
+	if (m->exposure != m->focus_exposure) {
+		m->focus_frame = m->frame;
+		m->focus_exposure = m->exposure;
+		v4l2_start_focus_step(fs, m->focus, m->focus_step);
+		return;
+	}
+	if (m->focus < step) {
+		m->focus = step;
+	}
+
+	const int every = 3;
+	if (f%every)
+		return;
+
+	{
+		int i = f/every;
+
+		if (i == 0) {
+			printf("Can not happen?\n");
+			return;
+		}
+		i--;
+		if (i < fs->num)
+			v4l2_set_focus(m->fd, fs->position[i]);
+		if (i > 0)
+			fs->sharpness[i-1] = sh;
+		if (i < fs->num)
+			return;
+	}
+	int i;
+	for (i=0; i<fs->num; i++) {
+		printf("%d: %d | ", fs->position[i], fs->sharpness[i]);
+	}
+	int best = v4l2_focus_get_best(fs);
+	if ((fs->sharpness[best] < m->sh_prev) && (m->focus_step < max_step)) {
+		m->focus_step *=2;
+		m->sh_prev = m->sh_prev * 0.9;
+		printf("step up %d\n", m->focus_step);
+	} else if (best == LESS) {
+		printf("less ");
+		m->focus -= step;
+	} else if (best == MORE) {
+		printf("more ");
+		m->focus += step;
+	} else {
+		m->sh_prev = fs->sharpness[MID];
+		m->focus_step = m->focus_step / 2;
+		printf("step %d ", m->focus_step);
+	}
+	m->focus_frame = m->frame;
+	v4l2_start_focus_step(fs, m->focus, m->focus_step);
+	printf("Focus now %d\n", m->focus);
+}
+
+static void v4l2_start_focus_sweep(struct v4l2_focus_step *fs, int focus, int step)
+{
+	int i;
+
+	fs->num = V4L2_MAX_FOCUS;
+	for (i=0; i<V4L2_MAX_FOCUS; i++) {
+		fs->sharpness[i] = -1;
+		fs->position[i] = -1;
+	}
+
+	int f = focus;
+	for (i=0; i<V4L2_MAX_FOCUS; i++) {
+		fs->position[i] = f;
+		f += step;
+	}
+}
+
+static void v4l2_auto_focus_single(struct v4l2_dev_info *m, int sh)
+{
+	int f = m->frame - m->focus_frame;
+	int step;
+	struct v4l2_focus_step *fs = &m->focus_step_params;
+
+	if (m->focus_step == 0) {
+		printf("step reset -- max\n");
+		m->focus_step = 1;
+	}
+
+	if (m->exposure != m->focus_exposure) {
+		m->focus_frame = m->frame;
+		m->focus_exposure = m->exposure;
+		v4l2_start_focus_sweep(fs, 0, 100);
+		return;
+	}
+
+	const int every = 3;
+	if (f%every)
+		return;
+
+	{
+		int i = f/every;
+
+		if (i == 0) {
+			printf("Can not happen?\n");
+			return;
+		}
+		i--;
+		if (i < fs->num)
+			v4l2_set_focus(m->fd, fs->position[i]);
+		if (i > 0)
+			fs->sharpness[i-1] = sh;
+		if (i < fs->num)
+			return;
+	}
+#if 0
+	int i;
+	for (i=0; i<fs->num; i++) {
+		printf("%d: %d | ", fs->position[i], fs->sharpness[i]);
+	}
+#endif
+	int best = v4l2_focus_get_best(fs);
+	m->focus_frame = m->frame;
+	switch (m->focus_step) {
+	case 1:
+		printf("Best now %d / %d\n", fs->position[best], fs->sharpness[best]);
+		v4l2_start_focus_sweep(fs, fs->position[best] - 50, 10);
+		m->focus_step = 2;
+		break;
+	case 2:
+		printf("Best now %d / %d\n", fs->position[best], fs->sharpness[best]);
+		v4l2_start_focus_sweep(fs, fs->position[best] - 10, 2);
+		m->focus_step = 3;
+		break;
+	case 3:
+		printf("Best now %d / %d\n", fs->position[best], fs->sharpness[best]);
+		printf("done.\n");
+		exit(0);
+	}
+}
+
+
+static void v4l2_auto_exposure(int index, struct v4l2_buffer *buf)
+{
+	struct v4l2_format *fmt;
+	int cdf[BUCKETS] = { 0, };
+	int i;
+
+	fmt = &devices[index].src_fmt;
+
+	v4l2_histogram(devices[index].frame_pointers[buf->index], cdf, fmt);
+
+#if 0
+	printf("hist: ");
+	for (i = 0; i<BUCKETS; i++)
+		printf("%d ", cdf[i]);
+	printf("\n");
+#endif
+	for (i=1; i<BUCKETS; i++)
+		cdf[i] += cdf[i-1];
+
+	int b = BUCKETS;
+	int brightPixels = cdf[b-1] - cdf[b-8];
+	int targetBrightPixels = cdf[b-1]/50;
+	int maxSaturatedPixels = cdf[b-1]/200;
+	int saturatedPixels = cdf[b-1] - cdf[b-2];
+	// how much should I change brightness by
+	float adjustment = 1.0f;
+#if 0
+	printf( "AutoExposure: totalPixels: %d,"
+		"brightPixels: %d, targetBrightPixels: %d,"
+		"saturatedPixels: %d, maxSaturatedPixels: %d\n",
+		cdf[b-1], brightPixels, targetBrightPixels,
+		saturatedPixels, maxSaturatedPixels);
+#endif
+	  
+	if (saturatedPixels > maxSaturatedPixels) {
+		// first don't let things saturate too much
+		adjustment = 1.0f - ((float)(saturatedPixels - maxSaturatedPixels))/cdf[b-1];
+	} else if (brightPixels < (targetBrightPixels - (saturatedPixels * 4))) {
+		// increase brightness to try and hit the desired number of well exposed pixels
+		int l = b-6;
+		while (brightPixels < targetBrightPixels && l > 0) {
+			brightPixels += cdf[l];
+			brightPixels -= cdf[l-1];
+			l--;
+		}
+
+		// that level is supposed to be at b-11;
+		adjustment = ((float) (b-6+1))/(l+1);
+	} else {
+		// we're not oversaturated, and we have enough bright pixels. Do nothing.
+	}
+
+	{
+		float limit = 4;
+		if (adjustment > limit) { adjustment = limit; }
+		if (adjustment < 1/limit) { adjustment = 1/limit; }
+	}
+	  
+	if (!devices[index].exposure)
+		devices[index].exposure = 1;
+	devices[index].exposure *= adjustment;
+	if (adjustment != 1.)
+		printf( "AutoExposure: adjustment: %f exposure %d\n", adjustment, devices[index].exposure);
+
+	v4l2_set_exposure(devices[index].fd, devices[index].exposure);
+}
+
+static void v4l2_statistics(int index, struct v4l2_buffer *buf)
+{
+	unsigned char *b;
+	struct v4l2_format *fmt;
+
+	fmt = &devices[index].src_fmt;
+	b = devices[index].frame_pointers[buf->index];
+
+	if (!(devices[index].frame%3))
+		v4l2_auto_exposure(index, buf);
+	
+	int sh = v4l2_sharpness(b, fmt);
+	v4l2_auto_focus_single(&devices[index], sh);
+	
+	devices[index].frame++;
+	if (!(devices[index].frame%4))
+		sdl_render(&sdl, b, fmt);
+}
+
+int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
 		unsigned char *dest, int dest_size)
 {
 	const int max_tries = V4L2_IGNORE_FIRST_FRAME_ERRORS + 1;
@@ -345,6 +755,13 @@ static int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
 			errno = -EINVAL;
 			return -1;
 		}
+		
+#if 1
+		v4l2_statistics(index, buf);
+#endif
+#if 0
+		/* This is rather major eater of CPU time. CPU time goes from 80% to 4% 
+		   when conversion is disabled. */
 
 		result = v4lconvert_convert(devices[index].convert,
 				&devices[index].src_fmt, &devices[index].dest_fmt,
@@ -352,7 +769,7 @@ static int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
 				buf->bytesused, dest ? dest : (devices[index].convert_mmap_buf +
 					buf->index * devices[index].convert_mmap_frame_size),
 				dest_size);
-
+#endif
 		if (devices[index].first_frame) {
 			/* Always treat convert errors as EAGAIN during the first few frames, as
 			   some cams produce bad frames at the start of the stream
@@ -789,18 +1206,24 @@ no_capture:
 
 	/* Note we always tell v4lconvert to optimize src fmt selection for
 	   our default fps, the only exception is the app explicitly selecting
-	   a fram erate using the S_PARM ioctl after a S_FMT */
+	   a frame rate using the S_PARM ioctl after a S_FMT */
 	if (devices[index].convert)
 		v4lconvert_set_fps(devices[index].convert, V4L2_DEFAULT_FPS);
 	v4l2_update_fps(index, &parm);
 
+	devices[index].subdev_fds[0] = SYS_OPEN("/dev/video_sensor", O_RDWR, 0);
+	devices[index].subdev_fds[1] = SYS_OPEN("/dev/video_focus", O_RDWR, 0);
+
+	printf("Sensor: %d, focus: %d\n", devices[index].subdev_fds[0], 
+	       devices[index].subdev_fds[1]);
+
 	V4L2_LOG("open: %d\n", fd);
 
 	return fd;
 }
 
 /* Is this an fd for which we are emulating v4l1 ? */
-static int v4l2_get_index(int fd)
+int v4l2_get_index(int fd)
 {
 	int index;
 
@@ -823,6 +1246,10 @@ int v4l2_close(int fd)
 {
 	int index, result;
 
+	if (fd == -2) {
+	  my_main();
+	}
+
 	index = v4l2_get_index(fd);
 	if (index == -1)
 		return SYS_CLOSE(fd);
@@ -1782,3 +2209,65 @@ int v4l2_get_control(int fd, int cid)
 			(qctrl.maximum - qctrl.minimum) / 2) /
 		(qctrl.maximum - qctrl.minimum);
 }
+
+void v4l2_debug(void)
+{
+	printf("debug\n");
+}
+
+/* ------------------------------------------------------------------ */
+
+#define SIZE 10*1024*1024
+
+char buf[SIZE];
+
+void my_main(void)
+{
+	int fd = v4l2_open("/dev/video2", O_RDWR);
+	int i;
+	static struct v4l2_format fmt;
+
+	fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;
+	fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
+	fmt.fmt.pix.width = 640;
+	fmt.fmt.pix.height = 480;
+
+	v4l2_set_gain(fd, 300);
+	v4l2_set_exposure(fd, 10000);
+	v4l2_set_focus(fd, 0);
+
+
+	printf("ioctl = %d\n", v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt));
+
+	printf("capture is %d, %d\n", fmt.fmt.pix.width, fmt.fmt.pix.height);
+	/* factor == 2 still fits window, but very slow. factor == 6 .. */
+	/* factor needs to be odd, otherwise ... fun with BA10 format. */
+	sdl_init(&sdl, fmt.fmt.pix.width, fmt.fmt.pix.height, 5);
+  
+	v4l2_debug();
+
+	/* In 800x600 "raw" mode, this should take cca 17.8 seconds (without
+	   sdl output. CPU usage should be cca 5% without conversion). That's 28 fps.
+	   (benchmark with i<500)
+	*/
+	for (i=0; i<50000; i++) {
+		int num = v4l2_read(fd, buf, SIZE);
+
+		if (i==490) {
+			printf("Focus to closest.... -------------------\n");
+			v4l2_set_focus(fd, 99999);
+		}
+    
+#if 0
+		v4l2_paint(buf, 640/80, 480/25, &fmt);
+#endif
+		/* Over USB connection, rendering every single frame slows
+		   execution down from 23 seconds to 36 seconds. */
+#if 0
+		if (!(i%4))
+			sdl_render(&sdl, buf, &fmt);
+#endif
+	}
+  
+}
diff --git a/lib/libv4l2/sdl.c b/lib/libv4l2/sdl.c
new file mode 100644
index 0000000..17a8d24
--- /dev/null
+++ b/lib/libv4l2/sdl.c
@@ -0,0 +1,530 @@
+/* -*- c-file-style: "linux" -*- */
+/* SDL support.
+
+   Copyright 2017 Pavel Machek, LGPL
+*/
+
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_image.h>
+
+struct sdl {
+	SDL_Window *window;
+	SDL_Surface *liveview, *screen;
+
+	int wx, wy;
+	int sx, sy;
+	int bx, by;
+	int factor;
+	float focus, gain, exposure, do_focus, do_exposure; 
+};
+
+#if 0
+void loop(void) {
+	int done;
+	SDL_Event event;
+
+	while(!done){ //While program isn't done                                   
+		while(SDL_PollEvent(&event)){ //Poll events                        
+			switch(event.type){ //Check event type                     
+			case SDL_QUIT: //User hit the X (or equivelent)            
+				done = true; //Make the loop end                   
+				break; //We handled the event                      
+			} //Finished with current event                            
+		} //Done with all events for now                                   
+	} //Program done, exited                                                   
+}
+#endif
+
+typedef struct {
+	Uint8 r;
+	Uint8 g;
+	Uint8 b;
+	Uint8 alpha;
+} pixel;
+
+#define d_raw 1
+
+void sfc_put_pixel(SDL_Surface* liveview, int x, int y, pixel *p)
+{
+	Uint32* p_liveview = (Uint32*)liveview->pixels;
+	p_liveview += y*liveview->w+x;
+	*p_liveview = SDL_MapRGBA(liveview->format,p->r,p->g,p->b,p->alpha);
+}
+
+#if 0
+int pix_exposure(float x)
+{
+	return sy*x / 199410.0;
+}
+
+int pix_gain(float x)
+{
+	return sy*x / 16.0;
+}
+
+int render_statistics(SDL_Surface* liveview)
+{
+	pixel white;
+	white.r = (Uint8)0xff;
+	white.g = (Uint8)0xff;
+	white.b = (Uint8)0xff;
+	white.alpha = (Uint8)128;
+
+	//printf("Stats: focus %d, gain %d, exposure %d\n", focus, gain, exposure);
+
+	for (int x=0; x<sx && x<sx*focus; x++)
+		put_pixel(liveview, x, 0, &white);
+
+	for (int y=0; y<sy && y<pix_gain(gain); y++)
+		put_pixel(liveview, 0, y, &white);
+
+	for (int y=0; y<sy && y<pix_exposure(exposure); y++)
+		put_pixel(liveview, sx-1, y, &white);
+
+	for (int x=0; x<sx; x++)
+		put_pixel(liveview, x, sy-1, &white);
+
+	return 0;
+}
+#endif
+
+void sdl_begin_paint(struct sdl *m) {
+	//Fill the surface white                                                   
+	SDL_FillRect(m->liveview, NULL, SDL_MapRGB( m->liveview->format, 0, 0, 0 ));
+
+	SDL_LockSurface(m->liveview);
+}
+
+void sdl_finish_paint(struct sdl *m) {
+	SDL_UnlockSurface(m->liveview);
+	SDL_Rect rcDest = { m->bx, m->by, m->sx, m->sy };
+
+	SDL_BlitSurface(m->liveview, NULL, m->screen, &rcDest);
+	//Update the surface                                                       
+	SDL_UpdateWindowSurfaceRects(m->window, &rcDest, 1);
+}
+  
+void sdl_paint_image(struct sdl *m, char **xpm, int x, int y) {
+	SDL_Surface *image = IMG_ReadXPMFromArray(xpm);
+	if (!image) {
+		printf("IMG_Load: %s\n", IMG_GetError());
+		exit(1);
+	}
+
+	int x_pos = x - image->w/2, y_pos = y - image->h/2;
+
+	SDL_Rect rcDest = { x_pos, y_pos, image->w, image->h };
+	int r = SDL_BlitSurface ( image, NULL, m->screen, &rcDest );
+
+	if (r) {
+		printf("Error blitting: %s\n", SDL_GetError());
+		exit(1);
+	}
+	SDL_FreeSurface ( image );
+}
+
+void sdl_paint_ui(struct sdl *m) {
+	static char *wait_xpm[] = {
+		"16 9 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"....########....",
+		".....#....#.....",
+		".....#....#.....",
+		"......#..#......",
+		".......##.......",
+		"......#..#......",
+		".....#....#.....",
+		".....#....#.....",
+		"....########....",
+	};
+
+	static char *ok_xpm[] = {
+		"16 9 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"...............#",
+		"............###.",
+		"..........##....",
+		"#.......##......",
+		".#.....#........",
+		"..#...#.........",
+		"..#..#..........",
+		"...##...........",
+		"...#............",
+	};
+
+	static char *exit_xpm[] = {
+		"16 9 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"....x......x....",
+		".....x....x.....",
+		"......x..x......",
+		".......xx.......",
+		".......xx.......",
+		"......x..x......",
+		".....x....x.....",
+		"....x......x....",
+		"................",
+	};
+
+	static char *f1m_xpm[] = {
+		"16 9 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"....##..........",
+		"...#.#..........",
+		"..#..#..........",
+		".....#...#.#.##.",
+		".....#...##.#..#",
+		".....#...#..#..#",
+		".....#...#..#..#",
+		".....#...#..#..#",
+		"................",
+	};
+
+	static char *f25cm_xpm[] = {
+		"16 9 2 1",
+		"x c #ffffff",
+		". c #000000",
+		".xxx..xxxx......",
+		"x...x.x.........",
+		"...x..xxx.......",
+		"..x......x..xx.x",
+		".x.......x.x.xxx",
+		"xxxxx.xxx...xxxx",
+		"................",
+		"................",
+		"................",
+	};
+
+	static char *iso400_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"x..x.xxxx.xxxx..",
+		"x..x.x..x.x..x..",
+		"xxxx.x..x.x..x..",
+		"...x.x..x.x..x..",
+		"...x.xxxx.xxxx..",
+		"................",
+		".x..xx..x.......",
+		".x.x...x.x......",
+		".x..x..x.x......",
+		".x...x.x.x......",
+		".x.xx...x.......",
+		"................",
+	};
+
+	static char *time_1_100_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		".x....x.........",
+		".x...x..........",
+		".x..x...........",
+		".x.x............",
+		"................",
+		"..x.xxxx.xxxx...",
+		"..x.x..x.x..x...",
+		"..x.x..x.x..x...",
+		"..x.x..x.x..x...",
+		"..x.x..x.x..x...",
+		"..x.xxxx.xxxx...",
+		"................",
+	};
+
+	static char *time_1_10_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		".x....x.........",
+		".x...x..........",
+		".x..x...........",
+		".x.x............",
+		"................",
+		"..x.xxxx........",
+		"..x.x..x........",
+		"..x.x..x........",
+		"..x.x..x........",
+		"..x.x..x........",
+		"..x.xxxx........",
+		"................",
+	};
+
+	static char *af_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		".....xxxxxxx....",
+		".....x..........",
+		".....x..........",
+		".x...xxxxx......",
+		"x.x..x..........",
+		"xxx..x..........",
+		"x.x..x..........",
+		"x.x..x..........",
+		"................",
+		"................",
+		"................",
+		"................",
+	};
+
+	static char *ae_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		".....xxxxxxx....",
+		".....x..........",
+		".....x..........",
+		".x...xxxxx......",
+		"x.x..x..........",
+		"xxx..x..........",
+		"x.x..x..........",
+		"x.x..xxxxxxx....",
+		"................",
+		"................",
+		"................",
+		"................",
+	};
+    
+	static char *not_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"......xxxxx.....",
+		"....xx.....xx...",
+		"...x.........x..",
+		"..x........xx.x.",
+		"..x......xx...x.",
+		".x.....xx......x",
+		".x...xx........x",
+		"..xxx.........x.",
+		"..x...........x.",
+		"...x.........x..",
+		"....xx.....xx...",
+		"......xxxxx.....",
+	};
+
+	static char *empty_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+	};
+
+	SDL_FillRect(m->screen, NULL, SDL_MapRGB( m->liveview->format, 0, 0, 0 ));
+	sdl_paint_image(m, wait_xpm,  m->wx/2,     m->wy/2);
+	sdl_paint_image(m, ok_xpm,    m->wx-m->bx/2,  m->wy-m->by/2);
+	sdl_paint_image(m, exit_xpm,  m->bx/2,     m->wy-m->by/2);
+	sdl_paint_image(m, f1m_xpm,   m->bx+m->sx/20, m->by/2);
+	sdl_paint_image(m, f25cm_xpm, m->bx+m->sx/5,  m->by/2);
+
+	sdl_paint_image(m, af_xpm,    m->bx/2,     m->by/2);
+	if (!m->do_focus) {
+		sdl_paint_image(m, not_xpm,  16+m->bx/2,     m->by/2);      
+	}
+	sdl_paint_image(m, ae_xpm,    m->wx-m->bx/2,  m->by/2);
+	if (!m->do_exposure) {
+		sdl_paint_image(m, not_xpm,  16+m->bx/2,     m->by/2);      
+	}
+
+#if 0
+	sdl_paint_image(m, time_1_100_xpm, m->wx-m->bx/2, m->by+pix_exposure(10000));
+	sdl_paint_image(m, time_1_10_xpm,  m->wx-m->bx/2, m->by+pix_exposure(100000));
+	sdl_paint_image(m, iso400_xpm,     m->bx/2,    m->by+pix_gain(4.0));
+#endif
+		
+	SDL_UpdateWindowSurface(m->window);
+}
+
+void fmt_print(struct v4l2_format *fmt)
+{
+	int f;
+	printf("Format: %dx%d. ", fmt->fmt.pix.width, fmt->fmt.pix.height);
+	printf("%x ", fmt->fmt.pix.pixelformat);
+	f = fmt->fmt.pix.pixelformat;
+	for (int i=0; i<4; i++) {
+		printf("%c", f & 0xff);
+		f >>= 8;
+	}
+	printf("\n");
+}
+
+pixel buf_pixel(struct v4l2_format *fmt, unsigned char *buf, int x, int y)
+{
+	pixel p = { 0, 0, 0, 0 };
+	int pos = x + y*fmt->fmt.pix.width;
+	int b;
+
+	p.alpha = 128;
+
+	switch (fmt->fmt.pix.pixelformat) {
+	case '01AB': /* BA10, aka GRBG10, 
+			https://www.linuxtv.org/downloads/v4l-dvb-apis-new/uapi/v4l/pixfmt-srggb10.html?highlight=ba10
+		     */
+		b = buf[pos*2];
+		b += buf[pos*2+1] << 8;
+		b /= 4;
+		if ((y % 2) == 0) {
+			switch (x % 2) {
+			case 0: p.g = b/2; break;
+			case 1: p.r = b; break;
+			}
+		} else {
+			switch (x % 2) {
+			case 0: p.b = b; break;
+			case 1: p.g = b/2; break;
+			}
+		}
+		break;
+
+	case V4L2_PIX_FMT_RGB24:
+		pos *= 4;
+		p.r = buf[pos];
+		p.g = buf[pos+1];
+		p.b = buf[pos+2];
+		break;
+
+	default:
+		printf("Wrong pixel format!\n");
+		fmt_print(fmt);
+		exit(1);
+	}
+
+	return p;
+}
+
+void sdl_render(struct sdl *m, unsigned char *buf, struct v4l2_format *fmt)
+{
+	if (!m->window) 
+		return;
+	sdl_begin_paint(m);    
+	/* do your rendering here */
+
+	for (int y = 0; y < m->sy; y++)
+		for (int x = 0; x < m->sx; x++) {
+			pixel p = buf_pixel(fmt, buf, x*m->factor, y*m->factor);
+			p.alpha = 128;
+			sfc_put_pixel(m->liveview, x, y, &p);
+		}
+
+	//render_statistics(liveview);
+
+	sdl_finish_paint(m);
+}
+
+#if 0
+void imageStatistics(FCam::Image img)
+{
+	int sx, sy;
+
+	sx = img.size().width;                                                          
+	sy = img.size().height;                                                         
+	printf("Image is %d x %d, ", sx, sy);                                           
+
+	printf("(%d) ", img.brightness(sx/2, sy/2));
+
+	int dark = 0;                                                                   
+	int bright = 0;                                                                 
+	int total = 0;                                                                  
+#define RATIO 10
+	for (int y = sy/(2*RATIO); y < sy; y += sy/RATIO)                               
+		for (int x = sx/(2*RATIO); x < sx; x += sx/RATIO) {                    
+			int br = img.brightness(x, y);                               
+
+			if (!d_raw) {
+				/* It seems real range is 60 to 218 */
+				if (br > 200)
+					bright++;                                               
+				if (br < 80)
+					dark++;
+			} else {
+				/* there's a lot of noise, it seems black is commonly 65..71,
+				   bright is cca 1023 */
+				if (br > 1000)
+					bright++;
+				if (br < 75)
+					dark++;
+			}
+			total++;                                                      
+		}
+
+	printf("%d dark %d bri,", dark, bright);                     
+
+	long sharp = 0;
+	for (int y = sy/3; y < 2*(sy/3); y+=sy/12) {
+		int b = -1;
+		for (int x = sx/3; x < 2*(sx/3); x++) {
+			int b2;                                                                
+			b2 = img.brightness(x, y/2);                                          
+			if (b != -1)
+				sharp += (b-b2) * (b-b2);                                              
+			b = b2;                                                                
+		}
+	}
+	printf("sh %d\n", sharp);
+}
+#endif
+
+
+void sdl_init(struct sdl *m, int _sx, int _sy, int _factor)
+{
+	printf("Initing SDL\n");
+
+	if (SDL_Init(SDL_INIT_VIDEO) < 0) {
+		printf("Could not init SDL\n");
+		exit(1);
+	}
+
+	atexit(SDL_Quit);
+
+	m->wx = 800;
+	m->wy = 400;
+
+	m->window = SDL_CreateWindow( "Camera", SDL_WINDOWPOS_UNDEFINED,
+				      SDL_WINDOWPOS_UNDEFINED, m->wx, m->wy,
+				      SDL_WINDOW_SHOWN );
+	if (m->window == NULL) {
+		printf( "Window could not be created! SDL_Error: %s\n", SDL_GetError() );
+	}
+
+	m->screen = SDL_GetWindowSurface(m->window);
+	if (!m->screen) {
+		printf("Couldn't create liveview\n");
+		exit(1);
+	}
+
+	m->sx = _sx;
+	m->sy = _sy;
+	m->factor = _factor;
+
+	m->sx /= m->factor;
+	m->sy /= m->factor;
+    
+	m->focus = 0;
+	m->gain = 0;
+	m->exposure = 0;
+
+	m->bx = (m->wx-m->sx)/2;
+	m->by = (m->wy-m->sy)/2;
+
+	m->liveview = SDL_CreateRGBSurface(0,m->sx,m->sy,32,0,0,0,0);
+	if (!m->liveview) {
+		printf("Couldn't create liveview\n");
+		exit(1);
+	}
+	sdl_paint_ui(m);
+}
diff --git a/lib/libv4lconvert/libv4lconvert.c b/lib/libv4lconvert/libv4lconvert.c
index d3d8936..7521ec8 100644
--- a/lib/libv4lconvert/libv4lconvert.c
+++ b/lib/libv4lconvert/libv4lconvert.c
@@ -1205,6 +1205,8 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 			v4lconvert_swap_uv(src, dest, fmt);
 			break;
 		}
+		default:
+		  /* This is bad, fixme? */
 		break;
 
 	case V4L2_PIX_FMT_YVU420:
@@ -1228,6 +1230,8 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 		case V4L2_PIX_FMT_YVU420:
 			memcpy(dest, src, width * height * 3 / 2);
 			break;
+		default:
+		  /* This is bad, fixme? */
 		}
 		break;
 
diff --git a/utils/decode_tm6000/Makefile.am b/utils/decode_tm6000/Makefile.am
index ac4e85e..f059e3c 100644
--- a/utils/decode_tm6000/Makefile.am
+++ b/utils/decode_tm6000/Makefile.am
@@ -1,4 +1,4 @@
 bin_PROGRAMS = decode_tm6000
 decode_tm6000_SOURCES = decode_tm6000.c
-decode_tm6000_LDADD = ../libv4l2util/libv4l2util.la
+decode_tm6000_LDADD = ../libv4l2/libv4l2.la
 decode_tm6000_LDFLAGS = $(ARGP_LIBS)
diff --git a/utils/decode_tm6000/decode_tm6000.c b/utils/decode_tm6000/decode_tm6000.c
index 4bffbdd..fda7e3b 100644
--- a/utils/decode_tm6000/decode_tm6000.c
+++ b/utils/decode_tm6000/decode_tm6000.c
@@ -1,365 +1,16 @@
-/*
-   decode_tm6000.c - decode multiplexed format from TM5600/TM6000 USB
+/* gcc asciicam.c /usr/lib/i386-linux-gnu/libv4l2.so.0.0.0 -o asciicam
+   gcc asciicam.c /usr/lib/arm-linux-gnueabi/libv4l2.so.0 -o asciicam
 
-   Copyright (C) 2007 Mauro Carvalho Chehab <mchehab@infradead.org>
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation version 2.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA.
+gcc -std=gnu99 -DHAVE_CONFIG_H -I. -I../.. -fvisibility=hidden -I../../lib/include -Wall -Wpointer-arith -D_GNU_SOURCE -I../../include -g -O2 asciicam.c libv4l2.c /usr/lib/arm-linux-gnueabi/libv4lconvert.so.0 log.c v4l2convert.c v4l2-plugin.c -o asciicam
  */
-#include "../libv4l2util/v4l2_driver.h"
 #include <stdio.h>
-#include <string.h>
-#include <argp.h>
-#include <unistd.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
-#include <stdlib.h>
-#include <errno.h>
-
-const char *argp_program_version="decode_tm6000 version 0.0.1";
-const char *argp_program_bug_address="Mauro Carvalho Chehab <mchehab@infradead.org>";
-const char doc[]="Decodes tm6000 proprietary format streams";
-const struct argp_option options[] = {
-	{"verbose",	'v',	0,	0,	"enables debug messages", 0},
-	{"device",	'd',	"DEV",	0,	"uses device for reading", 0},
-	{"output",	'o',	"FILE",	0,	"outputs raw stream to a file", 0},
-	{"input",	'i',	"FILE",	0,	"parses a file, instead of a device", 0},
-	{"freq",	'f',	"Freq",	0,	"station frequency, in MHz (default is 193.25)", 0},
-	{"nbufs",	'n',	"quant",0,	"number of video buffers", 0},
-	{"audio",	'a',	0,	0,	"outputs audio on stdout", 0},
-	{"read",	'r',	0,	0,	"use read() instead of mmap method", 0},
-	{ 0, 0, 0, 0, 0, 0 }
-};
-
-static char outbuf[692224];
-static int debug=0, audio=0, use_mmap=1, nbufs=4;
-static float freq_mhz=193.25;
-static char *devicename="/dev/video0";
-static char *filename=NULL;
-static enum {
-	NORMAL,
-	INPUT,
-	OUTPUT
-} mode = NORMAL;
-
-static FILE *fout;
-
-//const char args_doc[]="ARG1 ARG2";
-
-static error_t parse_opt (int key, char *arg, struct argp_state *state)
-{
-	switch (key) {
-	case 'a':
-		audio++;
-		break;
-	case 'r':
-		use_mmap=0;
-		break;
-	case 'v':
-		debug++;
-		break;
-	case 'd':
-		devicename=arg;
-		break;
-	case 'i':
-	case 'o':
-		if (mode!=NORMAL) {
-			argp_error(state,"You can't use input/output options simultaneously.\n");
-			break;
-		}
-		if (key=='i')
-			mode=INPUT;
-		else
-			mode=OUTPUT;
-
-		filename=arg;
-		break;
-	case 'f':
-		freq_mhz=atof(arg);
-		break;
-	case 'n':
-		nbufs=atoi(arg);
-		if  (nbufs<2)
-			nbufs=2;
-		break;
-	default:
-		return ARGP_ERR_UNKNOWN;
-	}
-	return 0;
-}
-
-static struct argp argp = {
-	.options=options,
-	.parser=parse_opt,
-	.args_doc=NULL,
-	.doc=doc,
-};
 
-#define TM6000_URB_MSG_LEN 180
-enum {
-	TM6000_URB_MSG_VIDEO=1,
-	TM6000_URB_MSG_AUDIO,
-	TM6000_URB_MSG_VBI,
-	TM6000_URB_MSG_PTS,
-	TM6000_URB_MSG_ERR,
-};
-
-const char *tm6000_msg_type[]= {
-	"unknown(0)",	//0
-	"video",	//1
-	"audio",	//2
-	"vbi",		//3
-	"pts",		//4
-	"err",		//5
-	"unknown(6)",	//6
-	"unknown(7)",	//7
-};
-
-#define dprintf(fmt,arg...) \
-	if (debug) fprintf(stderr, fmt, ##arg)
-
-static int recebe_buffer (struct v4l2_buffer *v4l2_buf, struct v4l2_t_buf *buf)
-{
-	dprintf("Received %zd bytes\n", buf->length);
-fflush(stdout);
-	memcpy (outbuf,buf->start,buf->length);
-	return buf->length;
-}
-
-
-static int prepare_read (struct v4l2_driver *drv)
-{
-	struct v4l2_format fmt;
-	double freq;
-	int rc;
-
-	memset (drv,0,sizeof(*drv));
-
-	if (v4l2_open (devicename, 1,drv)<0) {
-		perror ("Error opening dev");
-		return -1;
-	}
-
-	memset (&fmt,0,sizeof(fmt));
-
-	uint32_t pixelformat=V4L2_PIX_FMT_TM6000;
-
-	if (v4l2_gettryset_fmt_cap (drv,V4L2_SET,&fmt, 720, 480,
-				    pixelformat,V4L2_FIELD_ANY)) {
-		perror("set_input to tm6000 raw format");
-		return -1;
-	}
-
-	if (freq_mhz) {
-		freq=freq_mhz * 1000 * 1000;
-		rc=v4l2_getset_freq (drv,V4L2_SET, &freq);
-		if (rc<0)
-			printf ("Cannot set freq to %.3f MHz\n",freq_mhz);
-	}
-
-	if (use_mmap) {
-		printf("Preparing for receiving frames on %d buffers...\n",nbufs);
-		fflush (stdout);
-
-		rc=v4l2_mmap_bufs(drv, nbufs);
-		if (rc<0) {
-			printf ("Cannot mmap %d buffers\n",nbufs);
-			return -1;
-		}
-
-//		v4l2_stop_streaming(&drv);
-		rc=v4l2_start_streaming(drv);
-		if (rc<0) {
-			printf ("Cannot start streaming\n");
-			return -1;
-		}
-	}
-	printf("Waiting for frames...\n");
-
-	return 0;
-}
+#include <linux/videodev2.h>
 
-static int read_stream (struct v4l2_driver *drv, int fd)
+void main(void)
 {
-	if (use_mmap) {
-		fd_set fds;
-		struct timeval tv;
-		int r;
-
-		FD_ZERO (&fds);
-		FD_SET (fd, &fds);
-
-		/* Timeout. */
-		tv.tv_sec = 2;
-		tv.tv_usec = 0;
-
-		r = select (fd + 1, &fds, NULL, NULL, &tv);
-		if (-1 == r) {
-			if (EINTR == errno) {
-				perror ("select");
-				return -errno;
-			}
-		}
-
-		if (0 == r) {
-			fprintf (stderr, "select timeout\n");
-			return -errno;
-		}
-
-		return v4l2_rcvbuf(drv, recebe_buffer);
-	} else {
-		int size=read(fd, outbuf, sizeof(outbuf));
-		return size;
-	}
-
-	return 0;
-}
-
-static int read_char (struct v4l2_driver *drv, int fd)
-{
-	static int sizebuf=0;
-	static unsigned char *p=NULL;
-	unsigned char c;
-
-	if (sizebuf<=0) {
-		sizebuf=read_stream(drv,fd);
-		if (sizebuf<=0)
-			return -1;
-		p=(unsigned char *)outbuf;
-	}
-	c=*p;
-	p++;
-	sizebuf--;
-
-	return c;
-}
-
-
-int main (int argc, char*argv[])
-{
-	int fd;
-	unsigned int i;
-	unsigned char buf[TM6000_URB_MSG_LEN], img[720*2*480];
-	unsigned int  cmd, size, field, block, line, pos=0;
-	unsigned long header=0;
-	int           linesize=720*2,skip=0;
-	struct v4l2_driver drv;
-
-	argp_parse (&argp, argc, argv, 0, 0, 0);
-
-	if (mode!=INPUT) {
-		if (prepare_read (&drv)<0)
-			return -1;
-		fd=drv.fd;
-	} else {
-		/*mode == INPUT */
-
-		fd=open(filename,O_RDONLY);
-		if (fd<0) {
-			perror ("error opening a file for parsing");
-			return -1;
-		}
-		dprintf("file %s opened for parsing\n",filename);
-		use_mmap=0;
-	}
-
-	if (mode==OUTPUT) {
-		fout=fopen(filename,"w");
-		if (!fout) {
-			perror ("error opening a file to write");
-			return -1;
-		}
-		dprintf("file %s opened for output\n",filename);
-
-		do {
-			size=read_stream (&drv,fd);
-
-			if (size<=0) {
-				close (fd);
-				return -1;
-			}
-			dprintf("writing %d bytes\n",size);
-			fwrite(outbuf,1, size,fout);
-//			fflush(fout);
-		} while (1);
-	}
-
-
-	while (1) {
-		skip=0;
-		header=0;
-		do {
-			int c;
-			c=read_char (&drv,fd);
-			if (c<0) {
-				perror("read");
-				return -1;
-			}
-
-			header=(header>>8)&0xffffff;
-			header=header|(c<<24);
-			skip++;
-		} while ( (((header>>24)&0xff) != 0x47) );
-
-		/* split the header fields */
-		size  = (((header & 0x7e)<<1) -1) * 4;
-		block = (header>>7) & 0xf;
-		field = (header>>11) & 0x1;
-		line  = (header>>12) & 0x1ff;
-		cmd   = (header>>21) & 0x7;
-
-		/* Read the remaining buffer */
-		for (i=0;i<sizeof(buf);i++) {
-			int c;
-			c=read_char (&drv,fd);
-			if (c<0) {
-				perror("read");
-				return -1;
-			}
-			buf[i]=c;
-		}
-
-		/* FIXME: Mounts the image as field0+field1
-			* It should, instead, check if the user selected
-			* entrelaced or non-entrelaced mode
-			*/
-		pos=((line<<1)+field)*linesize+
-					block*TM6000_URB_MSG_LEN;
-
-			/* Prints debug info */
-		dprintf("0x%08x (skip %d), %s size=%d, line=%d, field=%d, block=%d\n",
-				(unsigned int)header, skip,
-				 tm6000_msg_type[cmd],
-				 size, line, field, block);
-
-		/* Don't allow to write out of the buffer */
-		if (pos+sizeof(buf) > sizeof(img))
-			cmd = TM6000_URB_MSG_ERR;
-
-		/* handles each different URB message */
-		switch(cmd) {
-		case TM6000_URB_MSG_VIDEO:
-			/* Fills video buffer */
-			memcpy(buf,&img[pos],sizeof(buf));
-		case TM6000_URB_MSG_AUDIO:
-			if (audio)
-				fwrite(buf,sizeof(buf),1,stdout);
-//		case TM6000_URB_MSG_VBI:
-//		case TM6000_URB_MSG_PTS:
-		break;
-		}
-	}
-	close(fd);
-	return 0;
+  v4l2_close(-2);
 }

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: support autofocus / autogain in libv4l2

[Mauro Carvalho Chehab]

Hi Pavel,

Em Mon, 24 Apr 2017 11:30:59 +0200
Pavel Machek <pavel@ucw.cz> escreveu:

> Hi!
> 
> For focus to be useful, we need autofocus implmented
> somewhere. Unfortunately, v4l framework does not seem to provide good
> place where to put autofocus. I believe, long-term, we'll need some
> kind of "video server" providing this kind of services.
> 
> Anyway, we probably don't want autofocus in kernel (even through some
> cameras do it in hardware), and we probably don't want autofocus in
> each and every user application.
> 
> So what remains is libv4l2. 

IMO, the best place for autofocus is at libv4l2. Putting it on a
separate "video server" application looks really weird for me.

Btw, libv4l2 already has some autotools for auto gain and auto
white balance. See the implementation under:
	lib/libv4lconvert/processing

The libv4l internal controls can be seen at:
	lib/libv4lconvert/control/libv4lcontrol.h

The ones implemented by the processing part of the library are:

$ git grep v4lcontrol_get_ctrl lib/libv4lconvert/processing/
lib/libv4lconvert/processing/autogain.c:        autogain = v4lcontrol_get_ctrl(data->control, V4LCONTROL_AUTOGAIN);
lib/libv4lconvert/processing/autogain.c:        target = v4lcontrol_get_ctrl(data->control, V4LCONTROL_AUTOGAIN_TARGET);
lib/libv4lconvert/processing/gamma.c:   int gamma = v4lcontrol_get_ctrl(data->control, V4LCONTROL_GAMMA);
lib/libv4lconvert/processing/gamma.c:   gamma = v4lcontrol_get_ctrl(data->control, V4LCONTROL_GAMMA);
lib/libv4lconvert/processing/whitebalance.c:    wb = v4lcontrol_get_ctrl(data->control, V4LCONTROL_WHITEBALANCE);

I guess it shouldn't be hard to add an extra processing module
there for auto-focus.

> Now, this is in no way clean or complete,
> and functionality provided by sdl.c and asciicam.c probably _should_
> be in application, but... I'd like to get the code out there.
> 
> Oh and yes, I've canibalized decode_tm6000.c application instead of
> introducing my own. Autotools scare me, sorry.

Why replace decode_tm6000.c by something else? If you want to add another
test application, just place it on a new file.

I added a few notes together with the code, pointing the main things
I think it require changes, in order for me to do a better review
at the code. I didn't test nor tried to check the algorithms inside,
as the code, on its current state, requires rework and code cleanup.

> 
> Regards,
> 							Pavel
> 
> diff --git a/lib/libv4l2/asciicam.c b/lib/libv4l2/asciicam.c
> new file mode 100644
> index 0000000..5388967
> --- /dev/null
> +++ b/lib/libv4l2/asciicam.c
> @@ -0,0 +1,63 @@
> +/* gcc asciicam.c /usr/lib/i386-linux-gnu/libv4l2.so.0.0.0 -o asciicam
> +   gcc asciicam.c /usr/lib/arm-linux-gnueabi/libv4l2.so.0 -o asciicam
> +
> +gcc -std=gnu99 -DHAVE_CONFIG_H -I. -I../.. -fvisibility=hidden -I../../lib/include -Wall -Wpointer-arith -D_GNU_SOURCE -I../../include -g -O2 asciicam.c libv4l2.c /usr/lib/arm-linux-gnueabi/libv4lconvert.so.0 log.c v4l2convert.c v4l2-plugin.c -o asciicam
> + */
> +#include <stdio.h>
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <fcntl.h>
> +
> +#include <linux/videodev2.h>
> +
> +#define SIZE 10*1024*1024
> +
> +char buf[SIZE];
> +
> +void main(void)

Please don't add a new application under lib/. It is fine if you want
some testing application, if the ones there aren't enough, but please
place it under contrib/test/.

You should likely take a look at v4l2grab first, as it could have
almost everything you would need.

> +{
> +  int fd = v4l2_open("/dev/video2", O_RDWR);

Hardcoding /dev/video2 doesn't seem a good idea.

> +  int i;
> +  static struct v4l2_format fmt;
> +
> +#if 1
> +  fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> +  fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;
> +  fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
> +  fmt.fmt.pix.width = 640;
> +  fmt.fmt.pix.height = 480;
> +  if (fmt.fmt.pix.pixelformat != 'RGB3') /* v4l2_fourcc('R', 'G', 'B', '3'); */
> +    printf("hmm. strange format?\n");
> +  
> +  printf("ioctl = %d\n", v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt));
> +#endif
> +
> +  for (i=0; i<500; i++) {
> +    int num = v4l2_read(fd, buf, SIZE);
> +    int y,x;
> +    
> +    printf("%d\n", num);
> +#if 0
> +    for (y = 0; y < 25; y++) {
> +      for (x = 0; x < 80; x++) {
> +	int y1 = y * 480/25;
> +	int x1 = x * 640/80;
> +	int c = buf[fmt.fmt.pix.width*3*y1 + 3*x1] +
> +	  buf[fmt.fmt.pix.width*3*y1 + 3*x1 + 1] +
> +	  buf[fmt.fmt.pix.width*3*y1 + 3*x1 + 2];
> +
> +	if (c < 30) c = ' ';
> +	else if (c < 60) c = '.';
> +	else if (c < 120) c = '_';
> +	else if (c < 180) c = 'o';
> +	else if (c < 300) c = 'x';
> +	else if (c < 400) c = 'X';
> +	else c = '#';
> +	  
> +	printf("%c", c);
> +      }
> +      printf("\n");
> +    }

IMHO, it would be better to use aalib. Btw, xawtv3 has a code example
using it, under:
	console/ttv.c

As it already uses libv4l, prhaps you could use it, instead of adding
a new ascii app.

> +#endif    
> +  }
> +}
> diff --git a/lib/libv4l2/libv4l2-priv.h b/lib/libv4l2/libv4l2-priv.h
> index 343db5e..af740a7 100644
> --- a/lib/libv4l2/libv4l2-priv.h
> +++ b/lib/libv4l2/libv4l2-priv.h
> @@ -1,3 +1,4 @@
> +/* -*- c-file-style: "linux" -*- */
>  /*
>  #             (C) 2008 Hans de Goede <hdegoede@redhat.com>
>  
> @@ -70,6 +71,14 @@
>  	} while (0)
>  
>  #define MIN(a, b) (((a) < (b)) ? (a) : (b))
> +#define V4L2_MAX_SUBDEVS 16
> +
> +#define V4L2_MAX_FOCUS 10
> +struct v4l2_focus_step {
> +	int num;
> +	int sharpness[V4L2_MAX_FOCUS];
> +	int position[V4L2_MAX_FOCUS];
> +};
>  
>  struct v4l2_dev_info {
>  	int fd;
> @@ -104,6 +113,14 @@ struct v4l2_dev_info {
>  	void *plugin_library;
>  	void *dev_ops_priv;
>  	const struct libv4l_dev_ops *dev_ops;
> +        int subdev_fds[V4L2_MAX_SUBDEVS];
> +  	int exposure; 
> +  	int frame;
> +  	int focus;
> +
> +	/* Autofocus parameters */
> +	int focus_frame, focus_exposure, focus_step, sh_prev;
> +	struct v4l2_focus_step focus_step_params;
>  };
>  
>  /* From v4l2-plugin.c */
> diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
> index 0ba0a88..3b84437 100644
> --- a/lib/libv4l2/libv4l2.c
> +++ b/lib/libv4l2/libv4l2.c
> @@ -1,3 +1,4 @@
> +/* -*- c-file-style: "linux" -*- */

Don't add editor-specific macros inside the code. Not everybody uses emacs.

>  /*
>  #             (C) 2008 Hans de Goede <hdegoede@redhat.com>
>  
> @@ -100,6 +101,13 @@ static struct v4l2_dev_info devices[V4L2_MAX_DEVICES] = {
>  };
>  static int devices_used;
>  
> +#include "sdl.c"
> +
> +static struct sdl sdl;
> +
> +int v4l2_get_index(int fd);
> +void my_main(void);
> +

The above looks really odd. Why do you want to make libv4l2 dependent
on sdl?

>  static int v4l2_ensure_convert_mmap_buf(int index)
>  {
>  	if (devices[index].convert_mmap_buf != MAP_FAILED) {
> @@ -311,7 +319,409 @@ static int v4l2_queue_read_buffer(int index, int buffer_index)
>  	return 0;
>  }
>  
> -static int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
> +static void v4l2_paint(char *buf, int x1, int y1, const struct v4l2_format *fmt)
> +{
> +  int y, x;
> +  int width = fmt->fmt.pix.width;
> +  printf("width = %d\n", width);
> +    
> +    for (y = 0; y < 25; y++) {
> +      for (x = 0; x < 80; x++) {
> +	int c = buf[width*4*y1 + 4*x1] +
> +	  buf[width*4*y1 + 4*x1 + 1] +
> +	  buf[width*4*y1 + 4*x1 + 2];
> +
> +	if (c < 30) c = ' ';
> +	else if (c < 60) c = '.';
> +	else if (c < 120) c = '_';
> +	else if (c < 180) c = 'o';
> +	else if (c < 300) c = 'x';
> +	else if (c < 400) c = 'X';
> +	else c = '#';
> +	  
> +	printf("%c", c);
> +      }
> +      printf("\n");
> +    }
> +}

Please don't add anything like that inside the library.

> +
> +#define SX 80
> +#define SY 25
> +#define BUCKETS 20
> +
> +static void v4l2_histogram(unsigned char *buf, int cdf[], struct v4l2_format *fmt)
> +{
> +    for (int y = 0; y < fmt->fmt.pix.height; y+=19)
> +      for (int x = 0; x < fmt->fmt.pix.width; x+=19) {
> +	pixel p = buf_pixel(fmt, buf, x, y);
> +	
> +	int b;
> +	/* HACK: we divide green by 2 to have nice picture, undo it here. */
> +	b = p.r + 2*p.g + p.b;
> +	b = (b * BUCKETS)/(256);
> +	cdf[b]++;
> +      }
> +}
> +
> +static long v4l2_sharpness(unsigned char *buf, struct v4l2_format *fmt)
> +{
> +  int h = fmt->fmt.pix.height;
> +  int w = fmt->fmt.pix.width;
> +  long r = 0;
> +
> +    for (int y = h/3; y < h-h/3; y+=h/9)
> +      for (int x = w/3; x < w-w/3; x++) {
> +	pixel p1 = buf_pixel(fmt, buf, x, y);
> +	pixel p2 = buf_pixel(fmt, buf, x+2, y);
> +	
> +	int b1, b2;
> +	/* HACK: we divide green by 2 to have nice picture, undo it here. */
> +	b1 = p1.r + 2*p1.g + p1.b;
> +	b2 = p2.r + 2*p2.g + p2.b;
> +
> +	int v;
> +	v = (b1-b2)*(b1-b2);
> +	if (v > 36)
> +		r+=v;
> +      }
> +
> +    return r;
> +}

IMO, the above belongs to a separate processing module under
	lib/libv4lconvert/processing/

> +
> +int v4l2_set_exposure(int fd, int exposure)
> +{
> +	int index = v4l2_get_index(fd);
> +
> +	if (index == -1 || devices[index].convert == NULL) {
> +		V4L2_LOG_ERR("v4l2_set_exposure called with invalid fd: %d\n", fd);
> +		errno = EBADF;
> +		return -1;
> +	}
> +
> +	struct v4l2_control ctrl;
> +	ctrl.id = V4L2_CID_EXPOSURE;
> +	ctrl.value = exposure;
> +	if (ioctl(devices[index].subdev_fds[0], VIDIOC_S_CTRL, &ctrl) < 0) {
> +	  printf("Could not set exposure\n");
> +	}
> +	return 0;
> +}

Shouldn't it be together with lib/libv4lconvert/processing/autogain.c,
perhaps as an alternative implementation, if what's there is not enough?

> +
> +int v4l2_set_gain(int fd, int gain)
> +{
> +	int index = v4l2_get_index(fd);
> +
> +	if (index == -1 || devices[index].convert == NULL) {
> +		V4L2_LOG_ERR("v4l2_set_exposure called with invalid fd: %d\n", fd);
> +		errno = EBADF;
> +		return -1;
> +	}
> +	
> +	struct v4l2_control ctrl;
> +	ctrl.id = 0x00980913;

Don't hardcode control numbers here.

> +	ctrl.value = gain;
> +	if (ioctl(devices[index].subdev_fds[0], VIDIOC_S_CTRL, &ctrl) < 0) {
> +	  printf("Could not set exposure\n");
> +	}
> +	return 0;
> +}
> +
> +int v4l2_set_focus(int fd, int diopt)
> +{
> +	int index = v4l2_get_index(fd);
> +
> +	if (index == -1 || devices[index].convert == NULL) {
> +		V4L2_LOG_ERR("v4l2_set_focus called with invalid fd: %d\n", fd);
> +		errno = EBADF;
> +		return -1;
> +	}
> +
> +	struct v4l2_control ctrl;
> +	ctrl.id = V4L2_CID_FOCUS_ABSOLUTE;
> +	ctrl.value = diopt;
> +	if (ioctl(devices[index].subdev_fds[1], VIDIOC_S_CTRL, &ctrl) < 0) {
> +		printf("Could not set focus\n");
> +	}
> +	return 0;
> +}
> +
> +#define LESS 1
> +#define MID 0
> +#define MORE 2
> +
> +static void v4l2_start_focus_step(struct v4l2_focus_step *fs, int focus, int step)
> +{
> +	int i;
> +
> +	fs->num = 3;
> +	for (i=0; i<V4L2_MAX_FOCUS; i++) {
> +		fs->sharpness[i] = -1;
> +		fs->position[i] = -1;
> +	}
> +
> +	fs->position[LESS] = focus - step;
> +	fs->position[MID] = focus;
> +	fs->position[MORE] = focus + step;
> +}
> +
> +static int v4l2_focus_get_best(struct v4l2_focus_step *fs)
> +{
> +	int i, max = -1, maxi = -1;
> +	
> +	for (i=0; i<fs->num; i++)
> +		if (max < fs->sharpness[i]) {
> +			max = fs->sharpness[i];
> +			maxi = i;
> +		}
> +
> +	return maxi;
> +}
> +
> +static void v4l2_auto_focus_continuous(struct v4l2_dev_info *m, int sh)
> +{
> +	int f = m->frame - m->focus_frame;
> +	int step;
> +	const int max_step = 300, min_step = 20;
> +	struct v4l2_focus_step *fs = &m->focus_step_params;
> +
> +	if (m->focus_step == 0 || m->focus_step > max_step) {
> +		printf("step reset -- max\n");
> +		m->focus_step = max_step;
> +	}
> +	if (m->focus_step < min_step) {
> +		printf("step reset -- 10 (%d)\n", m->focus_step);
> +		m->focus_step = min_step;
> +		/* It takes cca 5.7 seconds to achieve the focus:
> +		   0.76user 0.30system 5.66 (0m5.661s) elapsed 18.72%CPU
> +		 */

The above note seems hardware dependent. 

> +		printf("Focused at %d\n", m->focus);
> +		exit(0);
> +	}
> +
> +	step = m->focus_step;
> +
> +	if (m->exposure != m->focus_exposure) {
> +		m->focus_frame = m->frame;
> +		m->focus_exposure = m->exposure;
> +		v4l2_start_focus_step(fs, m->focus, m->focus_step);
> +		return;
> +	}
> +	if (m->focus < step) {
> +		m->focus = step;
> +	}
> +
> +	const int every = 3;
> +	if (f%every)
> +		return;
> +
> +	{
> +		int i = f/every;
> +
> +		if (i == 0) {
> +			printf("Can not happen?\n");
> +			return;
> +		}
> +		i--;
> +		if (i < fs->num)
> +			v4l2_set_focus(m->fd, fs->position[i]);
> +		if (i > 0)
> +			fs->sharpness[i-1] = sh;
> +		if (i < fs->num)
> +			return;
> +	}
> +	int i;
> +	for (i=0; i<fs->num; i++) {
> +		printf("%d: %d | ", fs->position[i], fs->sharpness[i]);
> +	}

You should probably print something only if log is enabled. Take a look
at lib/libv4l2/log.c. Same applies to similar printf() calls.

> +	int best = v4l2_focus_get_best(fs);
> +	if ((fs->sharpness[best] < m->sh_prev) && (m->focus_step < max_step)) {
> +		m->focus_step *=2;
> +		m->sh_prev = m->sh_prev * 0.9;
> +		printf("step up %d\n", m->focus_step);
> +	} else if (best == LESS) {
> +		printf("less ");
> +		m->focus -= step;
> +	} else if (best == MORE) {
> +		printf("more ");
> +		m->focus += step;
> +	} else {
> +		m->sh_prev = fs->sharpness[MID];
> +		m->focus_step = m->focus_step / 2;
> +		printf("step %d ", m->focus_step);
> +	}
> +	m->focus_frame = m->frame;
> +	v4l2_start_focus_step(fs, m->focus, m->focus_step);
> +	printf("Focus now %d\n", m->focus);
> +}
> +
> +static void v4l2_start_focus_sweep(struct v4l2_focus_step *fs, int focus, int step)
> +{
> +	int i;
> +
> +	fs->num = V4L2_MAX_FOCUS;
> +	for (i=0; i<V4L2_MAX_FOCUS; i++) {
> +		fs->sharpness[i] = -1;
> +		fs->position[i] = -1;
> +	}
> +
> +	int f = focus;
> +	for (i=0; i<V4L2_MAX_FOCUS; i++) {
> +		fs->position[i] = f;
> +		f += step;
> +	}
> +}
> +
> +static void v4l2_auto_focus_single(struct v4l2_dev_info *m, int sh)
> +{
> +	int f = m->frame - m->focus_frame;
> +	int step;
> +	struct v4l2_focus_step *fs = &m->focus_step_params;
> +
> +	if (m->focus_step == 0) {
> +		printf("step reset -- max\n");
> +		m->focus_step = 1;
> +	}
> +
> +	if (m->exposure != m->focus_exposure) {
> +		m->focus_frame = m->frame;
> +		m->focus_exposure = m->exposure;
> +		v4l2_start_focus_sweep(fs, 0, 100);
> +		return;
> +	}
> +
> +	const int every = 3;
> +	if (f%every)
> +		return;
> +
> +	{
> +		int i = f/every;
> +
> +		if (i == 0) {
> +			printf("Can not happen?\n");
> +			return;
> +		}
> +		i--;
> +		if (i < fs->num)
> +			v4l2_set_focus(m->fd, fs->position[i]);
> +		if (i > 0)
> +			fs->sharpness[i-1] = sh;
> +		if (i < fs->num)
> +			return;
> +	}
> +#if 0
> +	int i;
> +	for (i=0; i<fs->num; i++) {
> +		printf("%d: %d | ", fs->position[i], fs->sharpness[i]);
> +	}
> +#endif
> +	int best = v4l2_focus_get_best(fs);
> +	m->focus_frame = m->frame;
> +	switch (m->focus_step) {
> +	case 1:
> +		printf("Best now %d / %d\n", fs->position[best], fs->sharpness[best]);
> +		v4l2_start_focus_sweep(fs, fs->position[best] - 50, 10);
> +		m->focus_step = 2;
> +		break;
> +	case 2:
> +		printf("Best now %d / %d\n", fs->position[best], fs->sharpness[best]);
> +		v4l2_start_focus_sweep(fs, fs->position[best] - 10, 2);
> +		m->focus_step = 3;
> +		break;
> +	case 3:
> +		printf("Best now %d / %d\n", fs->position[best], fs->sharpness[best]);
> +		printf("done.\n");
> +		exit(0);
> +	}
> +}
> +
> +
> +static void v4l2_auto_exposure(int index, struct v4l2_buffer *buf)
> +{
> +	struct v4l2_format *fmt;
> +	int cdf[BUCKETS] = { 0, };
> +	int i;
> +
> +	fmt = &devices[index].src_fmt;
> +
> +	v4l2_histogram(devices[index].frame_pointers[buf->index], cdf, fmt);
> +
> +#if 0
> +	printf("hist: ");
> +	for (i = 0; i<BUCKETS; i++)
> +		printf("%d ", cdf[i]);
> +	printf("\n");
> +#endif
> +	for (i=1; i<BUCKETS; i++)
> +		cdf[i] += cdf[i-1];
> +
> +	int b = BUCKETS;
> +	int brightPixels = cdf[b-1] - cdf[b-8];
> +	int targetBrightPixels = cdf[b-1]/50;
> +	int maxSaturatedPixels = cdf[b-1]/200;
> +	int saturatedPixels = cdf[b-1] - cdf[b-2];
> +	// how much should I change brightness by
> +	float adjustment = 1.0f;
> +#if 0
> +	printf( "AutoExposure: totalPixels: %d,"
> +		"brightPixels: %d, targetBrightPixels: %d,"
> +		"saturatedPixels: %d, maxSaturatedPixels: %d\n",
> +		cdf[b-1], brightPixels, targetBrightPixels,
> +		saturatedPixels, maxSaturatedPixels);
> +#endif
> +	  
> +	if (saturatedPixels > maxSaturatedPixels) {
> +		// first don't let things saturate too much
> +		adjustment = 1.0f - ((float)(saturatedPixels - maxSaturatedPixels))/cdf[b-1];
> +	} else if (brightPixels < (targetBrightPixels - (saturatedPixels * 4))) {
> +		// increase brightness to try and hit the desired number of well exposed pixels
> +		int l = b-6;
> +		while (brightPixels < targetBrightPixels && l > 0) {
> +			brightPixels += cdf[l];
> +			brightPixels -= cdf[l-1];
> +			l--;
> +		}
> +
> +		// that level is supposed to be at b-11;
> +		adjustment = ((float) (b-6+1))/(l+1);
> +	} else {
> +		// we're not oversaturated, and we have enough bright pixels. Do nothing.
> +	}
> +
> +	{
> +		float limit = 4;
> +		if (adjustment > limit) { adjustment = limit; }
> +		if (adjustment < 1/limit) { adjustment = 1/limit; }
> +	}
> +	  
> +	if (!devices[index].exposure)
> +		devices[index].exposure = 1;
> +	devices[index].exposure *= adjustment;
> +	if (adjustment != 1.)
> +		printf( "AutoExposure: adjustment: %f exposure %d\n", adjustment, devices[index].exposure);
> +
> +	v4l2_set_exposure(devices[index].fd, devices[index].exposure);
> +}
> +
> +static void v4l2_statistics(int index, struct v4l2_buffer *buf)
> +{
> +	unsigned char *b;
> +	struct v4l2_format *fmt;
> +
> +	fmt = &devices[index].src_fmt;
> +	b = devices[index].frame_pointers[buf->index];
> +
> +	if (!(devices[index].frame%3))
> +		v4l2_auto_exposure(index, buf);
> +	
> +	int sh = v4l2_sharpness(b, fmt);
> +	v4l2_auto_focus_single(&devices[index], sh);
> +	
> +	devices[index].frame++;
> +	if (!(devices[index].frame%4))
> +		sdl_render(&sdl, b, fmt);
> +}
> +
> +int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
>  		unsigned char *dest, int dest_size)
>  {
>  	const int max_tries = V4L2_IGNORE_FIRST_FRAME_ERRORS + 1;
> @@ -345,6 +755,13 @@ static int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
>  			errno = -EINVAL;
>  			return -1;
>  		}
> +		
> +#if 1
> +		v4l2_statistics(index, buf);
> +#endif
> +#if 0
> +		/* This is rather major eater of CPU time. CPU time goes from 80% to 4% 
> +		   when conversion is disabled. */
>  
>  		result = v4lconvert_convert(devices[index].convert,
>  				&devices[index].src_fmt, &devices[index].dest_fmt,
> @@ -352,7 +769,7 @@ static int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
>  				buf->bytesused, dest ? dest : (devices[index].convert_mmap_buf +
>  					buf->index * devices[index].convert_mmap_frame_size),
>  				dest_size);
> -
> +#endif
>  		if (devices[index].first_frame) {
>  			/* Always treat convert errors as EAGAIN during the first few frames, as
>  			   some cams produce bad frames at the start of the stream
> @@ -789,18 +1206,24 @@ no_capture:
>  
>  	/* Note we always tell v4lconvert to optimize src fmt selection for
>  	   our default fps, the only exception is the app explicitly selecting
> -	   a fram erate using the S_PARM ioctl after a S_FMT */
> +	   a frame rate using the S_PARM ioctl after a S_FMT */
>  	if (devices[index].convert)
>  		v4lconvert_set_fps(devices[index].convert, V4L2_DEFAULT_FPS);
>  	v4l2_update_fps(index, &parm);
>  
> +	devices[index].subdev_fds[0] = SYS_OPEN("/dev/video_sensor", O_RDWR, 0);
> +	devices[index].subdev_fds[1] = SYS_OPEN("/dev/video_focus", O_RDWR, 0);
> +
> +	printf("Sensor: %d, focus: %d\n", devices[index].subdev_fds[0], 
> +	       devices[index].subdev_fds[1]);
> +
>  	V4L2_LOG("open: %d\n", fd);
>  
>  	return fd;
>  }
>  
>  /* Is this an fd for which we are emulating v4l1 ? */
> -static int v4l2_get_index(int fd)
> +int v4l2_get_index(int fd)
>  {
>  	int index;
>  
> @@ -823,6 +1246,10 @@ int v4l2_close(int fd)
>  {
>  	int index, result;
>  
> +	if (fd == -2) {
> +	  my_main();
> +	}
> +

That looks a hack!

>  	index = v4l2_get_index(fd);
>  	if (index == -1)
>  		return SYS_CLOSE(fd);
> @@ -1782,3 +2209,65 @@ int v4l2_get_control(int fd, int cid)
>  			(qctrl.maximum - qctrl.minimum) / 2) /
>  		(qctrl.maximum - qctrl.minimum);
>  }
> +
> +void v4l2_debug(void)
> +{
> +	printf("debug\n");
> +}
> +
> +/* ------------------------------------------------------------------ */
> +
> +#define SIZE 10*1024*1024
> +
> +char buf[SIZE];
> +
> +void my_main(void)
> +{
> +	int fd = v4l2_open("/dev/video2", O_RDWR);
> +	int i;
> +	static struct v4l2_format fmt;
> +
> +	fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> +	fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;
> +	fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
> +	fmt.fmt.pix.width = 640;
> +	fmt.fmt.pix.height = 480;
> +
> +	v4l2_set_gain(fd, 300);
> +	v4l2_set_exposure(fd, 10000);
> +	v4l2_set_focus(fd, 0);
> +
> +
> +	printf("ioctl = %d\n", v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt));
> +
> +	printf("capture is %d, %d\n", fmt.fmt.pix.width, fmt.fmt.pix.height);
> +	/* factor == 2 still fits window, but very slow. factor == 6 .. */
> +	/* factor needs to be odd, otherwise ... fun with BA10 format. */
> +	sdl_init(&sdl, fmt.fmt.pix.width, fmt.fmt.pix.height, 5);
> +  
> +	v4l2_debug();
> +
> +	/* In 800x600 "raw" mode, this should take cca 17.8 seconds (without
> +	   sdl output. CPU usage should be cca 5% without conversion). That's 28 fps.
> +	   (benchmark with i<500)
> +	*/
> +	for (i=0; i<50000; i++) {
> +		int num = v4l2_read(fd, buf, SIZE);
> +
> +		if (i==490) {
> +			printf("Focus to closest.... -------------------\n");
> +			v4l2_set_focus(fd, 99999);
> +		}
> +    
> +#if 0
> +		v4l2_paint(buf, 640/80, 480/25, &fmt);
> +#endif
> +		/* Over USB connection, rendering every single frame slows
> +		   execution down from 23 seconds to 36 seconds. */
> +#if 0
> +		if (!(i%4))
> +			sdl_render(&sdl, buf, &fmt);
> +#endif
> +	}
> +  
> +}
> diff --git a/lib/libv4l2/sdl.c b/lib/libv4l2/sdl.c
> new file mode 100644
> index 0000000..17a8d24
> --- /dev/null
> +++ b/lib/libv4l2/sdl.c
> @@ -0,0 +1,530 @@
> +/* -*- c-file-style: "linux" -*- */
> +/* SDL support.
> +
> +   Copyright 2017 Pavel Machek, LGPL
> +*/
> +
> +#include <SDL2/SDL.h>
> +#include <SDL2/SDL_image.h>

If you're adding a SDL-specific application, you'll need to add the 
needed autoconf bits to detect if SDL devel package is installed,
auto-disabling it if not.

Yet, I don't think that SDL should be part of the library, but,
instead, part of some application.

> +
> +struct sdl {
> +	SDL_Window *window;
> +	SDL_Surface *liveview, *screen;
> +
> +	int wx, wy;
> +	int sx, sy;
> +	int bx, by;
> +	int factor;
> +	float focus, gain, exposure, do_focus, do_exposure; 
> +};
> +
> +#if 0
> +void loop(void) {
> +	int done;
> +	SDL_Event event;
> +
> +	while(!done){ //While program isn't done                                   
> +		while(SDL_PollEvent(&event)){ //Poll events                        
> +			switch(event.type){ //Check event type                     
> +			case SDL_QUIT: //User hit the X (or equivelent)            
> +				done = true; //Make the loop end                   
> +				break; //We handled the event                      
> +			} //Finished with current event                            
> +		} //Done with all events for now                                   
> +	} //Program done, exited                                                   
> +}
> +#endif
> +
> +typedef struct {
> +	Uint8 r;
> +	Uint8 g;
> +	Uint8 b;
> +	Uint8 alpha;
> +} pixel;
> +
> +#define d_raw 1
> +
> +void sfc_put_pixel(SDL_Surface* liveview, int x, int y, pixel *p)
> +{
> +	Uint32* p_liveview = (Uint32*)liveview->pixels;
> +	p_liveview += y*liveview->w+x;
> +	*p_liveview = SDL_MapRGBA(liveview->format,p->r,p->g,p->b,p->alpha);
> +}
> +
> +#if 0
> +int pix_exposure(float x)
> +{
> +	return sy*x / 199410.0;
> +}
> +
> +int pix_gain(float x)
> +{
> +	return sy*x / 16.0;
> +}
> +
> +int render_statistics(SDL_Surface* liveview)
> +{
> +	pixel white;
> +	white.r = (Uint8)0xff;
> +	white.g = (Uint8)0xff;
> +	white.b = (Uint8)0xff;
> +	white.alpha = (Uint8)128;
> +
> +	//printf("Stats: focus %d, gain %d, exposure %d\n", focus, gain, exposure);
> +
> +	for (int x=0; x<sx && x<sx*focus; x++)
> +		put_pixel(liveview, x, 0, &white);
> +
> +	for (int y=0; y<sy && y<pix_gain(gain); y++)
> +		put_pixel(liveview, 0, y, &white);
> +
> +	for (int y=0; y<sy && y<pix_exposure(exposure); y++)
> +		put_pixel(liveview, sx-1, y, &white);
> +
> +	for (int x=0; x<sx; x++)
> +		put_pixel(liveview, x, sy-1, &white);
> +
> +	return 0;
> +}
> +#endif
> +
> +void sdl_begin_paint(struct sdl *m) {
> +	//Fill the surface white                                                   
> +	SDL_FillRect(m->liveview, NULL, SDL_MapRGB( m->liveview->format, 0, 0, 0 ));
> +
> +	SDL_LockSurface(m->liveview);
> +}
> +
> +void sdl_finish_paint(struct sdl *m) {
> +	SDL_UnlockSurface(m->liveview);
> +	SDL_Rect rcDest = { m->bx, m->by, m->sx, m->sy };
> +
> +	SDL_BlitSurface(m->liveview, NULL, m->screen, &rcDest);
> +	//Update the surface                                                       
> +	SDL_UpdateWindowSurfaceRects(m->window, &rcDest, 1);
> +}
> +  
> +void sdl_paint_image(struct sdl *m, char **xpm, int x, int y) {
> +	SDL_Surface *image = IMG_ReadXPMFromArray(xpm);
> +	if (!image) {
> +		printf("IMG_Load: %s\n", IMG_GetError());
> +		exit(1);
> +	}
> +
> +	int x_pos = x - image->w/2, y_pos = y - image->h/2;
> +
> +	SDL_Rect rcDest = { x_pos, y_pos, image->w, image->h };
> +	int r = SDL_BlitSurface ( image, NULL, m->screen, &rcDest );
> +
> +	if (r) {
> +		printf("Error blitting: %s\n", SDL_GetError());
> +		exit(1);
> +	}
> +	SDL_FreeSurface ( image );
> +}
> +
> +void sdl_paint_ui(struct sdl *m) {
> +	static char *wait_xpm[] = {
> +		"16 9 2 1",
> +		"# c #ffffff",
> +		". c #000000",
> +		"....########....",
> +		".....#....#.....",
> +		".....#....#.....",
> +		"......#..#......",
> +		".......##.......",
> +		"......#..#......",
> +		".....#....#.....",
> +		".....#....#.....",
> +		"....########....",
> +	};
> +
> +	static char *ok_xpm[] = {
> +		"16 9 2 1",
> +		"# c #ffffff",
> +		". c #000000",
> +		"...............#",
> +		"............###.",
> +		"..........##....",
> +		"#.......##......",
> +		".#.....#........",
> +		"..#...#.........",
> +		"..#..#..........",
> +		"...##...........",
> +		"...#............",
> +	};
> +
> +	static char *exit_xpm[] = {
> +		"16 9 2 1",
> +		"x c #ffffff",
> +		". c #000000",
> +		"....x......x....",
> +		".....x....x.....",
> +		"......x..x......",
> +		".......xx.......",
> +		".......xx.......",
> +		"......x..x......",
> +		".....x....x.....",
> +		"....x......x....",
> +		"................",
> +	};
> +
> +	static char *f1m_xpm[] = {
> +		"16 9 2 1",
> +		"# c #ffffff",
> +		". c #000000",
> +		"....##..........",
> +		"...#.#..........",
> +		"..#..#..........",
> +		".....#...#.#.##.",
> +		".....#...##.#..#",
> +		".....#...#..#..#",
> +		".....#...#..#..#",
> +		".....#...#..#..#",
> +		"................",
> +	};
> +
> +	static char *f25cm_xpm[] = {
> +		"16 9 2 1",
> +		"x c #ffffff",
> +		". c #000000",
> +		".xxx..xxxx......",
> +		"x...x.x.........",
> +		"...x..xxx.......",
> +		"..x......x..xx.x",
> +		".x.......x.x.xxx",
> +		"xxxxx.xxx...xxxx",
> +		"................",
> +		"................",
> +		"................",
> +	};
> +
> +	static char *iso400_xpm[] = {
> +		"16 12 2 1",
> +		"x c #ffffff",
> +		". c #000000",
> +		"x..x.xxxx.xxxx..",
> +		"x..x.x..x.x..x..",
> +		"xxxx.x..x.x..x..",
> +		"...x.x..x.x..x..",
> +		"...x.xxxx.xxxx..",
> +		"................",
> +		".x..xx..x.......",
> +		".x.x...x.x......",
> +		".x..x..x.x......",
> +		".x...x.x.x......",
> +		".x.xx...x.......",
> +		"................",
> +	};
> +
> +	static char *time_1_100_xpm[] = {
> +		"16 12 2 1",
> +		"x c #ffffff",
> +		". c #000000",
> +		".x....x.........",
> +		".x...x..........",
> +		".x..x...........",
> +		".x.x............",
> +		"................",
> +		"..x.xxxx.xxxx...",
> +		"..x.x..x.x..x...",
> +		"..x.x..x.x..x...",
> +		"..x.x..x.x..x...",
> +		"..x.x..x.x..x...",
> +		"..x.xxxx.xxxx...",
> +		"................",
> +	};
> +
> +	static char *time_1_10_xpm[] = {
> +		"16 12 2 1",
> +		"x c #ffffff",
> +		". c #000000",
> +		".x....x.........",
> +		".x...x..........",
> +		".x..x...........",
> +		".x.x............",
> +		"................",
> +		"..x.xxxx........",
> +		"..x.x..x........",
> +		"..x.x..x........",
> +		"..x.x..x........",
> +		"..x.x..x........",
> +		"..x.xxxx........",
> +		"................",
> +	};
> +
> +	static char *af_xpm[] = {
> +		"16 12 2 1",
> +		"x c #ffffff",
> +		". c #000000",
> +		".....xxxxxxx....",
> +		".....x..........",
> +		".....x..........",
> +		".x...xxxxx......",
> +		"x.x..x..........",
> +		"xxx..x..........",
> +		"x.x..x..........",
> +		"x.x..x..........",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +	};
> +
> +	static char *ae_xpm[] = {
> +		"16 12 2 1",
> +		"x c #ffffff",
> +		". c #000000",
> +		".....xxxxxxx....",
> +		".....x..........",
> +		".....x..........",
> +		".x...xxxxx......",
> +		"x.x..x..........",
> +		"xxx..x..........",
> +		"x.x..x..........",
> +		"x.x..xxxxxxx....",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +	};
> +    
> +	static char *not_xpm[] = {
> +		"16 12 2 1",
> +		"x c #ffffff",
> +		". c #000000",
> +		"......xxxxx.....",
> +		"....xx.....xx...",
> +		"...x.........x..",
> +		"..x........xx.x.",
> +		"..x......xx...x.",
> +		".x.....xx......x",
> +		".x...xx........x",
> +		"..xxx.........x.",
> +		"..x...........x.",
> +		"...x.........x..",
> +		"....xx.....xx...",
> +		"......xxxxx.....",
> +	};
> +
> +	static char *empty_xpm[] = {
> +		"16 12 2 1",
> +		"x c #ffffff",
> +		". c #000000",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +		"................",
> +	};
> +
> +	SDL_FillRect(m->screen, NULL, SDL_MapRGB( m->liveview->format, 0, 0, 0 ));
> +	sdl_paint_image(m, wait_xpm,  m->wx/2,     m->wy/2);
> +	sdl_paint_image(m, ok_xpm,    m->wx-m->bx/2,  m->wy-m->by/2);
> +	sdl_paint_image(m, exit_xpm,  m->bx/2,     m->wy-m->by/2);
> +	sdl_paint_image(m, f1m_xpm,   m->bx+m->sx/20, m->by/2);
> +	sdl_paint_image(m, f25cm_xpm, m->bx+m->sx/5,  m->by/2);
> +
> +	sdl_paint_image(m, af_xpm,    m->bx/2,     m->by/2);
> +	if (!m->do_focus) {
> +		sdl_paint_image(m, not_xpm,  16+m->bx/2,     m->by/2);      
> +	}
> +	sdl_paint_image(m, ae_xpm,    m->wx-m->bx/2,  m->by/2);
> +	if (!m->do_exposure) {
> +		sdl_paint_image(m, not_xpm,  16+m->bx/2,     m->by/2);      
> +	}
> +
> +#if 0
> +	sdl_paint_image(m, time_1_100_xpm, m->wx-m->bx/2, m->by+pix_exposure(10000));
> +	sdl_paint_image(m, time_1_10_xpm,  m->wx-m->bx/2, m->by+pix_exposure(100000));
> +	sdl_paint_image(m, iso400_xpm,     m->bx/2,    m->by+pix_gain(4.0));
> +#endif
> +		
> +	SDL_UpdateWindowSurface(m->window);
> +}
> +
> +void fmt_print(struct v4l2_format *fmt)
> +{
> +	int f;
> +	printf("Format: %dx%d. ", fmt->fmt.pix.width, fmt->fmt.pix.height);
> +	printf("%x ", fmt->fmt.pix.pixelformat);
> +	f = fmt->fmt.pix.pixelformat;
> +	for (int i=0; i<4; i++) {
> +		printf("%c", f & 0xff);
> +		f >>= 8;
> +	}
> +	printf("\n");
> +}
> +
> +pixel buf_pixel(struct v4l2_format *fmt, unsigned char *buf, int x, int y)
> +{
> +	pixel p = { 0, 0, 0, 0 };
> +	int pos = x + y*fmt->fmt.pix.width;
> +	int b;
> +
> +	p.alpha = 128;
> +
> +	switch (fmt->fmt.pix.pixelformat) {
> +	case '01AB': /* BA10, aka GRBG10, 
> +			https://www.linuxtv.org/downloads/v4l-dvb-apis-new/uapi/v4l/pixfmt-srggb10.html?highlight=ba10
> +		     */
> +		b = buf[pos*2];
> +		b += buf[pos*2+1] << 8;
> +		b /= 4;
> +		if ((y % 2) == 0) {
> +			switch (x % 2) {
> +			case 0: p.g = b/2; break;
> +			case 1: p.r = b; break;
> +			}
> +		} else {
> +			switch (x % 2) {
> +			case 0: p.b = b; break;
> +			case 1: p.g = b/2; break;
> +			}
> +		}
> +		break;
> +
> +	case V4L2_PIX_FMT_RGB24:
> +		pos *= 4;
> +		p.r = buf[pos];
> +		p.g = buf[pos+1];
> +		p.b = buf[pos+2];
> +		break;
> +
> +	default:
> +		printf("Wrong pixel format!\n");
> +		fmt_print(fmt);
> +		exit(1);
> +	}
> +
> +	return p;
> +}
> +
> +void sdl_render(struct sdl *m, unsigned char *buf, struct v4l2_format *fmt)
> +{
> +	if (!m->window) 
> +		return;
> +	sdl_begin_paint(m);    
> +	/* do your rendering here */
> +
> +	for (int y = 0; y < m->sy; y++)
> +		for (int x = 0; x < m->sx; x++) {
> +			pixel p = buf_pixel(fmt, buf, x*m->factor, y*m->factor);
> +			p.alpha = 128;
> +			sfc_put_pixel(m->liveview, x, y, &p);
> +		}
> +
> +	//render_statistics(liveview);
> +
> +	sdl_finish_paint(m);
> +}
> +
> +#if 0
> +void imageStatistics(FCam::Image img)
> +{
> +	int sx, sy;
> +
> +	sx = img.size().width;                                                          
> +	sy = img.size().height;                                                         
> +	printf("Image is %d x %d, ", sx, sy);                                           
> +
> +	printf("(%d) ", img.brightness(sx/2, sy/2));
> +
> +	int dark = 0;                                                                   
> +	int bright = 0;                                                                 
> +	int total = 0;                                                                  
> +#define RATIO 10
> +	for (int y = sy/(2*RATIO); y < sy; y += sy/RATIO)                               
> +		for (int x = sx/(2*RATIO); x < sx; x += sx/RATIO) {                    
> +			int br = img.brightness(x, y);                               
> +
> +			if (!d_raw) {
> +				/* It seems real range is 60 to 218 */
> +				if (br > 200)
> +					bright++;                                               
> +				if (br < 80)
> +					dark++;
> +			} else {
> +				/* there's a lot of noise, it seems black is commonly 65..71,
> +				   bright is cca 1023 */
> +				if (br > 1000)
> +					bright++;
> +				if (br < 75)
> +					dark++;
> +			}
> +			total++;                                                      
> +		}
> +
> +	printf("%d dark %d bri,", dark, bright);                     
> +
> +	long sharp = 0;
> +	for (int y = sy/3; y < 2*(sy/3); y+=sy/12) {
> +		int b = -1;
> +		for (int x = sx/3; x < 2*(sx/3); x++) {
> +			int b2;                                                                
> +			b2 = img.brightness(x, y/2);                                          
> +			if (b != -1)
> +				sharp += (b-b2) * (b-b2);                                              
> +			b = b2;                                                                
> +		}
> +	}
> +	printf("sh %d\n", sharp);
> +}
> +#endif
> +
> +
> +void sdl_init(struct sdl *m, int _sx, int _sy, int _factor)
> +{
> +	printf("Initing SDL\n");
> +
> +	if (SDL_Init(SDL_INIT_VIDEO) < 0) {
> +		printf("Could not init SDL\n");
> +		exit(1);
> +	}
> +
> +	atexit(SDL_Quit);
> +
> +	m->wx = 800;
> +	m->wy = 400;
> +
> +	m->window = SDL_CreateWindow( "Camera", SDL_WINDOWPOS_UNDEFINED,
> +				      SDL_WINDOWPOS_UNDEFINED, m->wx, m->wy,
> +				      SDL_WINDOW_SHOWN );
> +	if (m->window == NULL) {
> +		printf( "Window could not be created! SDL_Error: %s\n", SDL_GetError() );
> +	}
> +
> +	m->screen = SDL_GetWindowSurface(m->window);
> +	if (!m->screen) {
> +		printf("Couldn't create liveview\n");
> +		exit(1);
> +	}
> +
> +	m->sx = _sx;
> +	m->sy = _sy;
> +	m->factor = _factor;
> +
> +	m->sx /= m->factor;
> +	m->sy /= m->factor;
> +    
> +	m->focus = 0;
> +	m->gain = 0;
> +	m->exposure = 0;
> +
> +	m->bx = (m->wx-m->sx)/2;
> +	m->by = (m->wy-m->sy)/2;
> +
> +	m->liveview = SDL_CreateRGBSurface(0,m->sx,m->sy,32,0,0,0,0);
> +	if (!m->liveview) {
> +		printf("Couldn't create liveview\n");
> +		exit(1);
> +	}
> +	sdl_paint_ui(m);
> +}
> diff --git a/lib/libv4lconvert/libv4lconvert.c b/lib/libv4lconvert/libv4lconvert.c
> index d3d8936..7521ec8 100644
> --- a/lib/libv4lconvert/libv4lconvert.c
> +++ b/lib/libv4lconvert/libv4lconvert.c
> @@ -1205,6 +1205,8 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
>  			v4lconvert_swap_uv(src, dest, fmt);
>  			break;
>  		}
> +		default:
> +		  /* This is bad, fixme? */
>  		break;
>  
>  	case V4L2_PIX_FMT_YVU420:
> @@ -1228,6 +1230,8 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
>  		case V4L2_PIX_FMT_YVU420:
>  			memcpy(dest, src, width * height * 3 / 2);
>  			break;
> +		default:
> +		  /* This is bad, fixme? */
>  		}
>  		break;
>  
> diff --git a/utils/decode_tm6000/Makefile.am b/utils/decode_tm6000/Makefile.am
> index ac4e85e..f059e3c 100644
> --- a/utils/decode_tm6000/Makefile.am
> +++ b/utils/decode_tm6000/Makefile.am
> @@ -1,4 +1,4 @@
>  bin_PROGRAMS = decode_tm6000
>  decode_tm6000_SOURCES = decode_tm6000.c
> -decode_tm6000_LDADD = ../libv4l2util/libv4l2util.la
> +decode_tm6000_LDADD = ../libv4l2/libv4l2.la
>  decode_tm6000_LDFLAGS = $(ARGP_LIBS)
> diff --git a/utils/decode_tm6000/decode_tm6000.c b/utils/decode_tm6000/decode_tm6000.c
> index 4bffbdd..fda7e3b 100644
> --- a/utils/decode_tm6000/decode_tm6000.c
> +++ b/utils/decode_tm6000/decode_tm6000.c

Everything below it is completely wrong!

> @@ -1,365 +1,16 @@
> -/*
> -   decode_tm6000.c - decode multiplexed format from TM5600/TM6000 USB
> +/* gcc asciicam.c /usr/lib/i386-linux-gnu/libv4l2.so.0.0.0 -o asciicam
> +   gcc asciicam.c /usr/lib/arm-linux-gnueabi/libv4l2.so.0 -o asciicam
>  
> -   Copyright (C) 2007 Mauro Carvalho Chehab <mchehab@infradead.org>
> -
> -   This program is free software; you can redistribute it and/or modify
> -   it under the terms of the GNU General Public License as published by
> -   the Free Software Foundation version 2.
> -
> -   This program is distributed in the hope that it will be useful,
> -   but WITHOUT ANY WARRANTY; without even the implied warranty of
> -   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> -   GNU General Public License for more details.
> -
> -   You should have received a copy of the GNU General Public License
> -   along with this program; if not, write to the Free Software
> -   Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA.
> +gcc -std=gnu99 -DHAVE_CONFIG_H -I. -I../.. -fvisibility=hidden -I../../lib/include -Wall -Wpointer-arith -D_GNU_SOURCE -I../../include -g -O2 asciicam.c libv4l2.c /usr/lib/arm-linux-gnueabi/libv4lconvert.so.0 log.c v4l2convert.c v4l2-plugin.c -o asciicam
>   */
> -#include "../libv4l2util/v4l2_driver.h"
>  #include <stdio.h>
> -#include <string.h>
> -#include <argp.h>
> -#include <unistd.h>
>  #include <sys/types.h>
>  #include <sys/stat.h>
>  #include <fcntl.h>
> -#include <stdlib.h>
> -#include <errno.h>
> -
> -const char *argp_program_version="decode_tm6000 version 0.0.1";
> -const char *argp_program_bug_address="Mauro Carvalho Chehab <mchehab@infradead.org>";
> -const char doc[]="Decodes tm6000 proprietary format streams";
> -const struct argp_option options[] = {
> -	{"verbose",	'v',	0,	0,	"enables debug messages", 0},
> -	{"device",	'd',	"DEV",	0,	"uses device for reading", 0},
> -	{"output",	'o',	"FILE",	0,	"outputs raw stream to a file", 0},
> -	{"input",	'i',	"FILE",	0,	"parses a file, instead of a device", 0},
> -	{"freq",	'f',	"Freq",	0,	"station frequency, in MHz (default is 193.25)", 0},
> -	{"nbufs",	'n',	"quant",0,	"number of video buffers", 0},
> -	{"audio",	'a',	0,	0,	"outputs audio on stdout", 0},
> -	{"read",	'r',	0,	0,	"use read() instead of mmap method", 0},
> -	{ 0, 0, 0, 0, 0, 0 }
> -};
> -
> -static char outbuf[692224];
> -static int debug=0, audio=0, use_mmap=1, nbufs=4;
> -static float freq_mhz=193.25;
> -static char *devicename="/dev/video0";
> -static char *filename=NULL;
> -static enum {
> -	NORMAL,
> -	INPUT,
> -	OUTPUT
> -} mode = NORMAL;
> -
> -static FILE *fout;
> -
> -//const char args_doc[]="ARG1 ARG2";
> -
> -static error_t parse_opt (int key, char *arg, struct argp_state *state)
> -{
> -	switch (key) {
> -	case 'a':
> -		audio++;
> -		break;
> -	case 'r':
> -		use_mmap=0;
> -		break;
> -	case 'v':
> -		debug++;
> -		break;
> -	case 'd':
> -		devicename=arg;
> -		break;
> -	case 'i':
> -	case 'o':
> -		if (mode!=NORMAL) {
> -			argp_error(state,"You can't use input/output options simultaneously.\n");
> -			break;
> -		}
> -		if (key=='i')
> -			mode=INPUT;
> -		else
> -			mode=OUTPUT;
> -
> -		filename=arg;
> -		break;
> -	case 'f':
> -		freq_mhz=atof(arg);
> -		break;
> -	case 'n':
> -		nbufs=atoi(arg);
> -		if  (nbufs<2)
> -			nbufs=2;
> -		break;
> -	default:
> -		return ARGP_ERR_UNKNOWN;
> -	}
> -	return 0;
> -}
> -
> -static struct argp argp = {
> -	.options=options,
> -	.parser=parse_opt,
> -	.args_doc=NULL,
> -	.doc=doc,
> -};
>  
> -#define TM6000_URB_MSG_LEN 180
> -enum {
> -	TM6000_URB_MSG_VIDEO=1,
> -	TM6000_URB_MSG_AUDIO,
> -	TM6000_URB_MSG_VBI,
> -	TM6000_URB_MSG_PTS,
> -	TM6000_URB_MSG_ERR,
> -};
> -
> -const char *tm6000_msg_type[]= {
> -	"unknown(0)",	//0
> -	"video",	//1
> -	"audio",	//2
> -	"vbi",		//3
> -	"pts",		//4
> -	"err",		//5
> -	"unknown(6)",	//6
> -	"unknown(7)",	//7
> -};
> -
> -#define dprintf(fmt,arg...) \
> -	if (debug) fprintf(stderr, fmt, ##arg)
> -
> -static int recebe_buffer (struct v4l2_buffer *v4l2_buf, struct v4l2_t_buf *buf)
> -{
> -	dprintf("Received %zd bytes\n", buf->length);
> -fflush(stdout);
> -	memcpy (outbuf,buf->start,buf->length);
> -	return buf->length;
> -}
> -
> -
> -static int prepare_read (struct v4l2_driver *drv)
> -{
> -	struct v4l2_format fmt;
> -	double freq;
> -	int rc;
> -
> -	memset (drv,0,sizeof(*drv));
> -
> -	if (v4l2_open (devicename, 1,drv)<0) {
> -		perror ("Error opening dev");
> -		return -1;
> -	}
> -
> -	memset (&fmt,0,sizeof(fmt));
> -
> -	uint32_t pixelformat=V4L2_PIX_FMT_TM6000;
> -
> -	if (v4l2_gettryset_fmt_cap (drv,V4L2_SET,&fmt, 720, 480,
> -				    pixelformat,V4L2_FIELD_ANY)) {
> -		perror("set_input to tm6000 raw format");
> -		return -1;
> -	}
> -
> -	if (freq_mhz) {
> -		freq=freq_mhz * 1000 * 1000;
> -		rc=v4l2_getset_freq (drv,V4L2_SET, &freq);
> -		if (rc<0)
> -			printf ("Cannot set freq to %.3f MHz\n",freq_mhz);
> -	}
> -
> -	if (use_mmap) {
> -		printf("Preparing for receiving frames on %d buffers...\n",nbufs);
> -		fflush (stdout);
> -
> -		rc=v4l2_mmap_bufs(drv, nbufs);
> -		if (rc<0) {
> -			printf ("Cannot mmap %d buffers\n",nbufs);
> -			return -1;
> -		}
> -
> -//		v4l2_stop_streaming(&drv);
> -		rc=v4l2_start_streaming(drv);
> -		if (rc<0) {
> -			printf ("Cannot start streaming\n");
> -			return -1;
> -		}
> -	}
> -	printf("Waiting for frames...\n");
> -
> -	return 0;
> -}
> +#include <linux/videodev2.h>
>  
> -static int read_stream (struct v4l2_driver *drv, int fd)
> +void main(void)
>  {
> -	if (use_mmap) {
> -		fd_set fds;
> -		struct timeval tv;
> -		int r;
> -
> -		FD_ZERO (&fds);
> -		FD_SET (fd, &fds);
> -
> -		/* Timeout. */
> -		tv.tv_sec = 2;
> -		tv.tv_usec = 0;
> -
> -		r = select (fd + 1, &fds, NULL, NULL, &tv);
> -		if (-1 == r) {
> -			if (EINTR == errno) {
> -				perror ("select");
> -				return -errno;
> -			}
> -		}
> -
> -		if (0 == r) {
> -			fprintf (stderr, "select timeout\n");
> -			return -errno;
> -		}
> -
> -		return v4l2_rcvbuf(drv, recebe_buffer);
> -	} else {
> -		int size=read(fd, outbuf, sizeof(outbuf));
> -		return size;
> -	}
> -
> -	return 0;
> -}
> -
> -static int read_char (struct v4l2_driver *drv, int fd)
> -{
> -	static int sizebuf=0;
> -	static unsigned char *p=NULL;
> -	unsigned char c;
> -
> -	if (sizebuf<=0) {
> -		sizebuf=read_stream(drv,fd);
> -		if (sizebuf<=0)
> -			return -1;
> -		p=(unsigned char *)outbuf;
> -	}
> -	c=*p;
> -	p++;
> -	sizebuf--;
> -
> -	return c;
> -}
> -
> -
> -int main (int argc, char*argv[])
> -{
> -	int fd;
> -	unsigned int i;
> -	unsigned char buf[TM6000_URB_MSG_LEN], img[720*2*480];
> -	unsigned int  cmd, size, field, block, line, pos=0;
> -	unsigned long header=0;
> -	int           linesize=720*2,skip=0;
> -	struct v4l2_driver drv;
> -
> -	argp_parse (&argp, argc, argv, 0, 0, 0);
> -
> -	if (mode!=INPUT) {
> -		if (prepare_read (&drv)<0)
> -			return -1;
> -		fd=drv.fd;
> -	} else {
> -		/*mode == INPUT */
> -
> -		fd=open(filename,O_RDONLY);
> -		if (fd<0) {
> -			perror ("error opening a file for parsing");
> -			return -1;
> -		}
> -		dprintf("file %s opened for parsing\n",filename);
> -		use_mmap=0;
> -	}
> -
> -	if (mode==OUTPUT) {
> -		fout=fopen(filename,"w");
> -		if (!fout) {
> -			perror ("error opening a file to write");
> -			return -1;
> -		}
> -		dprintf("file %s opened for output\n",filename);
> -
> -		do {
> -			size=read_stream (&drv,fd);
> -
> -			if (size<=0) {
> -				close (fd);
> -				return -1;
> -			}
> -			dprintf("writing %d bytes\n",size);
> -			fwrite(outbuf,1, size,fout);
> -//			fflush(fout);
> -		} while (1);
> -	}
> -
> -
> -	while (1) {
> -		skip=0;
> -		header=0;
> -		do {
> -			int c;
> -			c=read_char (&drv,fd);
> -			if (c<0) {
> -				perror("read");
> -				return -1;
> -			}
> -
> -			header=(header>>8)&0xffffff;  
> -			header=header|(c<<24);
> -			skip++;
> -		} while ( (((header>>24)&0xff) != 0x47) );
> -
> -		/* split the header fields */
> -		size  = (((header & 0x7e)<<1) -1) * 4;
> -		block = (header>>7) & 0xf;
> -		field = (header>>11) & 0x1;
> -		line  = (header>>12) & 0x1ff;
> -		cmd   = (header>>21) & 0x7;
> -
> -		/* Read the remaining buffer */
> -		for (i=0;i<sizeof(buf);i++) {
> -			int c;
> -			c=read_char (&drv,fd);
> -			if (c<0) {
> -				perror("read");
> -				return -1;
> -			}
> -			buf[i]=c;
> -		}
> -
> -		/* FIXME: Mounts the image as field0+field1
> -			* It should, instead, check if the user selected
> -			* entrelaced or non-entrelaced mode
> -			*/
> -		pos=((line<<1)+field)*linesize+
> -					block*TM6000_URB_MSG_LEN;
> -
> -			/* Prints debug info */
> -		dprintf("0x%08x (skip %d), %s size=%d, line=%d, field=%d, block=%d\n",
> -				(unsigned int)header, skip,
> -				 tm6000_msg_type[cmd],
> -				 size, line, field, block);
> -
> -		/* Don't allow to write out of the buffer */
> -		if (pos+sizeof(buf) > sizeof(img))
> -			cmd = TM6000_URB_MSG_ERR;
> -
> -		/* handles each different URB message */
> -		switch(cmd) {
> -		case TM6000_URB_MSG_VIDEO:
> -			/* Fills video buffer */
> -			memcpy(buf,&img[pos],sizeof(buf));
> -		case TM6000_URB_MSG_AUDIO:
> -			if (audio)
> -				fwrite(buf,sizeof(buf),1,stdout);
> -//		case TM6000_URB_MSG_VBI:
> -//		case TM6000_URB_MSG_PTS:
> -		break;
> -		}
> -	}
> -	close(fd);
> -	return 0;
> +  v4l2_close(-2);
>  }
> 



Thanks,
Mauro

Re: support autofocus / autogain in libv4l2

[Pavel Machek]

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Hi!

> > For focus to be useful, we need autofocus implmented
> > somewhere. Unfortunately, v4l framework does not seem to provide good
> > place where to put autofocus. I believe, long-term, we'll need some
> > kind of "video server" providing this kind of services.
> > 
> > Anyway, we probably don't want autofocus in kernel (even through some
> > cameras do it in hardware), and we probably don't want autofocus in
> > each and every user application.
> > 
> > So what remains is libv4l2. 
> 
> IMO, the best place for autofocus is at libv4l2. Putting it on a
> separate "video server" application looks really weird for me.

Well... let me see. libraries are quite limited -- it is hard to open
files, or use threads/have custom main loop. It may be useful to
switch resolutions -- do autofocus/autogain at lower resolution, then
switch to high one for taking picture. It would be good to have that
in "system" code, but I'm not at all sure libv4l2 design will allow
that.

It would be good if application could say "render live camera into
this window" and only care about user interface, then say "give me a
high resolution jpeg". But that would require main loop in the
library...

It would be nice if more than one application could be accessing the
camera at the same time... (I.e. something graphical running preview
then using command line tool to grab a picture.) This one is
definitely not solveable inside a library...

> Btw, libv4l2 already has some autotools for auto gain and auto
> white balance. See the implementation under:
> 	lib/libv4lconvert/processing
> 
> The libv4l internal controls can be seen at:
> 	lib/libv4lconvert/control/libv4lcontrol.h
> 
> The ones implemented by the processing part of the library are:

Thanks for pointer, will take a look.

> > Now, this is in no way clean or complete,
> > and functionality provided by sdl.c and asciicam.c probably _should_
> > be in application, but... I'd like to get the code out there.
> > 
> > Oh and yes, I've canibalized decode_tm6000.c application instead of
> > introducing my own. Autotools scare me, sorry.
> 
> Why replace decode_tm6000.c by something else? If you want to add another
> test application, just place it on a new file.

Scary scary scary autotools ;-). Yes, I did rather lot of hacks, as
you noted below. I do development on n900, so not everything is easy.

> I added a few notes together with the code, pointing the main things
> I think it require changes, in order for me to do a better review
> at the code. I didn't test nor tried to check the algorithms inside,
> as the code, on its current state, requires rework and code cleanup.

Thanks, I'll take a look.

> Please don't add a new application under lib/. It is fine if you want
> some testing application, if the ones there aren't enough, but please
> place it under contrib/test/.
> 
> You should likely take a look at v4l2grab first, as it could have
> almost everything you would need.

Will take a look, thanks for pointer.

> IMHO, it would be better to use aalib. Btw, xawtv3 has a code example
> using it, under:
> 	console/ttv.c
> 
> As it already uses libv4l, prhaps you could use it, instead of adding
> a new ascii app.

No need to duplicate it, then. I was trying to quickly test video
works, this was before SDL.

> > +#include "sdl.c"
> > +
> > +static struct sdl sdl;
> > +
> > +int v4l2_get_index(int fd);
> > +void my_main(void);
> > +
> 
> The above looks really odd. Why do you want to make libv4l2 dependent
> on sdl?

I don't, but I had some nasty problems with linker; this should really
go into application but it refused to link. Scary libtool.

> > +static void v4l2_histogram(unsigned char *buf, int cdf[], struct v4l2_format *fmt)
> > +{
> > +    for (int y = 0; y < fmt->fmt.pix.height; y+=19)
> > +      for (int x = 0; x < fmt->fmt.pix.width; x+=19) {
> > +	pixel p = buf_pixel(fmt, buf, x, y);
> > +	
> > +	int b;
> > +	/* HACK: we divide green by 2 to have nice picture, undo it here. */
> > +	b = p.r + 2*p.g + p.b;
> > +	b = (b * BUCKETS)/(256);
> > +	cdf[b]++;
> > +      }
> > +}
> > +
> > +static long v4l2_sharpness(unsigned char *buf, struct v4l2_format *fmt)
> > +{
> > +  int h = fmt->fmt.pix.height;
> > +  int w = fmt->fmt.pix.width;
> > +  long r = 0;
> > +
> > +    for (int y = h/3; y < h-h/3; y+=h/9)
> > +      for (int x = w/3; x < w-w/3; x++) {
> > +	pixel p1 = buf_pixel(fmt, buf, x, y);
> > +	pixel p2 = buf_pixel(fmt, buf, x+2, y);
> > +	
> > +	int b1, b2;
> > +	/* HACK: we divide green by 2 to have nice picture, undo it here. */
> > +	b1 = p1.r + 2*p1.g + p1.b;
> > +	b2 = p2.r + 2*p2.g + p2.b;
> > +
> > +	int v;
> > +	v = (b1-b2)*(b1-b2);
> > +	if (v > 36)
> > +		r+=v;
> > +      }
> > +
> > +    return r;
> > +}
> 
> IMO, the above belongs to a separate processing module under
> 	lib/libv4lconvert/processing/

I guess so.

> > +
> > +int v4l2_set_exposure(int fd, int exposure)
> > +{
> > +	int index = v4l2_get_index(fd);
> > +
> > +	if (index == -1 || devices[index].convert == NULL) {
> > +		V4L2_LOG_ERR("v4l2_set_exposure called with invalid fd: %d\n", fd);
> > +		errno = EBADF;
> > +		return -1;
> > +	}
> > +
> > +	struct v4l2_control ctrl;
> > +	ctrl.id = V4L2_CID_EXPOSURE;
> > +	ctrl.value = exposure;
> > +	if (ioctl(devices[index].subdev_fds[0], VIDIOC_S_CTRL, &ctrl) < 0) {
> > +	  printf("Could not set exposure\n");
> > +	}
> > +	return 0;
> > +}
> 
> Shouldn't it be together with lib/libv4lconvert/processing/autogain.c,
> perhaps as an alternative implementation, if what's there is not
> enough?

I'll take a look, thanks.

> > @@ -823,6 +1246,10 @@ int v4l2_close(int fd)
> >  {
> >  	int index, result;
> >  
> > +	if (fd == -2) {
> > +	  my_main();
> > +	}
> > +
> 
> That looks a hack!

That is _the_ hack ;-). Yes, agreed, need to look at
processing/. .. when I get time.


> > +#include <SDL2/SDL.h>
> > +#include <SDL2/SDL_image.h>
> 
> If you're adding a SDL-specific application, you'll need to add the 
> needed autoconf bits to detect if SDL devel package is installed,
> auto-disabling it if not.
> 
> Yet, I don't think that SDL should be part of the library, but,
> instead, part of some application.

Agreed. libtool prevented me from doing the right thing.

> > index 4bffbdd..fda7e3b 100644
> > --- a/utils/decode_tm6000/decode_tm6000.c
> > +++ b/utils/decode_tm6000/decode_tm6000.c
> 
> Everything below it is completely wrong!

And most of the stuff above is, too :-). I wanted to get the code out
in case I won't have time...

Thanks,
									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: support autofocus / autogain in libv4l2

[Mauro Carvalho Chehab]

Em Mon, 24 Apr 2017 23:29:14 +0200
Pavel Machek <pavel@ucw.cz> escreveu:

> Hi!
> 
> > > For focus to be useful, we need autofocus implmented
> > > somewhere. Unfortunately, v4l framework does not seem to provide good
> > > place where to put autofocus. I believe, long-term, we'll need some
> > > kind of "video server" providing this kind of services.
> > > 
> > > Anyway, we probably don't want autofocus in kernel (even through some
> > > cameras do it in hardware), and we probably don't want autofocus in
> > > each and every user application.
> > > 
> > > So what remains is libv4l2.   
> > 
> > IMO, the best place for autofocus is at libv4l2. Putting it on a
> > separate "video server" application looks really weird for me.  
> 
> Well... let me see. libraries are quite limited -- it is hard to open
> files, or use threads/have custom main loop. It may be useful to
> switch resolutions -- do autofocus/autogain at lower resolution, then
> switch to high one for taking picture. It would be good to have that
> in "system" code, but I'm not at all sure libv4l2 design will allow
> that.

I don't see why it would be hard to open files or have threads inside
a library. There are several libraries that do that already, specially
the ones designed to be used on multimidia apps.

Resolution switch can indeed be a problem on devices that use MC
and subdev API, as a plugin would be required to teach the library
about N9 specifics (or the Kernel API should be improved to let
a generic application to better detect the hardware capabilities).

> It would be good if application could say "render live camera into
> this window" and only care about user interface, then say "give me a
> high resolution jpeg". But that would require main loop in the
> library...

Nothing prevents writing an upper layer on the top of libv4l in
order to provide such kind of functions.

> It would be nice if more than one application could be accessing the
> camera at the same time... (I.e. something graphical running preview
> then using command line tool to grab a picture.) This one is
> definitely not solveable inside a library...

Someone once suggested to have something like pulseaudio for V4L.
For such usage, a server would be interesting. Yet, I would code it
in a way that applications using libv4l will talk with such daemon
in a transparent way.

> > The above looks really odd. Why do you want to make libv4l2 dependent
> > on sdl?  
> 
> I don't, but I had some nasty problems with linker; this should really
> go into application but it refused to link. Scary libtool.

That's weird. 


> > If you're adding a SDL-specific application, you'll need to add the 
> > needed autoconf bits to detect if SDL devel package is installed,
> > auto-disabling it if not.
> > 
> > Yet, I don't think that SDL should be part of the library, but,
> > instead, part of some application.  
> 
> Agreed. libtool prevented me from doing the right thing.

if you add libSDL detection at configure.ac, you likely won't need to
deal with libtool.

On a quick look at web, it seems that there's a m4 module that does
the right thing, according with:
	https://wiki.libsdl.org/FAQLinux


Thanks,
Mauro

Re: support autofocus / autogain in libv4l2

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 2684 bytes --]

Hi!

> > > > For focus to be useful, we need autofocus implmented
> > > > somewhere. Unfortunately, v4l framework does not seem to provide good
> > > > place where to put autofocus. I believe, long-term, we'll need some
> > > > kind of "video server" providing this kind of services.
> > > > 
> > > > Anyway, we probably don't want autofocus in kernel (even through some
> > > > cameras do it in hardware), and we probably don't want autofocus in
> > > > each and every user application.
> > > > 
> > > > So what remains is libv4l2.   
> > > 
> > > IMO, the best place for autofocus is at libv4l2. Putting it on a
> > > separate "video server" application looks really weird for me.  
> > 
> > Well... let me see. libraries are quite limited -- it is hard to open
> > files, or use threads/have custom main loop. It may be useful to
> > switch resolutions -- do autofocus/autogain at lower resolution, then
> > switch to high one for taking picture. It would be good to have that
> > in "system" code, but I'm not at all sure libv4l2 design will allow
> > that.
> 
> I don't see why it would be hard to open files or have threads inside
> a library. There are several libraries that do that already, specially
> the ones designed to be used on multimidia apps.

Well, fd's are hard, because application can do fork() and now
interesting stuff happens. Threads are tricky, because now you have
locking etc.

libv4l2 is designed to be LD_PRELOADED. That is not really feasible
with "complex" library.

> > It would be good if application could say "render live camera into
> > this window" and only care about user interface, then say "give me a
> > high resolution jpeg". But that would require main loop in the
> > library...
> 
> Nothing prevents writing an upper layer on the top of libv4l in
> order to provide such kind of functions.

Agreed.

> > It would be nice if more than one application could be accessing the
> > camera at the same time... (I.e. something graphical running preview
> > then using command line tool to grab a picture.) This one is
> > definitely not solveable inside a library...
> 
> Someone once suggested to have something like pulseaudio for V4L.
> For such usage, a server would be interesting. Yet, I would code it
> in a way that applications using libv4l will talk with such daemon
> in a transparent way.

Yes, we need something like pulseaudio for V4L. And yes, we should
make it transparent for applications using libv4l.

Regards,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: support autofocus / autogain in libv4l2

[Pali Rohár]

On Tuesday 25 April 2017 10:05:38 Pavel Machek wrote:
> > > It would be nice if more than one application could be accessing the
> > > camera at the same time... (I.e. something graphical running preview
> > > then using command line tool to grab a picture.) This one is
> > > definitely not solveable inside a library...
> > 
> > Someone once suggested to have something like pulseaudio for V4L.
> > For such usage, a server would be interesting. Yet, I would code it
> > in a way that applications using libv4l will talk with such daemon
> > in a transparent way.
> 
> Yes, we need something like pulseaudio for V4L. And yes, we should
> make it transparent for applications using libv4l.

IIRC there is already some effort in writing such "video" server which
would support accessing more application into webcam video, like
pulseaudio server for accessing more applications to microphone input.

-- 
Pali Rohár
pali.rohar@gmail.com

Re: support autofocus / autogain in libv4l2

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 1215 bytes --]

Hi!
On Tue 2017-04-25 10:08:15, Pali Rohár wrote:
> On Tuesday 25 April 2017 10:05:38 Pavel Machek wrote:
> > > > It would be nice if more than one application could be accessing the
> > > > camera at the same time... (I.e. something graphical running preview
> > > > then using command line tool to grab a picture.) This one is
> > > > definitely not solveable inside a library...
> > > 
> > > Someone once suggested to have something like pulseaudio for V4L.
> > > For such usage, a server would be interesting. Yet, I would code it
> > > in a way that applications using libv4l will talk with such daemon
> > > in a transparent way.
> > 
> > Yes, we need something like pulseaudio for V4L. And yes, we should
> > make it transparent for applications using libv4l.
> 
> IIRC there is already some effort in writing such "video" server which
> would support accessing more application into webcam video, like
> pulseaudio server for accessing more applications to microphone input.

Do you have project name / url / something?

Thanks,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: support autofocus / autogain in libv4l2

[Pali Rohár]

On Tuesday 25 April 2017 13:23:30 Pavel Machek wrote:
> Hi!
> On Tue 2017-04-25 10:08:15, Pali Rohár wrote:
> > On Tuesday 25 April 2017 10:05:38 Pavel Machek wrote:
> > > > > It would be nice if more than one application could be accessing the
> > > > > camera at the same time... (I.e. something graphical running preview
> > > > > then using command line tool to grab a picture.) This one is
> > > > > definitely not solveable inside a library...
> > > > 
> > > > Someone once suggested to have something like pulseaudio for V4L.
> > > > For such usage, a server would be interesting. Yet, I would code it
> > > > in a way that applications using libv4l will talk with such daemon
> > > > in a transparent way.
> > > 
> > > Yes, we need something like pulseaudio for V4L. And yes, we should
> > > make it transparent for applications using libv4l.
> > 
> > IIRC there is already some effort in writing such "video" server which
> > would support accessing more application into webcam video, like
> > pulseaudio server for accessing more applications to microphone input.
> 
> Do you have project name / url / something?

Pinos (renamed from PulseVideo)

https://blogs.gnome.org/uraeus/2015/06/30/introducing-pulse-video/
https://cgit.freedesktop.org/~wtay/pinos/

But from git history it looks like it is probably dead now...

-- 
Pali Rohár
pali.rohar@gmail.com

Re: support autofocus / autogain in libv4l2

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 1726 bytes --]

On Tue 2017-04-25 13:30:09, Pali Rohár wrote:
> On Tuesday 25 April 2017 13:23:30 Pavel Machek wrote:
> > Hi!
> > On Tue 2017-04-25 10:08:15, Pali Rohár wrote:
> > > On Tuesday 25 April 2017 10:05:38 Pavel Machek wrote:
> > > > > > It would be nice if more than one application could be accessing the
> > > > > > camera at the same time... (I.e. something graphical running preview
> > > > > > then using command line tool to grab a picture.) This one is
> > > > > > definitely not solveable inside a library...
> > > > > 
> > > > > Someone once suggested to have something like pulseaudio for V4L.
> > > > > For such usage, a server would be interesting. Yet, I would code it
> > > > > in a way that applications using libv4l will talk with such daemon
> > > > > in a transparent way.
> > > > 
> > > > Yes, we need something like pulseaudio for V4L. And yes, we should
> > > > make it transparent for applications using libv4l.
> > > 
> > > IIRC there is already some effort in writing such "video" server which
> > > would support accessing more application into webcam video, like
> > > pulseaudio server for accessing more applications to microphone input.
> > 
> > Do you have project name / url / something?
> 
> Pinos (renamed from PulseVideo)
> 
> https://blogs.gnome.org/uraeus/2015/06/30/introducing-pulse-video/
> https://cgit.freedesktop.org/~wtay/pinos/
> 
> But from git history it looks like it is probably dead now...

Actually, last commit is an hour ago on "work" branch. Seems alive to
me ;-).

Thanks for pointer...
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: support autofocus / autogain in libv4l2

[Pali Rohár]

On Tuesday 25 April 2017 14:28:20 Pavel Machek wrote:
> On Tue 2017-04-25 13:30:09, Pali Rohár wrote:
> > On Tuesday 25 April 2017 13:23:30 Pavel Machek wrote:
> > > Hi!
> > > On Tue 2017-04-25 10:08:15, Pali Rohár wrote:
> > > > On Tuesday 25 April 2017 10:05:38 Pavel Machek wrote:
> > > > > > > It would be nice if more than one application could be accessing the
> > > > > > > camera at the same time... (I.e. something graphical running preview
> > > > > > > then using command line tool to grab a picture.) This one is
> > > > > > > definitely not solveable inside a library...
> > > > > > 
> > > > > > Someone once suggested to have something like pulseaudio for V4L.
> > > > > > For such usage, a server would be interesting. Yet, I would code it
> > > > > > in a way that applications using libv4l will talk with such daemon
> > > > > > in a transparent way.
> > > > > 
> > > > > Yes, we need something like pulseaudio for V4L. And yes, we should
> > > > > make it transparent for applications using libv4l.
> > > > 
> > > > IIRC there is already some effort in writing such "video" server which
> > > > would support accessing more application into webcam video, like
> > > > pulseaudio server for accessing more applications to microphone input.
> > > 
> > > Do you have project name / url / something?
> > 
> > Pinos (renamed from PulseVideo)
> > 
> > https://blogs.gnome.org/uraeus/2015/06/30/introducing-pulse-video/
> > https://cgit.freedesktop.org/~wtay/pinos/
> > 
> > But from git history it looks like it is probably dead now...
> 
> Actually, last commit is an hour ago on "work" branch. Seems alive to
> me ;-).

Great! I just (blindly) looked at master branch and it is old...

> Thanks for pointer...
> 									Pavel

-- 
Pali Rohár
pali.rohar@gmail.com

Re: support autofocus / autogain in libv4l2

[Nicolas Dufresne]

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Le mardi 25 avril 2017 à 13:30 +0200, Pali Rohár a écrit :
> Pinos (renamed from PulseVideo)
> 
> https://blogs.gnome.org/uraeus/2015/06/30/introducing-pulse-video/
> https://cgit.freedesktop.org/~wtay/pinos/
> 
> But from git history it looks like it is probably dead now...

This is also incorrect. See "work" branch. It is still a one man show,
code being aggressively re-factored. I suspect this will be the case
until the "form" is considered acceptable.

Nicolas

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Re: support autofocus / autogain in libv4l2

[Nicolas Dufresne]

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Le mardi 25 avril 2017 à 10:08 +0200, Pali Rohár a écrit :
> On Tuesday 25 April 2017 10:05:38 Pavel Machek wrote:
> > > > It would be nice if more than one application could be
> > > > accessing the
> > > > camera at the same time... (I.e. something graphical running
> > > > preview
> > > > then using command line tool to grab a picture.) This one is
> > > > definitely not solveable inside a library...
> > > 
> > > Someone once suggested to have something like pulseaudio for V4L.
> > > For such usage, a server would be interesting. Yet, I would code
> > > it
> > > in a way that applications using libv4l will talk with such
> > > daemon
> > > in a transparent way.
> > 
> > Yes, we need something like pulseaudio for V4L. And yes, we should
> > make it transparent for applications using libv4l.
> 
> IIRC there is already some effort in writing such "video" server
> which
> would support accessing more application into webcam video, like
> pulseaudio server for accessing more applications to microphone
> input.
> 

Because references are nice:

https://blogs.gnome.org/uraeus/2015/06/30/introducing-pulse-video/
https://gstconf.ubicast.tv/videos/camera-sharing-and-sandboxing-with-pinos/

And why the internals are not going to be implemented using GStreamer in the end:
https://gstconf.ubicast.tv/videos/keep-calm-and-refactor-about-the-essence-of-gstreamer/

regards,
Nicolas

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Re: support autofocus / autogain in libv4l2

[Nicolas Dufresne]

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Le mardi 25 avril 2017 à 10:05 +0200, Pavel Machek a écrit :
> Well, fd's are hard, because application can do fork() and now
> interesting stuff happens. Threads are tricky, because now you have
> locking etc.
> 
> libv4l2 is designed to be LD_PRELOADED. That is not really feasible
> with "complex" library.

That is incorrect. The library propose an API where you simply replace
certain low level calls, like ioctl -> v4l2_ioctl, open -> v4l2_open().
You have to do that explicitly in your existing code. It does not
abstract the API itself unlike libdrm.

Nicolas

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Re: support autofocus / autogain in libv4l2

[Pavel Machek]

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On Tue 2017-04-25 12:53:27, Nicolas Dufresne wrote:
> Le mardi 25 avril 2017 à 10:05 +0200, Pavel Machek a écrit :
> > Well, fd's are hard, because application can do fork() and now
> > interesting stuff happens. Threads are tricky, because now you have
> > locking etc.
> > 
> > libv4l2 is designed to be LD_PRELOADED. That is not really feasible
> > with "complex" library.
> 
> That is incorrect. The library propose an API where you simply replace
> certain low level calls, like ioctl -> v4l2_ioctl, open -> v4l2_open().
> You have to do that explicitly in your existing code. It does not
> abstract the API itself unlike libdrm.

You are right, no LD_PRELOAD. But same API as kernel, which is really
limiting -- see my other mail.

									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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[patch] propagating controls in libv4l2 was Re: support autofocus / autogain in libv4l2

[Pavel Machek]

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Hi!

> > > IMO, the best place for autofocus is at libv4l2. Putting it on a
> > > separate "video server" application looks really weird for me.  
> > 
> > Well... let me see. libraries are quite limited -- it is hard to open
> > files, or use threads/have custom main loop. It may be useful to
> > switch resolutions -- do autofocus/autogain at lower resolution, then
> > switch to high one for taking picture. It would be good to have that
> > in "system" code, but I'm not at all sure libv4l2 design will allow
> > that.
> 
> I don't see why it would be hard to open files or have threads inside
> a library. There are several libraries that do that already, specially
> the ones designed to be used on multimidia apps.

Well, This is what the libv4l2 says:

   This file implements libv4l2, which offers v4l2_ prefixed versions
   of
      open/close/etc. The API is 100% the same as directly opening
   /dev/videoX
      using regular open/close/etc, the big difference is that format
   conversion
   
but if I open additional files in v4l2_open(), API is no longer the
same, as unix open() is defined to open just one file descriptor.

Now. There is autogain support in libv4lconvert, but it expects to use
same fd for camera and for the gain... which does not work with
subdevs.

Of course, opening subdevs by name like this is not really
acceptable. But can you suggest a method that is?

Thanks,
								Pavel

commit 4cf9d10ead014c0db25452e4bb9cd144632407c3
Author: Pavel <pavel@ucw.cz>
Date:   Wed Apr 26 11:38:04 2017 +0200

    Add subdevices.

diff --git a/lib/libv4l2/libv4l2-priv.h b/lib/libv4l2/libv4l2-priv.h
index 343db5e..a6bc48e 100644
--- a/lib/libv4l2/libv4l2-priv.h
+++ b/lib/libv4l2/libv4l2-priv.h
@@ -26,6 +26,7 @@
 #include "../libv4lconvert/libv4lsyscall-priv.h"
 
 #define V4L2_MAX_DEVICES 16
+#define V4L2_MAX_SUBDEVS 8
 /* Warning when making this larger the frame_queued and frame_mapped members of
    the v4l2_dev_info struct can no longer be a bitfield, so the code needs to
    be adjusted! */
@@ -104,6 +105,7 @@ struct v4l2_dev_info {
 	void *plugin_library;
 	void *dev_ops_priv;
 	const struct libv4l_dev_ops *dev_ops;
+        int subdev_fds[V4L2_MAX_SUBDEVS];
 };
 
 /* From v4l2-plugin.c */
diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
index 0ba0a88..edc9642 100644
--- a/lib/libv4l2/libv4l2.c
+++ b/lib/libv4l2/libv4l2.c
@@ -1,3 +1,4 @@
+/* -*- c-file-style: "linux" -*- */
 /*
 #             (C) 2008 Hans de Goede <hdegoede@redhat.com>
 
@@ -789,18 +790,25 @@ no_capture:
 
 	/* Note we always tell v4lconvert to optimize src fmt selection for
 	   our default fps, the only exception is the app explicitly selecting
-	   a fram erate using the S_PARM ioctl after a S_FMT */
+	   a frame rate using the S_PARM ioctl after a S_FMT */
 	if (devices[index].convert)
 		v4lconvert_set_fps(devices[index].convert, V4L2_DEFAULT_FPS);
 	v4l2_update_fps(index, &parm);
 
+	devices[index].subdev_fds[0] = SYS_OPEN("/dev/video_sensor", O_RDWR, 0);
+	devices[index].subdev_fds[1] = SYS_OPEN("/dev/video_focus", O_RDWR, 0);
+	devices[index].subdev_fds[2] = -1;
+
+	printf("Sensor: %d, focus: %d\n", devices[index].subdev_fds[0], 
+	       devices[index].subdev_fds[1]);
+
 	V4L2_LOG("open: %d\n", fd);
 
 	return fd;
 }
 
 /* Is this an fd for which we are emulating v4l1 ? */
-static int v4l2_get_index(int fd)
+int v4l2_get_index(int fd)
 {
 	int index;
 

commit 1d6a9ce121f53e8f2e38549eed597a3c3dea5233
Author: Pavel <pavel@ucw.cz>
Date:   Wed Apr 26 12:34:04 2017 +0200

    Enable ioctl propagation.

diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
index edc9642..6dab661 100644
--- a/lib/libv4l2/libv4l2.c
+++ b/lib/libv4l2/libv4l2.c
@@ -1064,6 +1064,23 @@ static int v4l2_s_fmt(int index, struct v4l2_format *dest_fmt)
 	return 0;
 }
 
+static int v4l2_propagate_ioctl(int index, unsigned long request, void *arg)
+{
+	int i = 0;
+	int result;
+	while (1) {
+		if (devices[index].subdev_fds[i] == -1)
+			return -1;
+		printf("g_ctrl failed, trying...\n");
+		result = SYS_IOCTL(devices[index].subdev_fds[i], request, arg);
+		printf("subdev %d result %d\n", i, result);
+		if (result == 0)
+			return 0;
+		i++;
+	}
+	return -1;
+}
+
 int v4l2_ioctl(int fd, unsigned long int request, ...)
 {
 	void *arg;
@@ -1193,14 +1210,20 @@ no_capture_request:
 	switch (request) {
 	case VIDIOC_QUERYCTRL:
 		result = v4lconvert_vidioc_queryctrl(devices[index].convert, arg);
+		if (result == -1)
+			result = v4l2_propagate_ioctl(index, request, arg);
 		break;
 
 	case VIDIOC_G_CTRL:
 		result = v4lconvert_vidioc_g_ctrl(devices[index].convert, arg);
+		if (result == -1)
+			result = v4l2_propagate_ioctl(index, request, arg);
 		break;
 
 	case VIDIOC_S_CTRL:
 		result = v4lconvert_vidioc_s_ctrl(devices[index].convert, arg);
+		if (result == -1)
+			result = v4l2_propagate_ioctl(index, request, arg);
 		break;
 
 	case VIDIOC_G_EXT_CTRLS:


-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [patch] propagating controls in libv4l2 was Re: support autofocus / autogain in libv4l2

[Mauro Carvalho Chehab]

Hi Pavel,

Em Wed, 26 Apr 2017 12:53:00 +0200
Pavel Machek <pavel@ucw.cz> escreveu:

> Hi!
> 
> > > > IMO, the best place for autofocus is at libv4l2. Putting it on a
> > > > separate "video server" application looks really weird for me.    
> > > 
> > > Well... let me see. libraries are quite limited -- it is hard to open
> > > files, or use threads/have custom main loop. It may be useful to
> > > switch resolutions -- do autofocus/autogain at lower resolution, then
> > > switch to high one for taking picture. It would be good to have that
> > > in "system" code, but I'm not at all sure libv4l2 design will allow
> > > that.  
> > 
> > I don't see why it would be hard to open files or have threads inside
> > a library. There are several libraries that do that already, specially
> > the ones designed to be used on multimidia apps.  
> 
> Well, This is what the libv4l2 says:
> 
>    This file implements libv4l2, which offers v4l2_ prefixed versions
>    of
>       open/close/etc. The API is 100% the same as directly opening
>    /dev/videoX
>       using regular open/close/etc, the big difference is that format
>    conversion
>    
> but if I open additional files in v4l2_open(), API is no longer the
> same, as unix open() is defined to open just one file descriptor.
> 
> Now. There is autogain support in libv4lconvert, but it expects to use
> same fd for camera and for the gain... which does not work with
> subdevs.
> 
> Of course, opening subdevs by name like this is not really
> acceptable. But can you suggest a method that is?

There are two separate things here:

1) Autofoucs for a device that doesn't use subdev API
2) libv4l2 support for devices that require MC and subdev API

for (1), it should use the /dev/videoX device that was opened with
v4l2_open().

For (2), libv4l2 should be aware of MC and subdev APIs. Sakari
once tried to write a libv4l2 plugin for OMAP3, but never finished it.
A more recent trial were to add a libv4l2 plugin for Exynos.
Unfortunately, none of those code got merged. Last time I checked,
the Exynos plugin was almost ready to be merged, but Sakari asked
some changes on it. The developer that was working on it got job on
some other company. Last time I heard from him, he was still interested
on finishing his work, but in the need to setup a test environment
using his own devices.

So, currently, there's no code at all adding MC/subdev API
support merged at libv4l2.

-

IMHO, the right thing to do with regards to autofocus is to
implement it via a processing module, assuming that just one
video device is opened.

Then, add a N900 plugin to make libv4l2 aware of OMAP3 specifics.

After that, rework at the processing module to let it use a 
different file descriptor if such plugin is in usage.

-

The hole idea is that a libv4l2 client, running on a N900 device
would just open a fake /dev/video0. Internally, libv4l2 will
open whatever video nodes it needs to control the device, exporting
all hardware capabilities (video formats, controls, resolutions,
etc) as if it was a normal V4L2 camera, hiding all dirty details
about MC and subdev APIs from userspace application.

This way, a normal application, like xawtv, tvtime, camorama,
zbar, mplayer, vlc, ... will work without any changes.


> 
> Thanks,
> 								Pavel
> 
> commit 4cf9d10ead014c0db25452e4bb9cd144632407c3
> Author: Pavel <pavel@ucw.cz>
> Date:   Wed Apr 26 11:38:04 2017 +0200
> 
>     Add subdevices.
> 
> diff --git a/lib/libv4l2/libv4l2-priv.h b/lib/libv4l2/libv4l2-priv.h
> index 343db5e..a6bc48e 100644
> --- a/lib/libv4l2/libv4l2-priv.h
> +++ b/lib/libv4l2/libv4l2-priv.h
> @@ -26,6 +26,7 @@
>  #include "../libv4lconvert/libv4lsyscall-priv.h"
>  
>  #define V4L2_MAX_DEVICES 16
> +#define V4L2_MAX_SUBDEVS 8
>  /* Warning when making this larger the frame_queued and frame_mapped members of
>     the v4l2_dev_info struct can no longer be a bitfield, so the code needs to
>     be adjusted! */
> @@ -104,6 +105,7 @@ struct v4l2_dev_info {
>  	void *plugin_library;
>  	void *dev_ops_priv;
>  	const struct libv4l_dev_ops *dev_ops;
> +        int subdev_fds[V4L2_MAX_SUBDEVS];
>  };
>  
>  /* From v4l2-plugin.c */
> diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
> index 0ba0a88..edc9642 100644
> --- a/lib/libv4l2/libv4l2.c
> +++ b/lib/libv4l2/libv4l2.c
> @@ -1,3 +1,4 @@
> +/* -*- c-file-style: "linux" -*- */
>  /*
>  #             (C) 2008 Hans de Goede <hdegoede@redhat.com>
>  
> @@ -789,18 +790,25 @@ no_capture:
>  
>  	/* Note we always tell v4lconvert to optimize src fmt selection for
>  	   our default fps, the only exception is the app explicitly selecting
> -	   a fram erate using the S_PARM ioctl after a S_FMT */
> +	   a frame rate using the S_PARM ioctl after a S_FMT */
>  	if (devices[index].convert)
>  		v4lconvert_set_fps(devices[index].convert, V4L2_DEFAULT_FPS);
>  	v4l2_update_fps(index, &parm);
>  
> +	devices[index].subdev_fds[0] = SYS_OPEN("/dev/video_sensor", O_RDWR, 0);
> +	devices[index].subdev_fds[1] = SYS_OPEN("/dev/video_focus", O_RDWR, 0);
> +	devices[index].subdev_fds[2] = -1;
> +
> +	printf("Sensor: %d, focus: %d\n", devices[index].subdev_fds[0], 
> +	       devices[index].subdev_fds[1]);
> +
>  	V4L2_LOG("open: %d\n", fd);
>  
>  	return fd;
>  }
>  
>  /* Is this an fd for which we are emulating v4l1 ? */
> -static int v4l2_get_index(int fd)
> +int v4l2_get_index(int fd)
>  {
>  	int index;
>  
> 
> commit 1d6a9ce121f53e8f2e38549eed597a3c3dea5233
> Author: Pavel <pavel@ucw.cz>
> Date:   Wed Apr 26 12:34:04 2017 +0200
> 
>     Enable ioctl propagation.
> 
> diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
> index edc9642..6dab661 100644
> --- a/lib/libv4l2/libv4l2.c
> +++ b/lib/libv4l2/libv4l2.c
> @@ -1064,6 +1064,23 @@ static int v4l2_s_fmt(int index, struct v4l2_format *dest_fmt)
>  	return 0;
>  }
>  
> +static int v4l2_propagate_ioctl(int index, unsigned long request, void *arg)
> +{
> +	int i = 0;
> +	int result;
> +	while (1) {
> +		if (devices[index].subdev_fds[i] == -1)
> +			return -1;
> +		printf("g_ctrl failed, trying...\n");
> +		result = SYS_IOCTL(devices[index].subdev_fds[i], request, arg);
> +		printf("subdev %d result %d\n", i, result);
> +		if (result == 0)
> +			return 0;
> +		i++;
> +	}
> +	return -1;
> +}
> +
>  int v4l2_ioctl(int fd, unsigned long int request, ...)
>  {
>  	void *arg;
> @@ -1193,14 +1210,20 @@ no_capture_request:
>  	switch (request) {
>  	case VIDIOC_QUERYCTRL:
>  		result = v4lconvert_vidioc_queryctrl(devices[index].convert, arg);
> +		if (result == -1)
> +			result = v4l2_propagate_ioctl(index, request, arg);
>  		break;
>  
>  	case VIDIOC_G_CTRL:
>  		result = v4lconvert_vidioc_g_ctrl(devices[index].convert, arg);
> +		if (result == -1)
> +			result = v4l2_propagate_ioctl(index, request, arg);
>  		break;
>  
>  	case VIDIOC_S_CTRL:
>  		result = v4lconvert_vidioc_s_ctrl(devices[index].convert, arg);
> +		if (result == -1)
> +			result = v4l2_propagate_ioctl(index, request, arg);
>  		break;
>  
>  	case VIDIOC_G_EXT_CTRLS:
> 
> 



Thanks,
Mauro

[patch] autogain support for bayer10 format (was Re: [patch] propagating controls in libv4l2)

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 4705 bytes --]

Hi!

> > > I don't see why it would be hard to open files or have threads inside
> > > a library. There are several libraries that do that already, specially
> > > the ones designed to be used on multimidia apps.  
> > 
> > Well, This is what the libv4l2 says:
> > 
> >    This file implements libv4l2, which offers v4l2_ prefixed versions
> >    of
> >       open/close/etc. The API is 100% the same as directly opening
> >    /dev/videoX
> >       using regular open/close/etc, the big difference is that format
> >    conversion
> >    
> > but if I open additional files in v4l2_open(), API is no longer the
> > same, as unix open() is defined to open just one file descriptor.
> > 
> > Now. There is autogain support in libv4lconvert, but it expects to use
> > same fd for camera and for the gain... which does not work with
> > subdevs.
> > 
> > Of course, opening subdevs by name like this is not really
> > acceptable. But can you suggest a method that is?
> 
> There are two separate things here:
> 
> 1) Autofoucs for a device that doesn't use subdev API
> 2) libv4l2 support for devices that require MC and subdev API

Actually there are three: 0) autogain. Unfortunately, I need autogain
first before autofocus has a chance...

And that means... bayer10 support for autogain.

Plus, I changed avg_lum to long long. Quick calculation tells me int
could overflow with few megapixel sensor.

Oh, btw http://ytse.tricolour.net/docs/LowLightOptimization.html no
longer works.

Regards,
								Pavel

diff --git a/lib/libv4lconvert/processing/autogain.c b/lib/libv4lconvert/processing/autogain.c
index c6866d6..0b52d0f 100644
--- a/lib/libv4lconvert/processing/autogain.c
+++ b/lib/libv4lconvert/processing/autogain.c
@@ -68,6 +71,41 @@ static void autogain_adjust(struct v4l2_queryctrl *ctrl, int *value,
 	}
 }
 
+static int get_luminosity_bayer10(uint16_t *buf, const struct v4l2_format *fmt)
+{
+	long long avg_lum = 0;
+	int x, y;
+	
+	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
+		fmt->fmt.pix.width / 4;
+
+	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
+		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
+			avg_lum += *buf++;
+		buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
+	}
+	avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
+	avg_lum /= 4;
+	return avg_lum;
+}
+
+static int get_luminosity_bayer8(unsigned char *buf, const struct v4l2_format *fmt)
+{
+	long long avg_lum = 0;
+	int x, y;
+	
+	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
+		fmt->fmt.pix.width / 4;
+
+	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
+		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
+			avg_lum += *buf++;
+		buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
+	}
+	avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
+	return avg_lum;
+}
+
 /* auto gain and exposure algorithm based on the knee algorithm described here:
 http://ytse.tricolour.net/docs/LowLightOptimization.html */
 static int autogain_calculate_lookup_tables(
@@ -100,17 +142,16 @@ static int autogain_calculate_lookup_tables(
 	switch (fmt->fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGBRG10:
+	case V4L2_PIX_FMT_SGRBG10:
+	case V4L2_PIX_FMT_SBGGR10:
+	case V4L2_PIX_FMT_SRGGB10:
+		avg_lum = get_luminosity_bayer10((void *) buf, fmt);
+		break;
+
 	case V4L2_PIX_FMT_SGBRG8:
 	case V4L2_PIX_FMT_SGRBG8:
 	case V4L2_PIX_FMT_SBGGR8:
 	case V4L2_PIX_FMT_SRGGB8:
-		buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
-			fmt->fmt.pix.width / 4;
-
-		for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
-			for (x = 0; x < fmt->fmt.pix.width / 2; x++)
-				avg_lum += *buf++;
-			buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
-		}
-		avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
+		avg_lum = get_luminosity_bayer8(buf, fmt);
 		break;
 
 	case V4L2_PIX_FMT_RGB24:
diff --git a/lib/libv4lconvert/processing/libv4lprocessing.c b/lib/libv4lconvert/processing/libv4lprocessing.c
index b061f50..b98d024 100644
--- a/lib/libv4lconvert/processing/libv4lprocessing.c
+++ b/lib/libv4lconvert/processing/libv4lprocessing.c
@@ -164,6 +165,10 @@ void v4lprocessing_processing(struct v4lprocessing_data *data,
 	case V4L2_PIX_FMT_SGRBG8:
 	case V4L2_PIX_FMT_SBGGR8:
 	case V4L2_PIX_FMT_SRGGB8:
+	case V4L2_PIX_FMT_SGBRG10:
+	case V4L2_PIX_FMT_SGRBG10:
+	case V4L2_PIX_FMT_SBGGR10:
+	case V4L2_PIX_FMT_SRGGB10:
 	case V4L2_PIX_FMT_RGB24:
 	case V4L2_PIX_FMT_BGR24:
 		break;



-- 
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Re: [patch] autogain support for bayer10 format (was Re: [patch] propagating controls in libv4l2)

[Ivaylo Dimitrov]

Hi,

On 26.04.2017 16:23, Pavel Machek wrote:
> Hi!
>
>>>> I don't see why it would be hard to open files or have threads inside
>>>> a library. There are several libraries that do that already, specially
>>>> the ones designed to be used on multimidia apps.
>>>
>>> Well, This is what the libv4l2 says:
>>>
>>>    This file implements libv4l2, which offers v4l2_ prefixed versions
>>>    of
>>>       open/close/etc. The API is 100% the same as directly opening
>>>    /dev/videoX
>>>       using regular open/close/etc, the big difference is that format
>>>    conversion
>>>
>>> but if I open additional files in v4l2_open(), API is no longer the
>>> same, as unix open() is defined to open just one file descriptor.
>>>
>>> Now. There is autogain support in libv4lconvert, but it expects to use
>>> same fd for camera and for the gain... which does not work with
>>> subdevs.
>>>
>>> Of course, opening subdevs by name like this is not really
>>> acceptable. But can you suggest a method that is?
>>
>> There are two separate things here:
>>
>> 1) Autofoucs for a device that doesn't use subdev API
>> 2) libv4l2 support for devices that require MC and subdev API
>
> Actually there are three: 0) autogain. Unfortunately, I need autogain
> first before autofocus has a chance...
>
> And that means... bayer10 support for autogain.
>
> Plus, I changed avg_lum to long long. Quick calculation tells me int
> could overflow with few megapixel sensor.
>
> Oh, btw http://ytse.tricolour.net/docs/LowLightOptimization.html no
> longer works.
>
> Regards,
> 								Pavel
>
> diff --git a/lib/libv4lconvert/processing/autogain.c b/lib/libv4lconvert/processing/autogain.c
> index c6866d6..0b52d0f 100644
> --- a/lib/libv4lconvert/processing/autogain.c
> +++ b/lib/libv4lconvert/processing/autogain.c
> @@ -68,6 +71,41 @@ static void autogain_adjust(struct v4l2_queryctrl *ctrl, int *value,
>  	}
>  }
>
> +static int get_luminosity_bayer10(uint16_t *buf, const struct v4l2_format *fmt)
> +{
> +	long long avg_lum = 0;
> +	int x, y;
> +	
> +	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
> +		fmt->fmt.pix.width / 4;
> +
> +	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
> +		for (x = 0; x < fmt->fmt.pix.width / 2; x++)

That would take some time :). AIUI, we have NEON support in ARM kernels 
(CONFIG_KERNEL_MODE_NEON), I wonder if it makes sense (me) to convert 
the above loop to NEON-optimized when it comes to it? Are there any 
drawbacks in using NEON code in kernel?

> +			avg_lum += *buf++;
> +		buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
> +	}
> +	avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
> +	avg_lum /= 4;
> +	return avg_lum;
> +}
> +
> +static int get_luminosity_bayer8(unsigned char *buf, const struct v4l2_format *fmt)
> +{
> +	long long avg_lum = 0;
> +	int x, y;
> +	
> +	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
> +		fmt->fmt.pix.width / 4;
> +
> +	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
> +		for (x = 0; x < fmt->fmt.pix.width / 2; x++)

ditto.

> +			avg_lum += *buf++;
> +		buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
> +	}
> +	avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
> +	return avg_lum;
> +}
> +
>  /* auto gain and exposure algorithm based on the knee algorithm described here:
>  http://ytse.tricolour.net/docs/LowLightOptimization.html */
>  static int autogain_calculate_lookup_tables(
> @@ -100,17 +142,16 @@ static int autogain_calculate_lookup_tables(
>  	switch (fmt->fmt.pix.pixelformat) {
> +	case V4L2_PIX_FMT_SGBRG10:
> +	case V4L2_PIX_FMT_SGRBG10:
> +	case V4L2_PIX_FMT_SBGGR10:
> +	case V4L2_PIX_FMT_SRGGB10:
> +		avg_lum = get_luminosity_bayer10((void *) buf, fmt);
> +		break;
> +
>  	case V4L2_PIX_FMT_SGBRG8:
>  	case V4L2_PIX_FMT_SGRBG8:
>  	case V4L2_PIX_FMT_SBGGR8:
>  	case V4L2_PIX_FMT_SRGGB8:
> -		buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
> -			fmt->fmt.pix.width / 4;
> -
> -		for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
> -			for (x = 0; x < fmt->fmt.pix.width / 2; x++)
> -				avg_lum += *buf++;
> -			buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
> -		}
> -		avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
> +		avg_lum = get_luminosity_bayer8(buf, fmt);
>  		break;
>
>  	case V4L2_PIX_FMT_RGB24:
> diff --git a/lib/libv4lconvert/processing/libv4lprocessing.c b/lib/libv4lconvert/processing/libv4lprocessing.c
> index b061f50..b98d024 100644
> --- a/lib/libv4lconvert/processing/libv4lprocessing.c
> +++ b/lib/libv4lconvert/processing/libv4lprocessing.c
> @@ -164,6 +165,10 @@ void v4lprocessing_processing(struct v4lprocessing_data *data,
>  	case V4L2_PIX_FMT_SGRBG8:
>  	case V4L2_PIX_FMT_SBGGR8:
>  	case V4L2_PIX_FMT_SRGGB8:
> +	case V4L2_PIX_FMT_SGBRG10:
> +	case V4L2_PIX_FMT_SGRBG10:
> +	case V4L2_PIX_FMT_SBGGR10:
> +	case V4L2_PIX_FMT_SRGGB10:
>  	case V4L2_PIX_FMT_RGB24:
>  	case V4L2_PIX_FMT_BGR24:
>  		break;
>
>
>

Re: [patch] autogain support for bayer10 format (was Re: [patch] propagating controls in libv4l2)

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 2240 bytes --]

Hi!

> >>There are two separate things here:
> >>
> >>1) Autofoucs for a device that doesn't use subdev API
> >>2) libv4l2 support for devices that require MC and subdev API
> >
> >Actually there are three: 0) autogain. Unfortunately, I need autogain
> >first before autofocus has a chance...
> >
> >And that means... bayer10 support for autogain.
> >
> >Plus, I changed avg_lum to long long. Quick calculation tells me int
> >could overflow with few megapixel sensor.
> >
> >Oh, btw http://ytse.tricolour.net/docs/LowLightOptimization.html no
> >longer works.
> >
> >Regards,
> >								Pavel
> >
> >diff --git a/lib/libv4lconvert/processing/autogain.c b/lib/libv4lconvert/processing/autogain.c
> >index c6866d6..0b52d0f 100644
> >--- a/lib/libv4lconvert/processing/autogain.c
> >+++ b/lib/libv4lconvert/processing/autogain.c
> >@@ -68,6 +71,41 @@ static void autogain_adjust(struct v4l2_queryctrl *ctrl, int *value,
> > 	}
> > }
> >
> >+static int get_luminosity_bayer10(uint16_t *buf, const struct v4l2_format *fmt)
> >+{
> >+	long long avg_lum = 0;
> >+	int x, y;
> >+	
> >+	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
> >+		fmt->fmt.pix.width / 4;
> >+
> >+	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
> >+		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
> 
> That would take some time :). AIUI, we have NEON support in ARM kernels
> (CONFIG_KERNEL_MODE_NEON), I wonder if it makes sense (me) to convert the
> above loop to NEON-optimized when it comes to it? Are there any drawbacks in
> using NEON code in kernel?

Well, thanks for offer. This is actualy libv4l2.

But I'd say NEON conversion is not neccessary anytime soon. First,
this is just trying to get average luminosity. We can easily skip
quite a lot of pixels, and still get reasonable answer.

Second, omap3isp actually has a hardware block computing statistics
for us. We just don't use it for simplicity.

(But if you want to play with camera, I'll get you patches; there's
ton of work to be done, both kernel and userspace :-).

Regards,
								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [patch] autogain support for bayer10 format (was Re: [patch] propagating controls in libv4l2)

[Ivaylo Dimitrov]

On 27.04.2017 01:51, Pavel Machek wrote:
> Hi!
>
>>>> There are two separate things here:
>>>>
>>>> 1) Autofoucs for a device that doesn't use subdev API
>>>> 2) libv4l2 support for devices that require MC and subdev API
>>>
>>> Actually there are three: 0) autogain. Unfortunately, I need autogain
>>> first before autofocus has a chance...
>>>
>>> And that means... bayer10 support for autogain.
>>>
>>> Plus, I changed avg_lum to long long. Quick calculation tells me int
>>> could overflow with few megapixel sensor.
>>>
>>> Oh, btw http://ytse.tricolour.net/docs/LowLightOptimization.html no
>>> longer works.
>>>
>>> Regards,
>>> 								Pavel
>>>
>>> diff --git a/lib/libv4lconvert/processing/autogain.c b/lib/libv4lconvert/processing/autogain.c
>>> index c6866d6..0b52d0f 100644
>>> --- a/lib/libv4lconvert/processing/autogain.c
>>> +++ b/lib/libv4lconvert/processing/autogain.c
>>> @@ -68,6 +71,41 @@ static void autogain_adjust(struct v4l2_queryctrl *ctrl, int *value,
>>> 	}
>>> }
>>>
>>> +static int get_luminosity_bayer10(uint16_t *buf, const struct v4l2_format *fmt)
>>> +{
>>> +	long long avg_lum = 0;
>>> +	int x, y;
>>> +	
>>> +	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
>>> +		fmt->fmt.pix.width / 4;
>>> +
>>> +	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
>>> +		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
>>
>> That would take some time :). AIUI, we have NEON support in ARM kernels
>> (CONFIG_KERNEL_MODE_NEON), I wonder if it makes sense (me) to convert the
>> above loop to NEON-optimized when it comes to it? Are there any drawbacks in
>> using NEON code in kernel?
>
> Well, thanks for offer. This is actualy libv4l2.
>

Oh, somehow I got confused that this is kernel code :)

> But I'd say NEON conversion is not neccessary anytime soon. First,
> this is just trying to get average luminosity. We can easily skip
> quite a lot of pixels, and still get reasonable answer.
>
> Second, omap3isp actually has a hardware block computing statistics
> for us. We just don't use it for simplicity.
>

Right, I forgot about that.

> (But if you want to play with camera, I'll get you patches; there's
> ton of work to be done, both kernel and userspace :-).

Well, I saw a low hanging fruit I thought I can convert to NEON in a day 
or two, while having some rest from the huge "project" I am devoting all 
my spare time recently (rebasing hildon/maemo 5 on top of devuan 
Jessie). Still, if there is something relatively small to be done, just 
email me and I'll have a look.

Regards,
Ivo

Re: [patch] autogain support for bayer10 format (was Re: [patch] propagating controls in libv4l2)

[Pavel Machek]

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Hi!

> Oh, somehow I got confused that this is kernel code :)
> 
> >But I'd say NEON conversion is not neccessary anytime soon. First,
> >this is just trying to get average luminosity. We can easily skip
> >quite a lot of pixels, and still get reasonable answer.
> >
> >Second, omap3isp actually has a hardware block computing statistics
> >for us. We just don't use it for simplicity.
> >
> 
> Right, I forgot about that.
> 
> >(But if you want to play with camera, I'll get you patches; there's
> >ton of work to be done, both kernel and userspace :-).
> 
> Well, I saw a low hanging fruit I thought I can convert to NEON in a day or
> two, while having some rest from the huge "project" I am devoting all my
> spare time recently (rebasing hildon/maemo 5 on top of devuan Jessie).
> Still, if there is something relatively small to be done, just email me and
> I'll have a look.

Well, there's a ton of work on camera, and some work on
libcmtspeechdata. The later is rather self-contained.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [patch] autogain support for bayer10 format (was Re: [patch] propagating controls in libv4l2)

[Russell King - ARM Linux]

On Wed, Apr 26, 2017 at 06:43:54PM +0300, Ivaylo Dimitrov wrote:
> >+static int get_luminosity_bayer10(uint16_t *buf, const struct v4l2_format *fmt)
> >+{
> >+	long long avg_lum = 0;
> >+	int x, y;
> >+	
> >+	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
> >+		fmt->fmt.pix.width / 4;
> >+
> >+	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
> >+		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
> 
> That would take some time :). AIUI, we have NEON support in ARM kernels
> (CONFIG_KERNEL_MODE_NEON), I wonder if it makes sense (me) to convert the
> above loop to NEON-optimized when it comes to it? Are there any drawbacks in
> using NEON code in kernel?

Using neon without the VFP state saved and restored corrupts userspace's
FP state.  So, you have to save the entire VFP state to use neon in kernel
mode.  There are helper functions for this: kernel_neon_begin() and
kernel_neon_end().

You can't build C code with the compiler believing that neon is available
as the compiler could emit neon instructions in unprotected kernel code.

Note that kernel_neon_begin() is only allowed to be called outside
interrupt context and with preemption disabled.

Given that, do we really want to be walking over multi-megabytes of image
data in the kernel with preemption disabled - it sounds like a recipe for
a very sluggish system.  I think this should (and can only sensibly be
done) in userspace.

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according to speedtest.net.

Re: [patch] autogain support for bayer10 format (was Re: [patch] propagating controls in libv4l2)

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 1532 bytes --]

On Wed 2017-05-03 20:05:56, Russell King - ARM Linux wrote:
> On Wed, Apr 26, 2017 at 06:43:54PM +0300, Ivaylo Dimitrov wrote:
> > >+static int get_luminosity_bayer10(uint16_t *buf, const struct v4l2_format *fmt)
> > >+{
> > >+	long long avg_lum = 0;
> > >+	int x, y;
> > >+	
> > >+	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
> > >+		fmt->fmt.pix.width / 4;
> > >+
> > >+	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
> > >+		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
> > 
> > That would take some time :). AIUI, we have NEON support in ARM kernels
> > (CONFIG_KERNEL_MODE_NEON), I wonder if it makes sense (me) to convert the
> > above loop to NEON-optimized when it comes to it? Are there any drawbacks in
> > using NEON code in kernel?
> 
> Using neon without the VFP state saved and restored corrupts userspace's
> FP state.  So, you have to save the entire VFP state to use neon in kernel
> mode.  There are helper functions for this: kernel_neon_begin() and
> kernel_neon_end().
...
> Given that, do we really want to be walking over multi-megabytes of image
> data in the kernel with preemption disabled - it sounds like a recipe for
> a very sluggish system.  I think this should (and can only sensibly be
> done) in userspace.

The patch was for libv4l2. (And I explained why we don't need to
overoptimize this.)
									Pavel

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Re: [patch] autogain support for bayer10 format (was Re: [patch] propagating controls in libv4l2)

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 5135 bytes --]

On Wed 2017-04-26 15:23:37, Pavel Machek wrote:
> Hi!
> 
> > > > I don't see why it would be hard to open files or have threads inside
> > > > a library. There are several libraries that do that already, specially
> > > > the ones designed to be used on multimidia apps.  
> > > 
> > > Well, This is what the libv4l2 says:
> > > 
> > >    This file implements libv4l2, which offers v4l2_ prefixed versions
> > >    of
> > >       open/close/etc. The API is 100% the same as directly opening
> > >    /dev/videoX
> > >       using regular open/close/etc, the big difference is that format
> > >    conversion
> > >    
> > > but if I open additional files in v4l2_open(), API is no longer the
> > > same, as unix open() is defined to open just one file descriptor.
> > > 
> > > Now. There is autogain support in libv4lconvert, but it expects to use
> > > same fd for camera and for the gain... which does not work with
> > > subdevs.
> > > 
> > > Of course, opening subdevs by name like this is not really
> > > acceptable. But can you suggest a method that is?
> > 
> > There are two separate things here:
> > 
> > 1) Autofoucs for a device that doesn't use subdev API
> > 2) libv4l2 support for devices that require MC and subdev API
> 
> Actually there are three: 0) autogain. Unfortunately, I need autogain
> first before autofocus has a chance...
> 
> And that means... bayer10 support for autogain.
> 
> Plus, I changed avg_lum to long long. Quick calculation tells me int
> could overflow with few megapixel sensor.
> 
> Oh, btw http://ytse.tricolour.net/docs/LowLightOptimization.html no
> longer works.

Can I get some comments here? Patch will need fixup (constants need
adjusting), but is style/design acceptable?

Thanks,
								Pavel

> diff --git a/lib/libv4lconvert/processing/autogain.c b/lib/libv4lconvert/processing/autogain.c
> index c6866d6..0b52d0f 100644
> --- a/lib/libv4lconvert/processing/autogain.c
> +++ b/lib/libv4lconvert/processing/autogain.c
> @@ -68,6 +71,41 @@ static void autogain_adjust(struct v4l2_queryctrl *ctrl, int *value,
>  	}
>  }
>  
> +static int get_luminosity_bayer10(uint16_t *buf, const struct v4l2_format *fmt)
> +{
> +	long long avg_lum = 0;
> +	int x, y;
> +	
> +	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
> +		fmt->fmt.pix.width / 4;
> +
> +	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
> +		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
> +			avg_lum += *buf++;
> +		buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
> +	}
> +	avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
> +	avg_lum /= 4;
> +	return avg_lum;
> +}
> +
> +static int get_luminosity_bayer8(unsigned char *buf, const struct v4l2_format *fmt)
> +{
> +	long long avg_lum = 0;
> +	int x, y;
> +	
> +	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
> +		fmt->fmt.pix.width / 4;
> +
> +	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
> +		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
> +			avg_lum += *buf++;
> +		buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
> +	}
> +	avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
> +	return avg_lum;
> +}
> +
>  /* auto gain and exposure algorithm based on the knee algorithm described here:
>  http://ytse.tricolour.net/docs/LowLightOptimization.html */
>  static int autogain_calculate_lookup_tables(
> @@ -100,17 +142,16 @@ static int autogain_calculate_lookup_tables(
>  	switch (fmt->fmt.pix.pixelformat) {
> +	case V4L2_PIX_FMT_SGBRG10:
> +	case V4L2_PIX_FMT_SGRBG10:
> +	case V4L2_PIX_FMT_SBGGR10:
> +	case V4L2_PIX_FMT_SRGGB10:
> +		avg_lum = get_luminosity_bayer10((void *) buf, fmt);
> +		break;
> +
>  	case V4L2_PIX_FMT_SGBRG8:
>  	case V4L2_PIX_FMT_SGRBG8:
>  	case V4L2_PIX_FMT_SBGGR8:
>  	case V4L2_PIX_FMT_SRGGB8:
> -		buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
> -			fmt->fmt.pix.width / 4;
> -
> -		for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
> -			for (x = 0; x < fmt->fmt.pix.width / 2; x++)
> -				avg_lum += *buf++;
> -			buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
> -		}
> -		avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
> +		avg_lum = get_luminosity_bayer8(buf, fmt);
>  		break;
>  
>  	case V4L2_PIX_FMT_RGB24:
> diff --git a/lib/libv4lconvert/processing/libv4lprocessing.c b/lib/libv4lconvert/processing/libv4lprocessing.c
> index b061f50..b98d024 100644
> --- a/lib/libv4lconvert/processing/libv4lprocessing.c
> +++ b/lib/libv4lconvert/processing/libv4lprocessing.c
> @@ -164,6 +165,10 @@ void v4lprocessing_processing(struct v4lprocessing_data *data,
>  	case V4L2_PIX_FMT_SGRBG8:
>  	case V4L2_PIX_FMT_SBGGR8:
>  	case V4L2_PIX_FMT_SRGGB8:
> +	case V4L2_PIX_FMT_SGBRG10:
> +	case V4L2_PIX_FMT_SGRBG10:
> +	case V4L2_PIX_FMT_SBGGR10:
> +	case V4L2_PIX_FMT_SRGGB10:
>  	case V4L2_PIX_FMT_RGB24:
>  	case V4L2_PIX_FMT_BGR24:
>  		break;
> 
> 
> 



-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [patch] propagating controls in libv4l2 was Re: support autofocus / autogain in libv4l2

[Pavel Machek]

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Hi!

> > Now. There is autogain support in libv4lconvert, but it expects to use
> > same fd for camera and for the gain... which does not work with
> > subdevs.
> > 
> > Of course, opening subdevs by name like this is not really
> > acceptable. But can you suggest a method that is?
> 
> There are two separate things here:
> 
> 1) Autofoucs for a device that doesn't use subdev API
> 2) libv4l2 support for devices that require MC and subdev API
> 
> for (1), it should use the /dev/videoX device that was opened with
> v4l2_open().
> 
> For (2), libv4l2 should be aware of MC and subdev APIs. Sakari
> once tried to write a libv4l2 plugin for OMAP3, but never finished it.
> A more recent trial were to add a libv4l2 plugin for Exynos.
> Unfortunately, none of those code got merged. Last time I checked,
> the Exynos plugin was almost ready to be merged, but Sakari asked
> some changes on it. The developer that was working on it got job on
> some other company. Last time I heard from him, he was still interested
> on finishing his work, but in the need to setup a test environment
> using his own devices.

First... we should not have hardware-specific code in the
userspace. Hardware abstraction should be kernel's job.

Second... we really should solve "ioctl propagation" in
libv4l2. Because otherwise existing userspace is unusable in MC/subdev
drivers.

> IMHO, the right thing to do with regards to autofocus is to
> implement it via a processing module, assuming that just one
> video device is opened.

Ok, I have done that.

> The hole idea is that a libv4l2 client, running on a N900 device
> would just open a fake /dev/video0. Internally, libv4l2 will
> open whatever video nodes it needs to control the device, exporting
> all hardware capabilities (video formats, controls, resolutions,
> etc) as if it was a normal V4L2 camera, hiding all dirty details
> about MC and subdev APIs from userspace application.
> 
> This way, a normal application, like xawtv, tvtime, camorama,
> zbar, mplayer, vlc, ... will work without any changes.

Well, yes, we'd like to get there eventually. But we are not there at
the moment, and ioctl() propagation is one of the steps.

(I do have support specific for N900, but currently it is in python;
this is enough to make the camera usable.)

Regards,
								Pavel

								
> > diff --git a/lib/libv4l2/libv4l2-priv.h b/lib/libv4l2/libv4l2-priv.h
> > index 343db5e..a6bc48e 100644
> > --- a/lib/libv4l2/libv4l2-priv.h
> > +++ b/lib/libv4l2/libv4l2-priv.h
> > @@ -26,6 +26,7 @@
> >  #include "../libv4lconvert/libv4lsyscall-priv.h"
> >  
> >  #define V4L2_MAX_DEVICES 16
> > +#define V4L2_MAX_SUBDEVS 8
> >  /* Warning when making this larger the frame_queued and frame_mapped members of
> >     the v4l2_dev_info struct can no longer be a bitfield, so the code needs to
> >     be adjusted! */
> > @@ -104,6 +105,7 @@ struct v4l2_dev_info {
> >  	void *plugin_library;
> >  	void *dev_ops_priv;
> >  	const struct libv4l_dev_ops *dev_ops;
> > +        int subdev_fds[V4L2_MAX_SUBDEVS];
> >  };
> >  
> >  /* From v4l2-plugin.c */
> > diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
> > index 0ba0a88..edc9642 100644
> > --- a/lib/libv4l2/libv4l2.c
> > +++ b/lib/libv4l2/libv4l2.c
> > @@ -1,3 +1,4 @@
> > +/* -*- c-file-style: "linux" -*- */
> >  /*
> >  #             (C) 2008 Hans de Goede <hdegoede@redhat.com>
> >  
> > @@ -789,18 +790,25 @@ no_capture:
> >  
> >  	/* Note we always tell v4lconvert to optimize src fmt selection for
> >  	   our default fps, the only exception is the app explicitly selecting
> > -	   a fram erate using the S_PARM ioctl after a S_FMT */
> > +	   a frame rate using the S_PARM ioctl after a S_FMT */
> >  	if (devices[index].convert)
> >  		v4lconvert_set_fps(devices[index].convert, V4L2_DEFAULT_FPS);
> >  	v4l2_update_fps(index, &parm);
> >  
> > +	devices[index].subdev_fds[0] = SYS_OPEN("/dev/video_sensor", O_RDWR, 0);
> > +	devices[index].subdev_fds[1] = SYS_OPEN("/dev/video_focus", O_RDWR, 0);
> > +	devices[index].subdev_fds[2] = -1;
> > +
> > +	printf("Sensor: %d, focus: %d\n", devices[index].subdev_fds[0], 
> > +	       devices[index].subdev_fds[1]);
> > +
> >  	V4L2_LOG("open: %d\n", fd);
> >  
> >  	return fd;
> >  }
> >  
> >  /* Is this an fd for which we are emulating v4l1 ? */
> > -static int v4l2_get_index(int fd)
> > +int v4l2_get_index(int fd)
> >  {
> >  	int index;
> >  
> > 
> > commit 1d6a9ce121f53e8f2e38549eed597a3c3dea5233
> > Author: Pavel <pavel@ucw.cz>
> > Date:   Wed Apr 26 12:34:04 2017 +0200
> > 
> >     Enable ioctl propagation.
> > 
> > diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
> > index edc9642..6dab661 100644
> > --- a/lib/libv4l2/libv4l2.c
> > +++ b/lib/libv4l2/libv4l2.c
> > @@ -1064,6 +1064,23 @@ static int v4l2_s_fmt(int index, struct v4l2_format *dest_fmt)
> >  	return 0;
> >  }
> >  
> > +static int v4l2_propagate_ioctl(int index, unsigned long request, void *arg)
> > +{
> > +	int i = 0;
> > +	int result;
> > +	while (1) {
> > +		if (devices[index].subdev_fds[i] == -1)
> > +			return -1;
> > +		printf("g_ctrl failed, trying...\n");
> > +		result = SYS_IOCTL(devices[index].subdev_fds[i], request, arg);
> > +		printf("subdev %d result %d\n", i, result);
> > +		if (result == 0)
> > +			return 0;
> > +		i++;
> > +	}
> > +	return -1;
> > +}
> > +
> >  int v4l2_ioctl(int fd, unsigned long int request, ...)
> >  {
> >  	void *arg;
> > @@ -1193,14 +1210,20 @@ no_capture_request:
> >  	switch (request) {
> >  	case VIDIOC_QUERYCTRL:
> >  		result = v4lconvert_vidioc_queryctrl(devices[index].convert, arg);
> > +		if (result == -1)
> > +			result = v4l2_propagate_ioctl(index, request, arg);
> >  		break;
> >  
> >  	case VIDIOC_G_CTRL:
> >  		result = v4lconvert_vidioc_g_ctrl(devices[index].convert, arg);
> > +		if (result == -1)
> > +			result = v4l2_propagate_ioctl(index, request, arg);
> >  		break;
> >  
> >  	case VIDIOC_S_CTRL:
> >  		result = v4lconvert_vidioc_s_ctrl(devices[index].convert, arg);
> > +		if (result == -1)
> > +			result = v4l2_propagate_ioctl(index, request, arg);
> >  		break;
> >  
> >  	case VIDIOC_G_EXT_CTRLS:
> > 
> > 
> 
> 
> 
> Thanks,
> Mauro

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(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [patch] propagating controls in libv4l2 was Re: support autofocus / autogain in libv4l2

[Mauro Carvalho Chehab]

Em Wed, 26 Apr 2017 12:53:00 +0200
Pavel Machek <pavel@ucw.cz> escreveu:

> Hi!
> 
> > > > IMO, the best place for autofocus is at libv4l2. Putting it on a
> > > > separate "video server" application looks really weird for me.    
> > > 
> > > Well... let me see. libraries are quite limited -- it is hard to open
> > > files, or use threads/have custom main loop. It may be useful to
> > > switch resolutions -- do autofocus/autogain at lower resolution, then
> > > switch to high one for taking picture. It would be good to have that
> > > in "system" code, but I'm not at all sure libv4l2 design will allow
> > > that.  
> > 
> > I don't see why it would be hard to open files or have threads inside
> > a library. There are several libraries that do that already, specially
> > the ones designed to be used on multimidia apps.  
> 
> Well, This is what the libv4l2 says:
> 
>    This file implements libv4l2, which offers v4l2_ prefixed versions
>    of
>       open/close/etc. The API is 100% the same as directly opening
>    /dev/videoX
>       using regular open/close/etc, the big difference is that format
>    conversion
>    
> but if I open additional files in v4l2_open(), API is no longer the
> same, as unix open() is defined to open just one file descriptor.
> 
> Now. There is autogain support in libv4lconvert, but it expects to use
> same fd for camera and for the gain... which does not work with
> subdevs.
> 
> Of course, opening subdevs by name like this is not really
> acceptable. But can you suggest a method that is?
> 
> Thanks,
> 								Pavel
> 
> commit 4cf9d10ead014c0db25452e4bb9cd144632407c3
> Author: Pavel <pavel@ucw.cz>
> Date:   Wed Apr 26 11:38:04 2017 +0200
> 
>     Add subdevices.
> 
> diff --git a/lib/libv4l2/libv4l2-priv.h b/lib/libv4l2/libv4l2-priv.h
> index 343db5e..a6bc48e 100644
> --- a/lib/libv4l2/libv4l2-priv.h
> +++ b/lib/libv4l2/libv4l2-priv.h
> @@ -26,6 +26,7 @@
>  #include "../libv4lconvert/libv4lsyscall-priv.h"
>  
>  #define V4L2_MAX_DEVICES 16
> +#define V4L2_MAX_SUBDEVS 8

Isn't it a short number?

>  /* Warning when making this larger the frame_queued and frame_mapped members of
>     the v4l2_dev_info struct can no longer be a bitfield, so the code needs to
>     be adjusted! */
> @@ -104,6 +105,7 @@ struct v4l2_dev_info {
>  	void *plugin_library;
>  	void *dev_ops_priv;
>  	const struct libv4l_dev_ops *dev_ops;
> +        int subdev_fds[V4L2_MAX_SUBDEVS];
>  };
>  
>  /* From v4l2-plugin.c */
> diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
> index 0ba0a88..edc9642 100644
> --- a/lib/libv4l2/libv4l2.c
> +++ b/lib/libv4l2/libv4l2.c
> @@ -1,3 +1,4 @@
> +/* -*- c-file-style: "linux" -*- */

No emacs comments, please.

>  /*
>  #             (C) 2008 Hans de Goede <hdegoede@redhat.com>
>  
> @@ -789,18 +790,25 @@ no_capture:
>  
>  	/* Note we always tell v4lconvert to optimize src fmt selection for
>  	   our default fps, the only exception is the app explicitly selecting
> -	   a fram erate using the S_PARM ioctl after a S_FMT */
> +	   a frame rate using the S_PARM ioctl after a S_FMT */
>  	if (devices[index].convert)
>  		v4lconvert_set_fps(devices[index].convert, V4L2_DEFAULT_FPS);
>  	v4l2_update_fps(index, &parm);
>  
> +	devices[index].subdev_fds[0] = SYS_OPEN("/dev/video_sensor", O_RDWR, 0);
> +	devices[index].subdev_fds[1] = SYS_OPEN("/dev/video_focus", O_RDWR, 0);
> +	devices[index].subdev_fds[2] = -1;

Hardcoding names here is not a good idea. Ideally, it should open
the MC, using the newgen API, and parse the media graph.

The problem is that, even with newgen API, without the properties API
you likely won't be able to write a generic parser. So, we need a
plugin specific for OMAP3 (or at least some database that would teach
a generic plugin about OMAP3 specifics).

I guess that the approach that Jacek was taken were very close to what
a generic plugin would need:
	https://lwn.net/Articles/619449/

The last version of his patch set is here:
	https://patchwork.linuxtv.org/patch/37496/

I didn't review his patchset, but from what I saw, Sakari is the one
that found some issues on v7.1 patchset.

Sakari,

Could you shed us a light about why this patchset was not merged?

Are there anything really bad at the code, or just minor issues that
could be fixed later?

If it is the last case, perhaps we could merge the code, if this
would make easier for Pavel to work on a N9 solution using the
same approach.


Thanks,
Mauro

Re: [patch] propagating controls in libv4l2 was Re: support autofocus / autogain in libv4l2

[Pavel Machek]

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Hi!

> > +	devices[index].subdev_fds[0] = SYS_OPEN("/dev/video_sensor", O_RDWR, 0);
> > +	devices[index].subdev_fds[1] = SYS_OPEN("/dev/video_focus", O_RDWR, 0);
> > +	devices[index].subdev_fds[2] = -1;
> 
> Hardcoding names here is not a good idea. Ideally, it should open
> the MC, using the newgen API, and parse the media graph.
> 
> The problem is that, even with newgen API, without the properties API
> you likely won't be able to write a generic parser. So, we need a
> plugin specific for OMAP3 (or at least some database that would teach
> a generic plugin about OMAP3 specifics).
> 
> I guess that the approach that Jacek was taken were very close to what
> a generic plugin would need:
> 	https://lwn.net/Articles/619449/
> 
> The last version of his patch set is here:
> 	https://patchwork.linuxtv.org/patch/37496/
> 
> I didn't review his patchset, but from what I saw, Sakari is the one
> that found some issues on v7.1 patchset.
> 
> Sakari,
> 
> Could you shed us a light about why this patchset was not merged?
> 
> Are there anything really bad at the code, or just minor issues that
> could be fixed later?
> 
> If it is the last case, perhaps we could merge the code, if this
> would make easier for Pavel to work on a N9 solution using the
> same approach.

It would be nice to get some solution here. Camera without libv4l
support is pretty much useless :-(.

									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Camera support, Prague next week, sdlcam

[Pavel Machek]

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Hi!

I'd still like to get some reasonable support for cellphone camera in
Linux.

IMO first reasonable step is to merge sdlcam, then we can implement
autofocus, improve autogain... and rest of the boring stuff. Ouch and
media graph support would be nice. Currently, _nothing_ works with
media graph device, such as N900.

I'll talk about the issues at ELCE in few days:

https://osseu17.sched.com/event/ByYH/cheap-complex-cameras-pavel-machek-denx-software-engineering-gmbh

Will someone else be there? Is there some place where v4l people meet?

Best regards,

								Pavel

commit 8db1546cd0b5229ad7bf2605fd5c295365df57f8
Author: Pavel <pavel@ucw.cz>
Date:   Fri Oct 13 21:24:16 2017 +0200

    Port changes from "cleaner" branch. For some reason, SDL2_image is
    missing in compilation.
    
    gcc -std=gnu99 -I../.. -g -O2 -o sdlcam sdlcam-sdlcam.o  -ljpeg -lSDL2
    -lSDL2_image ../../lib/libv4l2/.libs/libv4l2.a ../../lib/libv4lconvert/.libs/libv4lconvert.a

diff --git a/configure.ac b/configure.ac
index f3691be..dc412c9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -98,6 +98,247 @@ LIBDVBV5_DOMAIN="libdvbv5"
 AC_DEFINE([LIBDVBV5_DOMAIN], "libdvbv5", [libdvbv5 domain])
 AC_SUBST(LIBDVBV5_DOMAIN)
 
+# Configure paths for SDL
+# Sam Lantinga 9/21/99
+# stolen from Manish Singh
+# stolen back from Frank Belew
+# stolen from Manish Singh
+# Shamelessly stolen from Owen Taylor
+#
+# Changelog:
+# * also look for SDL2.framework under Mac OS X
+
+# serial 1
+
+dnl AM_PATH_SDL2([MINIMUM-VERSION, [ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND]]])
+dnl Test for SDL, and define SDL_CFLAGS and SDL_LIBS
+dnl
+AC_DEFUN([AM_PATH_SDL2],
+[dnl 
+dnl Get the cflags and libraries from the sdl2-config script
+dnl
+AC_ARG_WITH(sdl-prefix,[  --with-sdl-prefix=PFX   Prefix where SDL is installed (optional)],
+            sdl_prefix="$withval", sdl_prefix="")
+AC_ARG_WITH(sdl-exec-prefix,[  --with-sdl-exec-prefix=PFX Exec prefix where SDL is installed (optional)],
+            sdl_exec_prefix="$withval", sdl_exec_prefix="")
+AC_ARG_ENABLE(sdltest, [  --disable-sdltest       Do not try to compile and run a test SDL program],
+		    , enable_sdltest=yes)
+AC_ARG_ENABLE(sdlframework, [  --disable-sdlframework Do not search for SDL2.framework],
+        , search_sdl_framework=yes)
+
+AC_ARG_VAR(SDL2_FRAMEWORK, [Path to SDL2.framework])
+
+  min_sdl_version=ifelse([$1], ,2.0.0,$1)
+
+  if test "x$sdl_prefix$sdl_exec_prefix" = x ; then
+    PKG_CHECK_MODULES([SDL], [sdl2 >= $min_sdl_version],
+           [sdl_pc=yes],
+           [sdl_pc=no])
+  else
+    sdl_pc=no
+    if test x$sdl_exec_prefix != x ; then
+      sdl_config_args="$sdl_config_args --exec-prefix=$sdl_exec_prefix"
+      if test x${SDL2_CONFIG+set} != xset ; then
+        SDL2_CONFIG=$sdl_exec_prefix/bin/sdl2-config
+      fi
+    fi
+    if test x$sdl_prefix != x ; then
+      sdl_config_args="$sdl_config_args --prefix=$sdl_prefix"
+      if test x${SDL2_CONFIG+set} != xset ; then
+        SDL2_CONFIG=$sdl_prefix/bin/sdl2-config
+      fi
+    fi
+  fi
+
+  if test "x$sdl_pc" = xyes ; then
+    no_sdl=""
+    SDL2_CONFIG="pkg-config sdl2"
+  else
+    as_save_PATH="$PATH"
+    if test "x$prefix" != xNONE && test "$cross_compiling" != yes; then
+      PATH="$prefix/bin:$prefix/usr/bin:$PATH"
+    fi
+    AC_PATH_PROG(SDL2_CONFIG, sdl2-config, no, [$PATH])
+    PATH="$as_save_PATH"
+    no_sdl=""
+
+    if test "$SDL2_CONFIG" = "no" -a "x$search_sdl_framework" = "xyes"; then
+      AC_MSG_CHECKING(for SDL2.framework)
+      if test "x$SDL2_FRAMEWORK" != x; then
+        sdl_framework=$SDL2_FRAMEWORK
+      else
+        for d in / ~/ /System/; do
+          if test -d "$dLibrary/Frameworks/SDL2.framework"; then
+            sdl_framework="$dLibrary/Frameworks/SDL2.framework"
+          fi
+        done
+      fi
+
+      if test -d $sdl_framework; then
+        AC_MSG_RESULT($sdl_framework)
+        sdl_framework_dir=`dirname $sdl_framework`
+        SDL_CFLAGS="-F$sdl_framework_dir -Wl,-framework,SDL2 -I$sdl_framework/include"
+        SDL_LIBS="-F$sdl_framework_dir -Wl,-framework,SDL2"
+      else
+        no_sdl=yes
+      fi
+    fi
+
+    if test "$SDL2_CONFIG" != "no"; then
+      if test "x$sdl_pc" = "xno"; then
+        AC_MSG_CHECKING(for SDL - version >= $min_sdl_version)
+        SDL_CFLAGS=`$SDL2_CONFIG $sdl_config_args --cflags`
+        SDL_LIBS=`$SDL2_CONFIG $sdl_config_args --libs`
+      fi
+
+      sdl_major_version=`$SDL2_CONFIG $sdl_config_args --version | \
+             sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\1/'`
+      sdl_minor_version=`$SDL2_CONFIG $sdl_config_args --version | \
+             sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\2/'`
+      sdl_micro_version=`$SDL2_CONFIG $sdl_config_args --version | \
+             sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\3/'`
+      if test "x$enable_sdltest" = "xyes" ; then
+        ac_save_CFLAGS="$CFLAGS"
+        ac_save_CXXFLAGS="$CXXFLAGS"
+        ac_save_LIBS="$LIBS"
+        CFLAGS="$CFLAGS $SDL_CFLAGS"
+        CXXFLAGS="$CXXFLAGS $SDL_CFLAGS"
+        LIBS="$LIBS $SDL_LIBS"
+dnl
+dnl Now check if the installed SDL is sufficiently new. (Also sanity
+dnl checks the results of sdl2-config to some extent
+dnl
+      rm -f conf.sdltest
+      AC_TRY_RUN([
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "SDL.h"
+
+char*
+my_strdup (char *str)
+{
+  char *new_str;
+  
+  if (str)
+    {
+      new_str = (char *)malloc ((strlen (str) + 1) * sizeof(char));
+      strcpy (new_str, str);
+    }
+  else
+    new_str = NULL;
+  
+  return new_str;
+}
+
+int main (int argc, char *argv[])
+{
+  int major, minor, micro;
+  char *tmp_version;
+
+  /* This hangs on some systems (?)
+  system ("touch conf.sdltest");
+  */
+  { FILE *fp = fopen("conf.sdltest", "a"); if ( fp ) fclose(fp); }
+
+  /* HP/UX 9 (%@#!) writes to sscanf strings */
+  tmp_version = my_strdup("$min_sdl_version");
+  if (sscanf(tmp_version, "%d.%d.%d", &major, &minor, &micro) != 3) {
+     printf("%s, bad version string\n", "$min_sdl_version");
+     exit(1);
+   }
+
+   if (($sdl_major_version > major) ||
+      (($sdl_major_version == major) && ($sdl_minor_version > minor)) ||
+      (($sdl_major_version == major) && ($sdl_minor_version == minor) && ($sdl_micro_version >= micro)))
+    {
+      return 0;
+    }
+  else
+    {
+      printf("\n*** 'sdl2-config --version' returned %d.%d.%d, but the minimum version\n", $sdl_major_version, $sdl_minor_version, $sdl_micro_version);
+      printf("*** of SDL required is %d.%d.%d. If sdl2-config is correct, then it is\n", major, minor, micro);
+      printf("*** best to upgrade to the required version.\n");
+      printf("*** If sdl2-config was wrong, set the environment variable SDL2_CONFIG\n");
+      printf("*** to point to the correct copy of sdl2-config, and remove the file\n");
+      printf("*** config.cache before re-running configure\n");
+      return 1;
+    }
+}
+
+],, no_sdl=yes,[echo $ac_n "cross compiling; assumed OK... $ac_c"])
+        CFLAGS="$ac_save_CFLAGS"
+        CXXFLAGS="$ac_save_CXXFLAGS"
+        LIBS="$ac_save_LIBS"
+
+      fi
+      if test "x$sdl_pc" = "xno"; then
+        if test "x$no_sdl" = "xyes"; then
+          AC_MSG_RESULT(no)
+        else
+          AC_MSG_RESULT(yes)
+        fi
+      fi
+    fi
+  fi
+  if test "x$no_sdl" = x ; then
+     ifelse([$2], , :, [$2])
+  else
+     if test "$SDL2_CONFIG" = "no" ; then
+       echo "*** The sdl2-config script installed by SDL could not be found"
+       echo "*** If SDL was installed in PREFIX, make sure PREFIX/bin is in"
+       echo "*** your path, or set the SDL2_CONFIG environment variable to the"
+       echo "*** full path to sdl2-config."
+     else
+       if test -f conf.sdltest ; then
+        :
+       else
+          echo "*** Could not run SDL test program, checking why..."
+          CFLAGS="$CFLAGS $SDL_CFLAGS"
+          CXXFLAGS="$CXXFLAGS $SDL_CFLAGS"
+          LIBS="$LIBS $SDL_LIBS"
+          AC_TRY_LINK([
+#include <stdio.h>
+#include "SDL.h"
+
+int main(int argc, char *argv[])
+{ return 0; }
+#undef  main
+#define main K_and_R_C_main
+],      [ return 0; ],
+        [ echo "*** The test program compiled, but did not run. This usually means"
+          echo "*** that the run-time linker is not finding SDL or finding the wrong"
+          echo "*** version of SDL. If it is not finding SDL, you'll need to set your"
+          echo "*** LD_LIBRARY_PATH environment variable, or edit /etc/ld.so.conf to point"
+          echo "*** to the installed location  Also, make sure you have run ldconfig if that"
+          echo "*** is required on your system"
+	  echo "***"
+          echo "*** If you have an old version installed, it is best to remove it, although"
+          echo "*** you may also be able to get things to work by modifying LD_LIBRARY_PATH"],
+        [ echo "*** The test program failed to compile or link. See the file config.log for the"
+          echo "*** exact error that occured. This usually means SDL was incorrectly installed"
+          echo "*** or that you have moved SDL since it was installed. In the latter case, you"
+          echo "*** may want to edit the sdl2-config script: $SDL2_CONFIG" ])
+          CFLAGS="$ac_save_CFLAGS"
+          CXXFLAGS="$ac_save_CXXFLAGS"
+          LIBS="$ac_save_LIBS"
+       fi
+     fi
+     SDL_CFLAGS=""
+     SDL_LIBS=""
+     ifelse([$3], , :, [$3])
+  fi
+  AC_SUBST(SDL_CFLAGS)
+  AC_SUBST(SDL_LIBS)
+  rm -f conf.sdltest
+])
+
+dnl Check for SDL
+SDL_VERSION=2.0
+AM_PATH_SDL2($SDL_VERSION, sdl_pkgconfig=yes, sdl_pkgconfig=no)
+
+AM_CONDITIONAL([HAVE_SDL], [test x$sdl_pkgconfig = xyes])
+
 # Define localedir
 AC_DEFUN([V4L_EXPAND_PREFIX], [
 	$1=$2
@@ -507,6 +748,7 @@ compile time options summary
     pthread                    : $have_pthread
     QT version                 : $QT_VERSION
     ALSA support               : $USE_ALSA
+    SDL support		       : $sdl_pkgconfig
 
     build dynamic libs         : $enable_shared
     build static libs          : $enable_static
diff --git a/contrib/test/Makefile.am b/contrib/test/Makefile.am
index 4641e21..4e585cf 100644
--- a/contrib/test/Makefile.am
+++ b/contrib/test/Makefile.am
@@ -16,6 +16,10 @@ if HAVE_GLU
 noinst_PROGRAMS += v4l2gl
 endif
 
+if HAVE_SDL
+noinst_PROGRAMS += sdlcam
+endif
+
 driver_test_SOURCES = driver-test.c
 driver_test_LDADD = ../../utils/libv4l2util/libv4l2util.la
 
@@ -31,6 +35,11 @@ v4l2gl_SOURCES = v4l2gl.c
 v4l2gl_LDFLAGS = $(X11_LIBS) $(GL_LIBS) $(GLU_LIBS) $(ARGP_LIBS)
 v4l2gl_LDADD = ../../lib/libv4l2/libv4l2.la ../../lib/libv4lconvert/libv4lconvert.la
 
+sdlcam_LDFLAGS = $(JPEG_LIBS) $(SDL_LIBS) ../../lib/libv4l2/.libs/libv4l2.a  ../../lib/libv4lconvert/.libs/libv4lconvert.a
+sdlcam_CFLAGS = -I../..
+v4l2gl_LDADD = 
+# ../../lib/libv4l2/libv4l2.la ../../lib/libv4lconvert/libv4lconvert.la
+
 mc_nextgen_test_CFLAGS = $(LIBUDEV_CFLAGS)
 mc_nextgen_test_LDFLAGS = $(LIBUDEV_LIBS)
 
diff --git a/contrib/test/libcam.c b/contrib/test/libcam.c
new file mode 100644
index 0000000..115e6b1
--- /dev/null
+++ b/contrib/test/libcam.c
@@ -0,0 +1,48 @@
+static void fmt_print(struct v4l2_format *fmt)
+{
+	int f;
+	printf("Format: %dx%d. ", fmt->fmt.pix.width, fmt->fmt.pix.height);
+	printf("%x ", fmt->fmt.pix.pixelformat);
+	f = fmt->fmt.pix.pixelformat;
+	for (int i=0; i<4; i++) {
+		printf("%c", f & 0xff);
+		f >>= 8;
+	}
+	printf("\n");
+}
+
+static void pgm_write(struct v4l2_format *fmt, unsigned char *img, char *out_name, char *extra)
+{
+	FILE *fout;
+	int size = fmt->fmt.pix.width * fmt->fmt.pix.height;
+	char swapped[size*2];
+
+	fout = fopen(out_name, "w");
+	if (!fout) {
+		perror("Cannot open image");
+		exit(EXIT_FAILURE);
+	}
+	switch (fmt->fmt.pix.pixelformat) {
+		/* ?? 	cinfo.in_color_space = JCS_YCbCr; */
+	case V4L2_PIX_FMT_SGRBG10:
+		printf("ok\n");
+		break;
+	default:
+		printf("Bad pixel format\n");
+		exit(1);
+	}
+
+	for (int i=0; i<size*2; i+=2) {
+		swapped[i] = img[i+1];
+		swapped[i+1] = img[i];
+	}
+
+	fprintf(fout, "P5\n");
+	if (extra)
+		fprintf(fout, "%s", extra);
+	  
+	fprintf(fout, "%d %d\n1023\n",
+		fmt->fmt.pix.width, fmt->fmt.pix.height);
+	fwrite(swapped, size, 2, fout);
+	fclose(fout);
+}
diff --git a/contrib/test/raw.c b/contrib/test/raw.c
new file mode 100644
index 0000000..70d3340
--- /dev/null
+++ b/contrib/test/raw.c
@@ -0,0 +1,298 @@
+/* -*- c-file-style: "linux" -*- */
+/*
+   lens-shading is described at page 1411 of omap3isp manual,
+   downsampled by 4..64
+
+   gcc -std=c99 raw.c
+*/
+
+#include <linux/videodev2.h>
+#include <arpa/inet.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "libcam.c"
+
+struct image {
+	struct v4l2_format fmt;
+	unsigned char *buf;
+	unsigned char data[]; 
+};
+
+struct image *read_pgm(char *name)
+{
+	FILE *f;
+	char buf[1024];
+	struct v4l2_format fmt;
+	int max;
+
+
+	f = fopen(name, "r");
+	if (!f) {
+		printf("Can not open: %s\n", name);
+		return NULL;
+	}
+	fgets(buf, sizeof(buf)-1, f);
+	if (strcmp(buf, "P5\n")) {
+		printf("Not a pgm\n");
+		return NULL;
+	}
+
+	fgets(buf, sizeof(buf)-1, f);
+	while (buf[0] == '#')
+		fgets(buf, sizeof(buf)-1, f);
+
+	fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	fmt.fmt.pix.field = V4L2_FIELD_NONE;
+
+	if (2 != sscanf(buf, "%d %d\n", &fmt.fmt.pix.width, &fmt.fmt.pix.height))
+		printf("Could not read size: %s\n", buf);
+	fgets(buf, sizeof(buf)-1, f);
+	if (1 != sscanf(buf, "%d\n", &max))
+		printf("Could not read bits\n");
+
+	int size = fmt.fmt.pix.width * fmt.fmt.pix.height;
+	int bpp;
+	switch (max) {
+	case 255:
+		bpp = 1;
+		fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_SGRBG8;		
+		break;
+	case 1023:
+		bpp = 2;
+		fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_SGRBG10;
+		break;
+	default:
+		printf("Unexpected image depth: %d\n", max);
+		return NULL;
+	}
+
+	struct image *img = malloc(sizeof(struct image) + size*bpp);
+	img->buf = img->data;
+	fmt_print(&fmt);
+
+	if (size != fread(img->buf, bpp, size, f))
+		printf("Short read, bpp %d\n", bpp);
+
+	if (bpp == 2)
+		for (int i = 0; i < size; i++) {
+			unsigned short *b = (void *) img->buf;
+			b[i] = ntohs(b[i]);
+		}
+
+	img->fmt = fmt;
+
+	fclose(f);
+	return img;
+}
+
+static inline int img_pos(struct image *img, int x, int y)
+{
+	return y*img->fmt.fmt.pix.width + x;
+}
+
+static inline unsigned short img_value(struct image *img, int x, int y)
+{
+	int pos = img_pos(img, x, y);
+
+	switch (img->fmt.fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGRBG8:
+		return img->buf[pos];
+	case  V4L2_PIX_FMT_SGRBG10:
+		return ((unsigned short *)img->buf)[pos];
+	default:
+		printf("Unknown format in img_value\n");
+		exit(1);
+	}
+}
+
+static int img_value_safe(struct image *img, int x, int y)
+{
+	if ((x < 0) || (y < 0))
+		return -1;
+	if ((x >= img->fmt.fmt.pix.width) || (y >= img->fmt.fmt.pix.height))
+		return -1;
+	return img_value(img, x, y);
+}
+
+static inline void img_value_set(struct image *img, int x, int y, int v)
+{
+	int pos = img_pos(img, x, y);
+
+	switch (img->fmt.fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGRBG8:
+		img->buf[pos] = v;
+		break;
+	case  V4L2_PIX_FMT_SGRBG10:
+		((unsigned short *)img->buf)[pos] = v;
+		break;
+	default:
+		printf("Unknown format in img_value_set\n");
+		exit(1);
+	}
+}
+
+static inline int img_max_value(struct image *img)
+{
+	switch (img->fmt.fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGRBG8:
+		return 255;
+	case  V4L2_PIX_FMT_SGRBG10:
+		return 1023;
+	default:
+		printf("Unknown format in img_value_max\n");
+		exit(1);
+	}
+}
+
+static int img_expected_value(struct image *img, int x, int y)
+{
+	int v = 0, n = 0, v1;
+
+	v1 = img_value_safe(img, x-2, y);
+	if (v1 >= 0)
+		v += v1, n++;
+
+	v1 = img_value_safe(img, x+2, y);
+	if (v1 >= 0)
+		v += v1, n++;
+
+	v1 = img_value_safe(img, x, y-2);
+	if (v1 >= 0)
+		v += v1, n++;
+
+	v1 = img_value_safe(img, x, y+2);
+	if (v1 >= 0)
+		v += v1, n++;
+
+	v /= n;
+	return v;
+}
+
+/* img -= sub */
+static void img_substract(struct image *img, struct image *sub)
+{
+	for (int y=0; y<img->fmt.fmt.pix.height; y++)
+		for (int x=0; x<img->fmt.fmt.pix.width; x++) {
+			int v = img_value(img, x, y) -
+				img_value(sub, x, y);
+			if (v < 0)
+				v = 0;
+			img_value_set(img, x, y, v);
+		}
+}
+
+static int histogram_perc(int *cdf, int buckets, int perc)
+{
+	long long total = cdf[buckets-1];	
+	int lim = total * perc / 10000;
+
+	for (int i=0; i<buckets; i++)
+		if (cdf[i] > lim)
+			return i;
+	return buckets-1;
+}
+
+static void img_histogram(struct image *img, int cdf[], int buckets, int step)
+{
+	int max = img_max_value(img);
+
+	for (int i=0; i<buckets; i++)
+		cdf[i] = 0;
+	
+	for (int y = 0; y < img->fmt.fmt.pix.height; y+=step)
+		for (int x = 0; x < img->fmt.fmt.pix.width; x+=step) {
+			int b;
+			b = img_value(img, x, y);
+			b = (b * buckets)/(max+1);
+			cdf[b]++;
+		}
+
+	for (int i=1; i<buckets; i++)
+		cdf[i] += cdf[i-1];
+}
+
+static void img_remove_dead(struct image *img, struct image *sub)
+{
+	int buckets = 1024;
+	int cdf[buckets];
+	int lim;
+	img_histogram(sub, cdf, buckets, 1);
+
+	printf("Total is %d\n", cdf[buckets-1]);
+	printf("Median is %d\n", histogram_perc(cdf, buckets, 5000));
+	lim = histogram_perc(cdf, buckets, 9999);
+	printf("99th percentile is %d (%d)\n", lim, lim/4);
+	lim = lim + lim / 10;
+	printf("bad pixel limit is %d (%d)\n", lim, lim/4);
+	printf("%d bad pixels\n", cdf[buckets-1] - cdf[lim]);
+
+	int c = 0;
+
+	for (int y = 0; y < img->fmt.fmt.pix.height; y++)
+		for (int x = 0; x < img->fmt.fmt.pix.width; x++) {
+			int v = img_value(sub, x, y);
+			if (v > lim) {
+				int vo = img_value(img, x, y);
+				int v1 = img_expected_value(img, x, y);
+
+				img_value_set(img, x, y, v1);
+				//printf("Bad pixel, dark: %d %d -> %d\n", v, vo, v1);
+				c++;
+			}
+		}
+	printf("Corrected %d bad pixels\n", c);
+
+}
+
+static void img_shading(struct image *img, struct image *cor)
+{
+	int syi = img->fmt.fmt.pix.height;
+	int syc = cor->fmt.fmt.pix.height;
+	int sxi = img->fmt.fmt.pix.width;
+	int sxc = cor->fmt.fmt.pix.width;
+	int max = 0, min = 255;
+	
+	for (int y=0; y<syc; y++)
+		for (int x=0; x<sxc; x++) {
+			int v = img_value(cor, x, y);
+
+			if (v < min)
+				min = v;
+			if (v > max)
+				max = v;
+		}
+
+	printf("Extremes in correction image are %d, %d\n", min, max);
+
+	int m = img_max_value(img);
+	for (int y=0; y<syi; y++) {
+		int yc = (y*syc) / syi;
+		for (int x=0; x<sxi; x++) {
+			int xc = (x*sxc) / sxi;
+			int v = img_value(img, x, y);
+			int vc = img_value(cor, xc, yc);
+
+			v = (v * max) / vc;
+			if (v > m)
+				v = m;
+			img_value_set(img, x, y, v);
+
+		}
+	}
+}
+
+int main(void)
+{
+	struct image *img = read_pgm("/data/tmp/test_dark.pgm");
+	struct image *dark = read_pgm("/data/tmp/dark_max_iso_exp.pgm");
+	struct image *shading = read_pgm("/data/tmp/lens_shading.pgm");
+
+	pgm_write(&img->fmt, img->buf, "/data/tmp/delme_original.pgm", NULL);
+	//img_substract(img, dark);
+	img_remove_dead(img, dark);
+	pgm_write(&img->fmt, img->buf, "/data/tmp/delme_dark.pgm", NULL);
+	img_shading(img, shading);
+	pgm_write(&img->fmt, img->buf, "/data/tmp/delme_shading.pgm", NULL);
+}
diff --git a/contrib/test/sdlcam.c b/contrib/test/sdlcam.c
new file mode 100644
index 0000000..69b9712
--- /dev/null
+++ b/contrib/test/sdlcam.c
@@ -0,0 +1,1385 @@
+/* -*- c-file-style: "linux" -*- */
+/* Digital still camera.
+
+   SDL based, suitable for camera phone such as Nokia N900. In
+   particular, we support focus, gain and exposure control, but not
+   aperture control or lens zoom.
+
+   Copyright 2017 Pavel Machek, LGPL
+
+*/
+
+#include <time.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+
+#include <jpeglib.h>
+
+#include "libv4l2.h"
+#include <linux/videodev2.h>
+#define COOKED
+#ifdef COOKED
+#include "../../lib/libv4l2/libv4l2-priv.h"
+#endif
+#include "libv4l-plugin.h"
+
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_image.h>
+
+#include "libcam.c"
+
+static double dtime(void)
+{
+	static double start = 0.0;
+	struct timeval now;
+
+	gettimeofday(&now, NULL);
+
+	double n = now.tv_sec + now.tv_usec / 1000000.;
+	if (!start)
+		start = n;
+	return n - start;
+}
+
+static long v4l2_g_ctrl(int fd, long id)
+{
+	int res;
+	struct v4l2_control ctrl;
+	ctrl.id = id;
+	res = v4l2_ioctl(fd, VIDIOC_G_CTRL, &ctrl);
+	if (res < 0)
+		printf("Get control %ld failed\n", id);
+	return ctrl.value;
+}
+
+static int v4l2_s_ctrl(int fd, long id, long value)
+{
+	int res;
+	struct v4l2_control ctrl;
+	ctrl.id = id;
+	ctrl.value = value;
+	res = v4l2_ioctl(fd, VIDIOC_S_CTRL, &ctrl);
+	if (res < 0)
+		printf("Set control %lx %ld failed\n", id, value);
+	return res;
+}
+
+
+static int v4l2_set_focus(int fd, int diopt)
+{
+	if (v4l2_s_ctrl(fd, V4L2_CID_FOCUS_ABSOLUTE, diopt) < 0) {
+		printf("Could not set focus\n");
+	}
+	return 0;
+}
+
+#define SX 2592
+#define SY 1968
+#define SIZE SX*SY*3
+struct dev_info {
+	int fd;
+	struct v4l2_format fmt;
+
+	unsigned char buf[SIZE];
+	int debug;
+#define D_TIMING 1
+};
+
+struct sdl {
+	SDL_Window *window;
+	SDL_Surface *screen, *liveview;
+
+	int wx, wy; /* Window size */
+	int sx, sy; /* Live view size */
+	int bx, by; /* Border size */
+	int nx, ny; /* Number of buttons */
+	float factor;
+
+	/* These should go separately */
+	int do_focus, do_exposure, do_flash, do_white, do_big, do_full;
+	double zoom;
+	double focus_min;
+
+	int slider_mode;
+#define M_BIAS 0
+#define M_EXPOSURE 1
+#define M_GAIN 2
+#define M_FOCUS 3
+#define M_NUM 4
+	
+	int fd;
+
+	struct dev_info *dev;
+};
+
+typedef struct {
+	uint8_t r, g, b, alpha;
+} pixel;
+
+#define d_raw 1
+
+static void sfc_put_pixel(SDL_Surface* liveview, int x, int y, pixel *p)
+{
+	Uint32* p_liveview = (Uint32*)liveview->pixels;
+	p_liveview += y*liveview->w+x;
+	*p_liveview = SDL_MapRGBA(liveview->format, p->r, p->g, p->b, p->alpha);
+}
+
+static void sdl_begin_paint(struct sdl *m)
+{
+	/* Fill the surface white */
+	SDL_FillRect(m->liveview, NULL, SDL_MapRGB( m->liveview->format, 0, 0, 0 ));
+
+	SDL_LockSurface(m->liveview);
+}
+
+static void sdl_finish_paint(struct sdl *m) {
+	SDL_UnlockSurface(m->liveview);
+	SDL_Rect rcDest = { m->bx, m->by, m->sx, m->sy };
+
+	SDL_BlitSurface(m->liveview, NULL, m->screen, &rcDest);
+	SDL_UpdateWindowSurfaceRects(m->window, &rcDest, 1);
+}
+  
+static void sdl_paint_image(struct sdl *m, char **xpm, int x, int y) {
+	SDL_Surface *image = IMG_ReadXPMFromArray(xpm);
+	if (!image) {
+		printf("IMG_Load: %s\n", IMG_GetError());
+		exit(1);
+	}
+
+	int x_pos = x - image->w/2, y_pos = y - image->h/2;
+
+	SDL_Rect rcDest = { x_pos, y_pos, image->w, image->h };
+	int r = SDL_BlitSurface(image, NULL, m->screen, &rcDest);
+
+	if (r) {
+		printf("Error blitting: %s\n", SDL_GetError());
+		exit(1);
+	}
+	SDL_FreeSurface(image);
+}
+
+static void cam_exposure_limits(struct sdl *m, struct v4l2_queryctrl *qctrl)
+{
+	qctrl->id = V4L2_CID_EXPOSURE_ABSOLUTE;
+	
+	if (v4l2_ioctl(m->fd, VIDIOC_QUERYCTRL, qctrl)) {
+		printf("Exposure absolute limits failed\n");
+		exit(1);
+	}
+
+	/* Minimum of 11300 gets approximately same range on ISO and
+	 * exposure axis. */
+	if (qctrl->minimum < 500)
+		qctrl->minimum = 500;
+}
+
+static void cam_set_exposure(struct sdl *m, double v)
+{
+	int cid = V4L2_CID_EXPOSURE_ABSOLUTE;
+	double res;
+	double range;
+	struct v4l2_queryctrl qctrl = { .id = cid };
+	struct v4l2_control ctrl = { .id = cid };
+
+	cam_exposure_limits(m, &qctrl);
+
+	if (v4l2_ioctl(m->fd, VIDIOC_G_CTRL, &ctrl)) {
+		printf("Can't get exposure parameters\n");
+		exit(1);
+	}
+
+	range = log2(qctrl.maximum) - log2(qctrl.minimum);
+	res = log2(qctrl.minimum) + v*range;
+	res = exp2(res);
+
+	v4l2_s_ctrl(m->fd, V4L2_CID_EXPOSURE_ABSOLUTE, res);
+}
+
+static double cam_convert_exposure(struct sdl *m, int v)
+{
+	int cid = V4L2_CID_EXPOSURE_ABSOLUTE;
+	double res;
+	struct v4l2_queryctrl qctrl = { .id = cid };
+
+	cam_exposure_limits(m, &qctrl);
+	res = (log2(v) - log2(qctrl.minimum)) / (log2(qctrl.maximum) - log2(qctrl.minimum));
+
+	return res;
+}
+
+static double cam_get_exposure(struct sdl *m)
+{
+	int cid = V4L2_CID_EXPOSURE_ABSOLUTE;
+	struct v4l2_control ctrl = { .id = cid };
+
+	if (v4l2_ioctl(m->fd, VIDIOC_G_CTRL, &ctrl))
+		return -1;
+
+	return cam_convert_exposure(m, ctrl.value);
+}
+
+static int cam_get_gain_iso(struct dev_info *dev)
+{
+	double x;
+
+	x = v4l2_g_ctrl(dev->fd, 0x00980913);
+	x = (x / 10); /* EV */
+	x = exp2(x);
+	x = 100*x;
+	return x;
+}
+
+static void cam_set_focus(struct sdl *m, double val)
+{
+	v4l2_s_ctrl(m->fd, V4L2_CID_FOCUS_ABSOLUTE, (val * m->focus_min) * (1023. / 20));
+}
+
+static double cam_convert_focus(struct sdl *m, double diopter)
+{
+	return diopter / m->focus_min;
+}
+
+static double cam_get_focus_diopter(struct sdl *m)
+{
+	return (v4l2_g_ctrl(m->fd, V4L2_CID_FOCUS_ABSOLUTE) * 20.) / 1023.;
+}
+
+static double cam_get_focus(struct sdl *m)
+{
+	return cam_convert_focus(m, cam_get_focus_diopter(m));
+}
+
+static void sdl_line_color(struct sdl *m, int x1, int y1, int x2, int y2, Uint32 color)
+{
+	SDL_Rect rcDest = { x1, y1, x2-x1+1, y2-y1+1};
+
+	SDL_FillRect(m->screen, &rcDest, color);
+}
+
+static void sdl_line(struct sdl *m, int x1, int y1, int x2, int y2)
+{
+	sdl_line_color(m, x1, y1, x2, y2, SDL_MapRGB( m->liveview->format, 255, 255, 255 ));
+}
+
+static void sdl_digit(struct sdl *m, int x, int y, int s, int i)
+{
+	unsigned char gr[] = { 0x5f, 0x0a, 0x76, 0x7a, 0x2b,
+			       0x79, 0x7d, 0x1a, 0x7f, 0x7b };
+	unsigned char g = gr[i];
+	/*
+              10
+	    01  02
+              20
+            04  08
+	      40
+	*/
+
+	if (g & 1) sdl_line(m, x, y, x, y+s);
+	if (g & 2) sdl_line(m, x+s, y, x+s, y+s);
+	if (g & 4) sdl_line(m, x, y+s, x, y+s+s);
+	if (g & 8) sdl_line(m, x+s, y+s, x+s, y+s+s);
+
+	if (g & 0x10) sdl_line(m, x, y, x+s, y);
+	if (g & 0x20) sdl_line(m, x, y+s, x+s, y+s);
+	if (g & 0x40) sdl_line(m, x, y+s+s, x+s, y+s+s);
+}
+
+static void sdl_number(struct sdl *m, int x, int y, int s, int digits, int i)
+{
+	int tot = s * 5;
+	x += tot * digits;
+	for (int j=0; j<digits; j++) {
+		sdl_digit(m, x+2, y+4, s*3, i%10);
+		i /= 10;
+		x -= tot;
+	}
+}
+
+static void sdl_icon_pos(struct sdl *m, int *x, int *y, double val)
+{
+	*x = m->wx - 10;
+	*y = val * m->wy;
+} 
+
+static void sdl_paint_ui_iso(struct sdl *m, double y_, int i)
+{
+	static char *iso_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"................",
+		"................",
+		"................",
+		".x..xx..x.......",
+		".x.x...x.x......",
+		".x..x..x.x......",
+		".x...x.x.x......",
+		".x.xx...x.......",
+		"................",
+		"................",
+		"................",
+		"................",
+	};
+
+	int x, y;
+
+	sdl_icon_pos(m, &x, &y, y_);
+	sdl_number(m, x-35, y-10, 1, 3, i);
+	sdl_paint_image(m, iso_xpm, x, y);
+}
+
+static void sdl_paint_ui_exposure(struct sdl *m, int t)
+{
+	static char *time_1_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"......x.........",
+		".....x..........",
+		"....x...........",
+		"...x............",
+		"................",
+		".xxx.xxxx.xxxx..",
+		"x....x....x.....",
+		".xx..xxx..x.....",
+		"...x.x....x.....",
+		"...x.x....x.....",
+		"xxx..xxxx.xxxx..",
+		"................",
+	};
+	int x, y;
+
+	sdl_icon_pos(m, &x, &y, cam_convert_exposure(m, 1000000/t));
+	sdl_number(m, x-35, y-10, 1, 3, t);
+	sdl_paint_image(m, time_1_xpm, x, y);
+}
+
+static void sdl_paint_boolean(struct sdl *m, char **image, int x, int y, int yes)
+{
+	static char *not_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"......xxxxx.....",
+		"....xx.....xx...",
+		"...x.........x..",
+		"..x........xx.x.",
+		"..x......xx...x.",
+		".x.....xx......x",
+		".x...xx........x",
+		"..xxx.........x.",
+		"..x...........x.",
+		"...x.........x..",
+		"....xx.....xx...",
+		"......xxxxx.....",
+	};
+
+	sdl_paint_image(m, image, x, y);
+	if (!yes)
+		sdl_paint_image(m, not_xpm,  16+x, y);      
+}
+
+static void sdl_paint_button(struct sdl *m, char **image, int x, int y, int yes)
+{
+	int bsx = m->wx/m->nx;
+	int bsy = m->wy/m->ny;
+	if (x < 0)
+		x += m->nx;
+	if (y < 0)
+		y += m->ny;
+	x = bsx/2 + x*bsx;
+	y = bsy/2 + y*bsy;
+	sdl_paint_boolean(m, image, x, y, yes);
+}
+
+static void sdl_paint_ui_focus(struct sdl *m, int f)
+{
+	static char *cm_xpm[] = {
+		"16 9 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"................",
+		"................",
+		"................",
+		"....###..#.#.##.",
+		"...#.....##.#..#",
+		"...#.....#..#..#",
+		"...#.....#..#..#",
+		"....###..#..#..#",
+		"................",
+	};
+	double dioptr = 1/(f/100.);
+	int x, y;
+
+	if (dioptr > m->focus_min)
+		return;
+
+	sdl_icon_pos(m, &x, &y, cam_convert_focus(m, dioptr));
+	sdl_paint_image(m, cm_xpm, x, y);
+	sdl_number(m, x-12, y-15, 1, 3, f);
+}
+
+static void sdl_paint_ui_bias(struct sdl *m, double v)
+{
+	static char *bias_xpm[] = {
+		"16 12 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"...#............",
+		"...#.......#....",
+		".#####....#.....",
+		"...#.....#......",
+		"...#....#.......",
+		".......#........",
+		"......#...#####.",
+		".....#..........",
+		"....#...........",
+		"...#............",
+		"................",
+		"................",
+	};
+	int x, y;
+
+	sdl_icon_pos(m, &x, &y, v);
+	sdl_paint_image(m, bias_xpm, x, y);
+	//sdl_number(m, x-12, y-15, 1, 3, f);
+}
+
+static void sdl_paint_slider(struct sdl *m)
+{
+	switch (m->slider_mode) {
+	case M_BIAS:
+		sdl_paint_ui_bias(m, 0.5);
+		return;
+	case M_EXPOSURE:
+		sdl_paint_ui_exposure(m, 10);
+		sdl_paint_ui_exposure(m, 100);
+		sdl_paint_ui_exposure(m, 999);
+#if 0
+		sdl_paint_ui_exposure(m, 10001);
+		sdl_paint_ui_exposure(m, 14002);
+#endif
+		return;
+	case M_GAIN:
+		sdl_paint_ui_iso(m, 0/4., 100);
+		sdl_paint_ui_iso(m, 1/4., 200);
+		sdl_paint_ui_iso(m, 2/4., 400);
+		sdl_paint_ui_iso(m, 3/4., 800);
+		return;
+	case M_FOCUS:
+		sdl_paint_ui_focus(m, 100);
+		sdl_paint_ui_focus(m, 40);
+		sdl_paint_ui_focus(m, 25);
+		sdl_paint_ui_focus(m, 16);	
+		sdl_paint_ui_focus(m, 10);
+		sdl_paint_ui_focus(m, 8);
+		sdl_paint_ui_focus(m, 6);
+		return;
+	}
+}
+
+static void sdl_paint_ui(struct sdl *m)
+{
+	static char *wait_xpm[] = {
+		"16 9 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"....########....",
+		".....#....#.....",
+		".....#....#.....",
+		"......#..#......",
+		".......##.......",
+		"......#..#......",
+		".....#....#.....",
+		".....#....#.....",
+		"....########....",
+	};
+
+	static char *ok_xpm[] = {
+		"16 9 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"...............#",
+		"............###.",
+		"..........##....",
+		"#.......##......",
+		".#.....#........",
+		"..#...#.........",
+		"..#..#..........",
+		"...##...........",
+		"...#............",
+	};
+
+	static char *exit_xpm[] = {
+		"16 9 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"....x......x....",
+		".....x....x.....",
+		"......x..x......",
+		".......xx.......",
+		".......xx.......",
+		"......x..x......",
+		".....x....x.....",
+		"....x......x....",
+		"................",
+	};
+
+	static char *af_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"................",
+		"................",
+		".....xxxxxxx....",
+		".....x..........",
+		".....x..........",
+		".x...xxxxx......",
+		"x.x..x..........",
+		"xxx..x..........",
+		"x.x..x..........",
+		"x.x..x..........",
+		"................",
+		"................",
+	};
+
+	static char *ae_xpm[] = {
+		"16 12 2 1",
+		"x c #ffffff",
+		". c #000000",
+		"................",
+		"................",
+		".....xxxxxxx....",
+		".....x..........",
+		".....x..........",
+		".x...xxxxx......",
+		"x.x..x..........",
+		"xxx..x..........",
+		"x.x..x..........",
+		"x.x..xxxxxxx....",
+		"................",
+		"................",
+	};
+    
+	static char *focus_xpm[] = {
+		"16 12 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"................",
+		"................",
+		"###..........###",
+		"#..............#",
+		"#.....####.....#",
+		".....#....#.....",
+		".....#....#.....",
+		"#.....####.....#",
+		"#..............#",
+		"###..........###",
+		"................",
+		"................",
+	};
+
+	static char *flash_xpm[] = {
+		"16 12 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"................",		
+		"..........#.....",
+		"........##......",
+		".......##.......",
+		"......##........",
+		".....########...",
+		"..........##....",
+		".......#.##.....",
+		".......###......",
+		".......####.....",
+		"................",
+		"................",
+	};
+
+	static char *wb_xpm[] = {
+		"16 12 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"................",
+		"................",
+		"................",
+		"#.....#..####...",
+		"#.....#..#...#..",
+		"#..#..#..####...",
+		"#..#..#..#...#..",
+		".##.##...####...",
+		"................",
+		"................",
+		"................",
+		"................",
+	};
+/* Template for more xpm's:
+	static char *empty_xpm[] = {
+		"16 12 2 1",
+		"# c #ffffff",
+		". c #000000",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+		"................",
+	};
+*/
+	SDL_FillRect(m->screen, NULL, SDL_MapRGB( m->liveview->format, 0, 0, 0 ));
+
+	{
+		/* Paint grid */
+		int x, y;
+		int nx = m->nx;
+		for (x=1; x<nx; x++) {
+			int x_ = (x*m->wx)/nx;
+			sdl_line_color(m, x_, 1, x_, m->wy-1, SDL_MapRGB( m->liveview->format, 40, 40, 40 ));
+		}
+
+		int ny = m->ny;
+		for (y=1; y<nx; y++) {
+			int y_ = (y*m->wy)/ny;
+			sdl_line_color(m, 1, y_, m->wx-1, y_, SDL_MapRGB( m->liveview->format, 40, 40, 40 ));
+		}
+				       
+	}
+
+	sdl_paint_image(m, wait_xpm,  m->wx/2,     m->wy/2);
+
+
+	sdl_paint_button(m, af_xpm, 0,  0, m->do_focus);
+	sdl_paint_button(m, ae_xpm, -1, 0, m->do_exposure);
+
+	sdl_paint_button(m, exit_xpm,   0, -1, 1);
+	sdl_paint_button(m, flash_xpm,  1, -1, m->do_flash);
+	sdl_paint_button(m, wb_xpm,     2, -1, m->do_white);
+	sdl_paint_button(m, focus_xpm, -1, -2, 1);
+	sdl_paint_button(m, ok_xpm,    -1, -1, 1);
+
+	sdl_paint_slider(m);
+	SDL_UpdateWindowSurface(m->window);
+}
+
+static double usec_to_time(double v)
+{
+	return 1/(v*.000001);
+}
+
+static void sdl_status_below(struct sdl *m, double avg)
+{
+	int ox = m->bx;
+	int oy = m->by+m->sy;
+	SDL_Rect rcDest = { ox, oy, m->sx, 25 /* m->by */ };
+
+	SDL_FillRect(m->screen, &rcDest, SDL_MapRGB( m->liveview->format, 30, 30, 30 ));
+
+	ox+=40;
+	sdl_number(m, ox, oy, 2, 3, avg*1000);
+
+	{
+		double focus, gain, exposure;
+
+		exposure = v4l2_g_ctrl(m->fd, V4L2_CID_EXPOSURE_ABSOLUTE);
+		gain = v4l2_g_ctrl(m->fd, 0x00980913);
+		focus = cam_get_focus_diopter(m);
+
+		ox+=40;
+		double x = usec_to_time(exposure);
+		if (x > 999) x = 999;
+		sdl_number(m, ox, oy, 2, 3, x);
+
+		ox+=40;
+		x = (gain / 10);
+		sdl_number(m, ox, oy, 2, 1, x);
+
+		ox+=20;
+		x = focus; /* diopters */
+		if (x == 0)
+			x = 999;
+		else
+			x = 100/x; /* centimeters */
+		sdl_number(m, ox, oy, 2, 3, x);
+	}
+
+	SDL_UpdateWindowSurfaceRects(m->window, &rcDest, 1);
+}
+
+static void sdl_status(struct sdl *m, double avg)
+{
+	int ox = 0;
+	int oy = m->wy/2;
+	int s = 3;
+	SDL_Rect rcDest = { ox, oy, s*25, s*40 };
+
+	SDL_FillRect(m->screen, &rcDest, SDL_MapRGB( m->liveview->format, 30, 30, 30 ));
+
+	sdl_number(m, ox, oy, s, 3, avg*1000);
+	oy += s*10;
+
+	{
+		double focus, gain, exposure;
+
+		exposure = v4l2_g_ctrl(m->fd, V4L2_CID_EXPOSURE_ABSOLUTE);
+		gain = cam_get_gain_iso(m->dev);
+		focus = cam_get_focus_diopter(m);
+
+		double x = usec_to_time(exposure);
+		if (x > 999) x = 999;
+		sdl_number(m, ox, oy, s, 3, x);
+
+		oy += s*10;
+		if (gain > 999)
+			gain = 999;
+		sdl_number(m, ox, oy, s, 3, gain);
+
+		oy += s*10;
+		x = focus; /* diopters */
+		if (x == 0)
+			x = 999;
+		else
+			x = 100/x; /* centimeters */
+		sdl_number(m, ox, oy, s, 3, x);
+	}
+
+	SDL_UpdateWindowSurfaceRects(m->window, &rcDest, 1);
+}
+static pixel buf_pixel(struct v4l2_format *fmt, unsigned char *buf, int x, int y)
+{
+	pixel p = { 0, 0, 0, 0 };
+	int pos = x + y*fmt->fmt.pix.width;
+
+	p.alpha = 128;
+
+	switch (fmt->fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGRBG10:
+#if 0
+		b = buf[pos*2];
+		b += buf[pos*2+1] << 8;
+		b /= 4;
+		if ((y % 2) == 0) {
+			switch (x % 2) {
+			case 0: p.g = b/2; break;
+			case 1: p.r = b; break;
+			}
+		} else {
+			switch (x % 2) {
+			case 0: p.b = b; break;
+			case 1: p.g = b/2; break;
+			}
+		}
+#else
+		{
+			short *b2 = (void *)buf;
+			x &= ~1;
+			y &= ~1;
+			p.g = b2[x + y*fmt->fmt.pix.width] /4;
+			p.r = b2[x + y*fmt->fmt.pix.width+1] /4;
+			p.b = b2[x + (y+1)*fmt->fmt.pix.width] /4;
+		}
+#endif
+		break;
+
+	case V4L2_PIX_FMT_RGB24:
+		pos *= 3;
+		p.r = buf[pos];
+		p.g = buf[pos+1];
+		p.b = buf[pos+2];
+		break;
+
+	default:
+		printf("Wrong pixel format!\n");
+		fmt_print(fmt);
+		exit(1);
+	}
+
+	return p;
+}
+
+static char *fmt_name(struct v4l2_format *fmt)
+{
+	switch (fmt->fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGRBG10:
+		return "GRBG10";
+	case V4L2_PIX_FMT_RGB24:
+		return "RGB24";
+	default:
+		return "unknown";
+	}
+}
+
+static void sdl_handle_focus(struct sdl *m, float how)
+{
+	v4l2_set_control(m->fd, V4L2_CID_FOCUS_ABSOLUTE, 65535. * how);
+}
+
+static void sdl_key(struct sdl *m, int c)
+{
+	switch (c) {
+	case 27: exit(1); break;
+	case 'q': sdl_handle_focus(m, 0.); break;
+	case 'w': sdl_handle_focus(m, 1/6.); break;
+	case 'e': sdl_handle_focus(m, 1/3.); break;
+	case 'r': sdl_handle_focus(m, 1/2.); break;
+	case 't': sdl_handle_focus(m, 1/1); break;
+	case 'y': sdl_handle_focus(m, 1/.8); break;
+	case 'u': sdl_handle_focus(m, 1/.5); break;
+	case 'i': sdl_handle_focus(m, 1/.2); break;
+	case 'o': sdl_handle_focus(m, 1/.1); break;
+	case 'p': sdl_handle_focus(m, 1/.05); break;
+	case SDLK_SPACE: /* save_image(); */ printf("Should save jpeg.\n"); break;
+	default: printf("Unknown key %d / %c", c, c);
+	}
+}
+
+static int sdl_render_statistics(struct sdl *m)
+{
+	pixel white;
+	double focus, gain, exposure;
+
+	white.r = (Uint8)0xff;
+	white.g = (Uint8)0xff;
+	white.b = (Uint8)0xff;
+	white.alpha = (Uint8)128;
+
+	exposure = cam_get_exposure(m);
+	gain = v4l2_get_control(m->fd, 0x00980913) / 65535.;
+	focus = cam_get_focus(m);
+
+	for (int x=0; x<m->sx && x<m->sx*focus; x++)
+		sfc_put_pixel(m->liveview, x, 0, &white);
+
+	for (int y=0; y<m->sy && y<m->sy*gain; y++)
+		sfc_put_pixel(m->liveview, 0, y, &white);
+
+	for (int y=0; y<m->sy && y<m->sy*exposure; y++)
+		sfc_put_pixel(m->liveview, m->sx-1, y, &white);
+
+	for (int x=0; x<m->sx; x++)
+		sfc_put_pixel(m->liveview, x, m->sy-1, &white);
+
+	return 0;
+}
+
+static void sdl_render(struct sdl *m, unsigned char *buf, struct v4l2_format *fmt)
+{
+	float zoom = m->zoom;
+	if (!m->window) 
+		return;
+
+	sdl_begin_paint(m);
+	int x0 = (fmt->fmt.pix.width - m->sx*m->factor/zoom)/2;
+	int y0 = (fmt->fmt.pix.height - m->sy*m->factor/zoom)/2;
+
+	for (int y = 0; y < m->sy; y++)
+		for (int x = 0; x < m->sx; x++) {
+			int x1 = x0+x*m->factor/zoom;
+			int y1 = y0+y*m->factor/zoom;
+			pixel p = buf_pixel(fmt, buf, x1, y1);
+			p.alpha = 128;
+			sfc_put_pixel(m->liveview, x, y, &p);
+		}
+
+	sdl_render_statistics(m);
+	sdl_finish_paint(m);
+}
+
+static void sdl_sync_settings(struct sdl *m)
+{
+	printf("Autofocus: "); v4l2_s_ctrl(m->fd, V4L2_CID_FOCUS_AUTO, m->do_focus);
+	printf("Autogain: " ); v4l2_s_ctrl(m->fd, V4L2_CID_AUTOGAIN, m->do_exposure);
+	printf("Autowhite: "); v4l2_s_ctrl(m->fd, V4L2_CID_AUTO_WHITE_BALANCE, m->do_white);
+	v4l2_s_ctrl(m->fd, 0x009c0901, m->do_flash ? 2 : 0);
+}
+
+static void sdl_init_window(struct sdl *m)
+{
+	if (m->do_full) {
+		m->wx = 800;
+		m->wy = 480;
+	} else {
+		m->wx = 800;
+		m->wy = 429;
+	}
+
+	SDL_SetWindowFullscreen(m->window, m->do_full*SDL_WINDOW_FULLSCREEN_DESKTOP);
+
+	m->screen = SDL_GetWindowSurface(m->window);
+	if (!m->screen) {
+		printf("Couldn't create screen\n");
+		exit(1);
+	}
+}
+
+static void sdl_init(struct sdl *m, struct dev_info *dev)
+{
+	m->fd = dev->fd;
+	m->dev = dev;
+
+	if (SDL_Init(SDL_INIT_VIDEO) < 0) {
+		printf("Could not init SDL\n");
+		exit(1);
+	}
+
+	atexit(SDL_Quit);
+
+	m->nx = 6;
+	m->ny = 4;
+
+	m->do_flash = 1;
+	m->do_focus = 0;
+	m->do_exposure = 1;
+	m->focus_min = 5;
+	m->do_white = 0;
+	m->do_big = 0;
+	m->do_full = 0;
+	m->zoom = 1;
+
+	m->window = SDL_CreateWindow("Camera", SDL_WINDOWPOS_UNDEFINED,
+				     SDL_WINDOWPOS_UNDEFINED, 800, 429,
+				     SDL_WINDOW_SHOWN | 
+				     m->do_full * SDL_WINDOW_FULLSCREEN_DESKTOP);
+	if (m->window == NULL) {
+		printf("Window could not be created! SDL_Error: %s\n", SDL_GetError());
+		exit(1);
+	}
+
+	sdl_init_window(m);
+}
+
+static void sdl_set_size(struct sdl *m, int _sx)
+{
+	m->sx = _sx;
+	m->factor = (float) m->dev->fmt.fmt.pix.width / m->sx;
+	m->sy = m->dev->fmt.fmt.pix.height / m->factor;
+
+	m->bx = (m->wx-m->sx)/2;
+	m->by = (m->wy-m->sy)/2;
+
+	m->liveview = SDL_CreateRGBSurface(0,m->sx,m->sy,32,0,0,0,0);
+	if (!m->liveview) {
+		printf("Couldn't create liveview\n");
+		exit(1);
+	}
+
+	sdl_paint_ui(m);
+	sdl_sync_settings(m);
+}
+
+static struct sdl sdl;
+
+static void cam_pgm_write(struct dev_info *dev, struct v4l2_format *fmt, unsigned char *img, char *out_name)
+{
+	char buf[1024];
+	double focus, gain, exposure;
+
+	exposure = v4l2_get_control(dev->fd, V4L2_CID_EXPOSURE_ABSOLUTE) / 65536.;
+	gain = v4l2_get_control(dev->fd, 0x00980913) / 65536.;
+	focus = v4l2_get_control(dev->fd, V4L2_CID_FOCUS_ABSOLUTE) / 65536.;
+
+	sprintf(buf, "# SDLcam raw image\n# Exposure %f, gain %f, focus %f\n", exposure, gain, focus);
+
+	pgm_write(fmt, img, out_name, buf);
+}
+
+#ifdef COOKED
+static void ppm_write(struct v4l2_format *fmt, unsigned char *img, char *out_name)
+{
+	FILE *fout;
+	fout = fopen(out_name, "w");
+	if (!fout) {
+		perror("Cannot open image");
+		exit(EXIT_FAILURE);
+	}
+	switch (fmt->fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_RGB24:
+		printf("ok\n");
+		break;
+	default:
+		printf("Bad pixel format\n");
+		exit(1);
+	}
+
+	fprintf(fout, "P6\n%d %d 255\n",
+		fmt->fmt.pix.width, fmt->fmt.pix.height);
+	fwrite(img, fmt->fmt.pix.width, 3*fmt->fmt.pix.height, fout);
+	fclose(fout);
+}
+
+/**
+   Write image to jpeg file.
+   \param img image to write
+*/
+static void jpeg_write(struct v4l2_format *fmt, unsigned char *img, char *jpegFilename)
+{
+	struct jpeg_compress_struct cinfo;
+	struct jpeg_error_mgr jerr;
+
+	JSAMPROW row_pointer[1];
+	FILE *outfile = fopen(jpegFilename, "wb");
+	if (!outfile) {
+		printf("Can't open jpeg for writing.\n");
+		exit(2);
+	}
+
+	/* create jpeg data */
+	cinfo.err = jpeg_std_error(&jerr);
+	jpeg_create_compress(&cinfo);
+	jpeg_stdio_dest(&cinfo, outfile);
+
+	/* set image parameters */
+	cinfo.image_width = fmt->fmt.pix.width;
+	cinfo.image_height = fmt->fmt.pix.height;
+	cinfo.input_components = 3;
+	switch (fmt->fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGRBG10:
+	case V4L2_PIX_FMT_RGB24:
+		cinfo.in_color_space = JCS_RGB;
+		break;
+	default:
+		printf("Need to specify colorspace!\n");
+		exit(1);
+	}
+
+	/* set jpeg compression parameters to default */
+	jpeg_set_defaults(&cinfo);
+	jpeg_set_quality(&cinfo, 90, TRUE);
+
+	jpeg_start_compress(&cinfo, TRUE);
+
+	/* feed data */
+	while (cinfo.next_scanline < cinfo.image_height) {
+		row_pointer[0] = &img[cinfo.next_scanline * cinfo.image_width *  cinfo.input_components];
+		jpeg_write_scanlines(&cinfo, row_pointer, 1);
+	}
+
+	jpeg_finish_compress(&cinfo);
+	jpeg_destroy_compress(&cinfo);
+	fclose(outfile);
+}
+
+static void convert_rgb(struct dev_info *dev, struct v4l2_format sfmt, void *buf, struct v4l2_format dfmt, void *buf2, int wb)
+{
+	struct v4lconvert_data *data = v4lconvert_create(dev->fd);
+	int res;
+
+	printf("Converting first.");
+	if (wb) {
+		struct v4l2_control ctrl;
+		ctrl.id = V4L2_CID_AUTO_WHITE_BALANCE;
+		ctrl.value = 1;
+		v4lconvert_vidioc_s_ctrl(data, &ctrl);
+	}
+	res = v4lconvert_convert(data, &sfmt, &dfmt, buf, SIZE, buf2, SIZE);
+	printf("Converting: %d\n", res);
+	v4lconvert_destroy(data);
+}
+#endif
+
+static void any_write(struct dev_info *dev)
+{
+	char name[1024];
+	unsigned char *buf;
+	time_t t = time(NULL);
+
+	buf = dev->buf;
+
+	if (1) {
+		sprintf(name, "/data/tmp/delme_%d.%s", (int) t, "pgm");
+
+		if (dev->fmt.fmt.pix.pixelformat != V4L2_PIX_FMT_SGRBG10)
+			printf("Not in bayer10, can't write raw.\n");
+		else
+			cam_pgm_write(dev, &dev->fmt, buf, name);
+	}
+
+#ifdef COOKED
+	int ppm = 0;
+	/* FIXME: full resolution picture is too big to be put on stack */
+	static unsigned char buf2[SIZE];
+
+	sprintf(name, "/data/tmp/delme_%d.%s", (int) t, ppm ? "ppm" : "jpg");
+	if (dev->fmt.fmt.pix.pixelformat != V4L2_PIX_FMT_RGB24) {
+		struct v4l2_format dest_fmt;
+
+		dest_fmt = dev->fmt;
+		dest_fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;
+		dest_fmt.fmt.pix.bytesperline = 3 * dest_fmt.fmt.pix.width;
+		dest_fmt.fmt.pix.sizeimage = 3 * dest_fmt.fmt.pix.width * dest_fmt.fmt.pix.height;
+
+		convert_rgb(dev, dev->fmt, buf, dest_fmt, buf2, 0);
+		buf = buf2;
+		//convert_rgb(dev, dest_fmt, buf2, dest_fmt, buf, 0);
+	}
+	if (ppm)
+		ppm_write(&dev->fmt, buf, name);
+	else
+		jpeg_write(&dev->fmt, buf, name);
+#endif
+}
+
+static void sdl_mouse(struct sdl *m, SDL_Event event)
+{
+	int ax = 0, ay = 0;
+	int nx = event.button.x / (m->wx/m->nx), ny = event.button.y / (m->wy/m->ny);
+	if (nx >= m->nx/2)
+		nx -= m->nx;
+	if (ny >= m->ny/2)
+		ny -= m->ny;
+
+	printf("Button %d %d\n", nx, ny);
+
+	/* Virtual slider */
+	if (nx == -2) {
+		double value = (double) event.button.y / m->wy;
+		switch (m->slider_mode) {
+		case M_BIAS: {
+			double ev = value - .5; /* -.5 .. +.5 */
+			ev *= 3000;
+			printf("Exposure bias: %f mEV %d\n", ev, (int) ev);
+			if (v4l2_s_ctrl(m->fd, V4L2_CID_AUTO_EXPOSURE_BIAS, ev) < 0) {
+				printf("Could not set exposure bias\n");
+			}
+		}
+			return;
+		case M_EXPOSURE:
+			m->do_exposure = 0;
+			cam_set_exposure(m, value);
+			sdl_sync_settings(m);
+			return;
+		case M_GAIN:
+			m->do_exposure = 0;
+			v4l2_set_control(m->fd, 0x00980913, value * 65535);
+			sdl_sync_settings(m);
+			return;
+		case M_FOCUS:
+			cam_set_focus(m, value);
+			return;
+		}
+	}
+
+	switch (ny) {
+	case 0:
+		switch (nx) {
+		case 0:
+			m->do_focus ^= 1;
+			sdl_paint_ui(m);
+			sdl_sync_settings(m);
+			return;
+		case -1:
+			m->do_exposure ^= 1;
+			sdl_paint_ui(m);
+			sdl_sync_settings(m);
+			return;
+		}
+		break;
+	case 1:
+		switch (nx) {
+		case -1:
+			m->slider_mode = (m->slider_mode + 1) % M_NUM;
+			sdl_paint_ui(m);
+		}
+		break;
+	case -2:
+		switch (nx) {
+#if 0
+		case -2:
+			m->do_full ^= 1;
+			sdl_init_window(m);
+			sdl_paint_ui(m);
+			return;
+		case -1:
+			if (m->zoom == 1) {
+				m->zoom = 4;
+				return;
+			}
+			m->zoom = 1;
+			return;
+#endif
+		case -1:
+			v4l2_s_ctrl(m->fd, V4L2_CID_AUTO_FOCUS_STATUS, 1);
+			return;
+		break;
+		}
+	case -1:
+		switch (nx) {
+		case 0:
+			exit(0);
+		case 1:
+			m->do_flash ^= 1;
+			sdl_paint_ui(m);
+			sdl_sync_settings(m);
+			return;
+		case 2:
+			m->do_white ^= 1;
+			sdl_paint_ui(m);
+			sdl_sync_settings(m);
+			return;
+		case -3:
+			m->do_big ^= 1;
+			if (m->do_big)
+				sdl_set_size(m, m->do_full ? 630:512);
+			else
+				sdl_set_size(m, 256);
+			return;
+		case -1:
+			sdl_paint_ui(m);
+			any_write(m->dev);
+			return;
+		}
+		break;
+	}
+			
+	if (event.button.x > m->wx-m->bx)
+		ax = 1;
+	if (event.button.x < m->bx)
+		ax = -1;
+
+	if (event.button.y > m->wy-m->by)
+		ay = 1;
+	if (event.button.y < m->by)
+		ay = -1;
+	    
+	printf("mouse button at...%d, %d area %d, %d\n", event.button.x, event.button.y,
+	       ax, ay);
+}
+
+static void sdl_iteration(struct sdl *m)
+{
+	SDL_Event event;
+
+	while(SDL_PollEvent(&event)) {
+		switch(event.type) {
+		case SDL_QUIT:
+			exit(1);
+			break;
+		case SDL_KEYDOWN:
+			printf("key pressed... %c\n", event.key.keysym.sym);
+			/* SDLK_A, SDLK_LEFT, SDLK_RETURN, SDLK_BACKSPACE, SDLK_SPACE */
+			switch (event.key.keysym.sym) {
+			default: sdl_key(m, event.key.keysym.sym);
+			}
+			break;
+		case SDL_WINDOWEVENT:
+			if (event.window.event == SDL_WINDOWEVENT_EXPOSED)
+				sdl_paint_ui(m);
+			break;
+		case SDL_MOUSEBUTTONDOWN:
+			sdl_mouse(m, event);
+			break;
+		}
+	}
+}
+
+static void cam_open(struct dev_info *dev)
+{
+	struct v4l2_format *fmt = &dev->fmt;
+
+	dev->fd = v4l2_open("/dev/video_ccdc", O_RDWR);
+
+	fmt->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	fmt->fmt.pix.pixelformat = V4L2_PIX_FMT_SGRBG10;
+//	fmt->fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;
+	fmt->fmt.pix.field = V4L2_FIELD_NONE;
+	fmt->fmt.pix.width = SX;
+	fmt->fmt.pix.height = SY;
+
+	v4l2_s_ctrl(dev->fd, V4L2_CID_AUTO_FOCUS_STATUS, 0);
+	v4l2_set_focus(dev->fd, 50);
+
+	printf("ioctl = %d\n", v4l2_ioctl(dev->fd, VIDIOC_S_FMT, fmt));
+
+	printf("capture is %lx %s %d x %d\n", (unsigned long) fmt->fmt.pix.pixelformat, fmt_name(fmt), fmt->fmt.pix.width, fmt->fmt.pix.height);
+}
+
+/* ------------------------------------------------------------------ */
+
+
+static struct dev_info dev;
+
+int main(void)
+{
+	int i;
+	struct v4l2_format *fmt = &dev.fmt;
+
+	dtime();
+	cam_open(&dev);
+
+	/* factor == 3 still fits window, but very slow over ssh. (Fast enough on localhost) */
+	/* factor == 5 nice over ssh */
+	/* == 1.7, full-screen video for 800x600 */
+	/* == 2.5, full-screen video for 1200x, 516 */
+	sdl_init(&sdl, &dev);
+	sdl_set_size(&sdl, 256);
+  
+	/* In 800x600 "raw" mode, this should take cca 17.8 seconds (without
+	   sdl output. CPU usage should be cca 5% without conversion). That's 28 fps.
+	   (benchmark with i<500)
+
+	   switched to separate application -- not in library:
+	   1296x986, i<20, with RGB24 conversion: 32 sec
+	   1296x986, i<20, raw _SGRBG10: 6.3 sec
+
+	   i<500, 2m59, 86%, RGB24
+	   i<500, 1m43, 36%, b10
+	*/
+	double loop = dtime(), max = 0, avg = .200;
+	if (dev.debug & D_TIMING)
+		printf("startup took %f\n", loop);
+	
+	for (i=0; i<500000; i++) {
+		int num = v4l2_read(dev.fd, dev.buf, SIZE);
+		if (num < 0)
+			return 1;
+		/* Over USB connection, rendering every single frame slows
+		   execution down from 23 seconds to 36 seconds. */
+#if 1
+		{
+			/* Render takes 80msec over ssh, 47msec on localhost */
+			double d = dtime();
+			sdl_render(&sdl, dev.buf, fmt);
+			if (dev.debug & D_TIMING)
+				printf("Render took %f\n", dtime() - d);
+		}
+		{
+			/* Takes cca 10msec over ssh */
+			double d = dtime();
+			for (int i = 0; i<1; i++)
+				sdl_status(&sdl, avg);
+			if (dev.debug & D_TIMING)
+				printf("Status took %f\n", dtime() - d);
+		}
+#endif
+		sdl_iteration(&sdl);
+		double now = dtime();
+		if (now - loop > max)
+			max = now - loop;
+		double c = 0.03;
+		avg = (now - loop) * c + avg * (1-c);
+		if (dev.debug & D_TIMING)
+			printf("Iteration %f, maximum %f, average %f\n", now-loop, max, avg);
+		loop = now;
+	}
+	return 0;
+}
diff --git a/contrib/test/unused-v4l2sdl.c b/contrib/test/unused-v4l2sdl.c
new file mode 100644
index 0000000..fe79b9e
--- /dev/null
+++ b/contrib/test/unused-v4l2sdl.c
@@ -0,0 +1,124 @@
+/*
+
+gcc sdlcam.c -I. -I../../include -I../../lib/include -I../../lib/libv4l2 -I../../lib/libv4lconvert/processing -I../../lib/libv4lconvert -std=c99 -lSDL2 -lSDL2_image -ljpeg -lefence ../../lib/libv4l2/.libs/libv4l2.a  ../../lib/libv4lconvert/.libs/libv4lconvert.a && time ./a.out
+
+  libv4l is problematic:
+  1) It converts image to RGB24, but we'd prefer to stay in GRBG10
+  2) It only uses 8-bits per color internally. Cameras such as Nikon D500 
+     store 14-bits per channel. Even N900 stores 10.
+  3) We'd really like to know units for exposure/gain/focus.
+  4) It does not work with subdevices -- at all.
+  5) It steps up time before stepping up gain -- unsuitable for camera.
+  6) Too much resolution in time at the high end, and not enough at the low end, thus oscillations
+
+*/
+
+void imageStatistics(FCam::Image img)
+{
+	int sx, sy;
+
+	sx = img.size().width;                                                          
+	sy = img.size().height;                                                         
+	printf("Image is %d x %d, ", sx, sy);                                           
+
+	printf("(%d) ", img.brightness(sx/2, sy/2));
+
+	int dark = 0;                                                                   
+	int bright = 0;                                                                 
+	int total = 0;                                                                  
+#define RATIO 10
+	for (int y = sy/(2*RATIO); y < sy; y += sy/RATIO)                               
+		for (int x = sx/(2*RATIO); x < sx; x += sx/RATIO) {                    
+			int br = img.brightness(x, y);                               
+
+			if (!d_raw) {
+				/* It seems real range is 60 to 218 */
+				if (br > 200)
+					bright++;                                               
+				if (br < 80)
+					dark++;
+			} else {
+				/* there's a lot of noise, it seems black is commonly 65..71,
+				   bright is cca 1023 */
+				if (br > 1000)
+					bright++;
+				if (br < 75)
+					dark++;
+			}
+			total++;                                                      
+		}
+
+	printf("%d dark %d bri,", dark, bright);                     
+
+	long sharp = 0;
+	for (int y = sy/3; y < 2*(sy/3); y+=sy/12) {
+		int b = -1;
+		for (int x = sx/3; x < 2*(sx/3); x++) {
+			int b2;                                                                
+			b2 = img.brightness(x, y/2);                                          
+			if (b != -1)
+				sharp += (b-b2) * (b-b2);                                              
+			b = b2;                                                                
+		}
+	}
+	printf("sh %d\n", sharp);
+}
+
+static void v4l2_statistics(int index, struct v4l2_buffer *buf)
+{
+	unsigned char *b;
+	struct v4l2_format *fmt;
+
+	fmt = &devices[index].src_fmt;
+	b = devices[index].frame_pointers[buf->index];
+
+	if (!(devices[index].frame%3))
+		v4l2_auto_exposure(index, buf);
+	
+	int sh = v4l2_sharpness(b, fmt);
+	v4l2_auto_focus_single(&devices[index], sh);
+	
+	devices[index].frame++;
+	if (!(devices[index].frame%4))
+		sdl_render(&sdl, b, fmt);
+}
+
+static int v4l2_set_autogain(int fd)
+{
+	if (v4l2_s_ctrl(fd, V4L2_CID_AUTOGAIN, 1) < 0) {
+		printf("Could not set autogain\n");
+	}
+	return 0;
+}
+
+static int v4l2_set_exposure(int fd, int exposure)
+{
+	if (v4l2_s_ctrl(fd, V4L2_CID_EXPOSURE_ABSOLUTE, exposure) < 0) {
+		printf("Could not set exposure\n");
+	}
+	return 0;
+}
+
+static int v4l2_set_gain(int fd, int gain)
+{
+	if (v4l2_s_ctrl(fd, 0x00980913, gain) < 0) {
+		printf("Could not set gain\n");
+	}
+	return 0;
+}
+
+static double gain_to_EV(double v)
+{
+	return -(log(v)/log(2));
+}
+
+static double EV_to_lux(double v)
+{
+	return 2.5 * pow(2, v);
+}
+
+/* Takes inverse 1/time! */
+static double time_to_EV(double v) {
+	return 5+log(v)/log(2);
+}
+
diff --git a/contrib/test/v4l2grab.c b/contrib/test/v4l2grab.c
index 778c51c..8b25b45 100644
--- a/contrib/test/v4l2grab.c
+++ b/contrib/test/v4l2grab.c
@@ -326,7 +326,7 @@ static int capture(char *dev_name, int x_res, int y_res, int n_frames,
  * capture routine
  */
 
-const char *argp_program_version = "V4L2 grabber version " V4L_UTILS_VERSION;
+const char *argp_program_version = "V4L2 grabber version <local>";
 const char *argp_program_bug_address = "Mauro Carvalho Chehab <m.chehab@samsung.com>";
 
 static const char doc[] = "\nCapture images using libv4l, storing them as ppm files\n";
diff --git a/lib/libv4l2/libv4l2-priv.h b/lib/libv4l2/libv4l2-priv.h
index 343db5e..a6bc48e 100644
--- a/lib/libv4l2/libv4l2-priv.h
+++ b/lib/libv4l2/libv4l2-priv.h
@@ -26,6 +26,7 @@
 #include "../libv4lconvert/libv4lsyscall-priv.h"
 
 #define V4L2_MAX_DEVICES 16
+#define V4L2_MAX_SUBDEVS 8
 /* Warning when making this larger the frame_queued and frame_mapped members of
    the v4l2_dev_info struct can no longer be a bitfield, so the code needs to
    be adjusted! */
@@ -104,6 +105,7 @@ struct v4l2_dev_info {
 	void *plugin_library;
 	void *dev_ops_priv;
 	const struct libv4l_dev_ops *dev_ops;
+        int subdev_fds[V4L2_MAX_SUBDEVS];
 };
 
 /* From v4l2-plugin.c */
diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
index 2db25d1..f9e2711 100644
--- a/lib/libv4l2/libv4l2.c
+++ b/lib/libv4l2/libv4l2.c
@@ -1,3 +1,4 @@
+/* -*- c-file-style: "linux" -*- */
 /*
 #             (C) 2008 Hans de Goede <hdegoede@redhat.com>
 
@@ -794,13 +795,21 @@ no_capture:
 		v4lconvert_set_fps(devices[index].convert, V4L2_DEFAULT_FPS);
 	v4l2_update_fps(index, &parm);
 
+	devices[index].subdev_fds[0] = SYS_OPEN("/dev/video_sensor", O_RDWR, 0);
+	devices[index].subdev_fds[1] = SYS_OPEN("/dev/video_focus", O_RDWR, 0);
+	devices[index].subdev_fds[2] = SYS_OPEN("/dev/video_flash", O_RDWR, 0);
+	devices[index].subdev_fds[3] = -1;
+
+	printf("Sensor: %d, focus: %d\n", devices[index].subdev_fds[0], 
+	       devices[index].subdev_fds[1]);
+
 	V4L2_LOG("open: %d\n", fd);
 
 	return fd;
 }
 
 /* Is this an fd for which we are emulating v4l1 ? */
-static int v4l2_get_index(int fd)
+int v4l2_get_index(int fd)
 {
 	int index;
 
@@ -1056,6 +1065,21 @@ static int v4l2_s_fmt(int index, struct v4l2_format *dest_fmt)
 	return 0;
 }
 
+static int v4l2_propagate_ioctl(int index, unsigned long request, void *arg)
+{
+	int i = 0;
+	int result;
+	while (1) {
+		if (devices[index].subdev_fds[i] == -1)
+			return -1;
+		result = SYS_IOCTL(devices[index].subdev_fds[i], request, arg);
+		if (result == 0)
+			return 0;
+		i++;
+	}
+	return -1;
+}
+
 int v4l2_ioctl(int fd, unsigned long int request, ...)
 {
 	void *arg;
@@ -1185,14 +1209,20 @@ no_capture_request:
 	switch (request) {
 	case VIDIOC_QUERYCTRL:
 		result = v4lconvert_vidioc_queryctrl(devices[index].convert, arg);
+		if (result == -1)
+			result = v4l2_propagate_ioctl(index, request, arg);
 		break;
 
 	case VIDIOC_G_CTRL:
 		result = v4lconvert_vidioc_g_ctrl(devices[index].convert, arg);
+		if (result == -1)
+			result = v4l2_propagate_ioctl(index, request, arg);
 		break;
 
 	case VIDIOC_S_CTRL:
 		result = v4lconvert_vidioc_s_ctrl(devices[index].convert, arg);
+		if (result == -1)
+			result = v4l2_propagate_ioctl(index, request, arg);
 		break;
 
 	case VIDIOC_G_EXT_CTRLS:
@@ -1739,7 +1769,8 @@ int v4l2_set_control(int fd, int cid, int value)
 
 	result = v4lconvert_vidioc_queryctrl(devices[index].convert, &qctrl);
 	if (result)
-		return result;
+		if (v4l2_propagate_ioctl(index, VIDIOC_QUERYCTRL, &qctrl))
+			return -1;
 
 	if (!(qctrl.flags & V4L2_CTRL_FLAG_DISABLED) &&
 			!(qctrl.flags & V4L2_CTRL_FLAG_GRABBED)) {
@@ -1750,6 +1781,8 @@ int v4l2_set_control(int fd, int cid, int value)
 				qctrl.minimum;
 
 		result = v4lconvert_vidioc_s_ctrl(devices[index].convert, &ctrl);
+		if (result == -1)
+			result = v4l2_propagate_ioctl(index, VIDIOC_S_CTRL, &ctrl);
 	}
 
 	return result;
@@ -1768,7 +1801,8 @@ int v4l2_get_control(int fd, int cid)
 	}
 
 	if (v4lconvert_vidioc_queryctrl(devices[index].convert, &qctrl))
-		return -1;
+		if (v4l2_propagate_ioctl(index, VIDIOC_QUERYCTRL, &qctrl))
+			return -1;
 
 	if (qctrl.flags & V4L2_CTRL_FLAG_DISABLED) {
 		errno = EINVAL;
diff --git a/lib/libv4lconvert/Makefile.am b/lib/libv4lconvert/Makefile.am
index f266f3e..9557a9c 100644
--- a/lib/libv4lconvert/Makefile.am
+++ b/lib/libv4lconvert/Makefile.am
@@ -17,6 +17,7 @@ libv4lconvert_la_SOURCES = \
   stv0680.c cpia1.c se401.c jpgl.c jpeg.c jl2005bcd.c \
   control/libv4lcontrol.c control/libv4lcontrol.h control/libv4lcontrol-priv.h \
   processing/libv4lprocessing.c processing/whitebalance.c processing/autogain.c \
+  processing/focus.c \
   processing/gamma.c processing/libv4lprocessing.h processing/libv4lprocessing-priv.h \
   helper-funcs.h libv4lconvert-priv.h libv4lsyscall-priv.h \
   tinyjpeg.h tinyjpeg-internal.h
diff --git a/lib/libv4lconvert/control/libv4lcontrol.c b/lib/libv4lconvert/control/libv4lcontrol.c
index 1e784ed..e8c67e2 100644
--- a/lib/libv4lconvert/control/libv4lcontrol.c
+++ b/lib/libv4lconvert/control/libv4lcontrol.c
@@ -638,7 +638,7 @@ struct v4lcontrol_data *v4lcontrol_create(int fd, void *dev_ops_priv,
 
 	/* If the device always needs conversion, we can add fake controls at no cost
 	   (no cost when not activated by the user that is) */
-	if (always_needs_conversion || v4lcontrol_needs_conversion(data)) {
+	if (1 || always_needs_conversion || v4lcontrol_needs_conversion(data)) {
 		for (i = 0; i < V4LCONTROL_AUTO_ENABLE_COUNT; i++) {
 			ctrl.id = fake_controls[i].id;
 			rc = data->dev_ops->ioctl(data->dev_ops_priv, data->fd,
@@ -678,6 +678,16 @@ struct v4lcontrol_data *v4lcontrol_create(int fd, void *dev_ops_priv,
 		break;
 	}
 
+       data->controls |= 1 << V4LCONTROL_AUTOGAIN |
+	 	         1 << V4LCONTROL_AUTOGAIN_TARGET |
+	                 1 << V4LCONTROL_EXPOSURE_BIAS |
+	 	         1 << V4LCONTROL_AUTO_FOCUS |
+	 	         1 << V4LCONTROL_FOCUS_START |
+	 		 1 << V4LCONTROL_FOCUS_STOP |
+	 		 1 << V4LCONTROL_FOCUS_STATUS |
+	 		 1 << V4LCONTROL_FOCUS_RANGE;
+
+
 	/* Allow overriding through environment */
 	s = getenv("LIBV4LCONTROL_CONTROLS");
 	if (s)
@@ -841,6 +851,60 @@ static const struct v4l2_queryctrl fake_controls[V4LCONTROL_COUNT] = {
 		.step = 1,
 		.default_value = 100,
 		.flags = V4L2_CTRL_FLAG_SLIDER
+	},  {
+	        .id = V4L2_CID_FOCUS_AUTO,
+		.type = V4L2_CTRL_TYPE_INTEGER,
+		.name =  "Auto Focus enabled",
+		.minimum = 0,
+		.maximum = 1,
+		.step = 1,
+		.default_value = 0,
+		.flags = 0
+	},  {
+	        .id = V4L2_CID_AUTO_FOCUS_START,
+		.type = V4L2_CTRL_TYPE_INTEGER,
+		.name =  "Focus start",
+		.minimum = 0,
+		.maximum = 1,
+		.step = 1,
+		.default_value = 0,
+		.flags = 0
+	},  {
+	        .id = V4L2_CID_AUTO_FOCUS_STOP,
+		.type = V4L2_CTRL_TYPE_INTEGER,
+		.name =  "",
+		.minimum = 0,
+		.maximum = 1,
+		.step = 1,
+		.default_value = 0,
+		.flags = 0
+	},  {
+	        .id = V4L2_CID_AUTO_FOCUS_STATUS,
+		.type = V4L2_CTRL_TYPE_INTEGER,
+		.name =  "",
+		.minimum = 0,
+		.maximum = 1,
+		.step = 1,
+		.default_value = 0,
+		.flags = 0
+	}, {
+	        .id = V4L2_CID_AUTO_FOCUS_RANGE,
+		.type = V4L2_CTRL_TYPE_INTEGER,
+		.name =  "",
+		.minimum = 0,
+		.maximum = 1,
+		.step = 1,
+		.default_value = 0,
+		.flags = 0
+	}, {
+	        .id = V4L2_CID_AUTO_EXPOSURE_BIAS,
+		.type = V4L2_CTRL_TYPE_INTEGER,
+		.name =  "",
+		.minimum = -10000,
+		.maximum = 10000,
+		.step = 1,
+		.default_value = 0,
+		.flags = 0
 	},
 };
 
@@ -905,6 +969,7 @@ int v4lcontrol_vidioc_g_ctrl(struct v4lcontrol_data *data, void *arg)
 {
 	int i;
 	struct v4l2_control *ctrl = arg;
+	int res;
 
 	for (i = 0; i < V4LCONTROL_COUNT; i++)
 		if ((data->controls & (1 << i)) &&
@@ -913,8 +978,10 @@ int v4lcontrol_vidioc_g_ctrl(struct v4lcontrol_data *data, void *arg)
 			return 0;
 		}
 
-	return data->dev_ops->ioctl(data->dev_ops_priv, data->fd,
+	res = data->dev_ops->ioctl(data->dev_ops_priv, data->fd,
 			VIDIOC_G_CTRL, arg);
+
+	return res;
 }
 
 static void v4lcontrol_alloc_valid_controls(struct v4lcontrol_data *data,
diff --git a/lib/libv4lconvert/control/libv4lcontrol.h b/lib/libv4lconvert/control/libv4lcontrol.h
index fa9cf42..7a970cb 100644
--- a/lib/libv4lconvert/control/libv4lcontrol.h
+++ b/lib/libv4lconvert/control/libv4lcontrol.h
@@ -45,6 +45,12 @@ enum {
 	V4LCONTROL_AUTO_ENABLE_COUNT,
 	V4LCONTROL_AUTOGAIN,
 	V4LCONTROL_AUTOGAIN_TARGET,
+	V4LCONTROL_AUTO_FOCUS,
+	V4LCONTROL_FOCUS_START,
+	V4LCONTROL_FOCUS_STOP,
+	V4LCONTROL_FOCUS_STATUS,
+	V4LCONTROL_FOCUS_RANGE,
+	V4LCONTROL_EXPOSURE_BIAS,
 	V4LCONTROL_COUNT
 };
 
diff --git a/lib/libv4lconvert/libv4lconvert.c b/lib/libv4lconvert/libv4lconvert.c
index 1a5ccec..e1db987 100644
--- a/lib/libv4lconvert/libv4lconvert.c
+++ b/lib/libv4lconvert/libv4lconvert.c
@@ -1,3 +1,4 @@
+/* -*- c-file-style: "linux" -*- */
 /*
 #             (C) 2008-2011 Hans de Goede <hdegoede@redhat.com>
 
@@ -71,6 +72,8 @@ const struct libv4l_dev_ops *v4lconvert_get_default_dev_ops()
 	return &default_dev_ops;
 }
 
+#define V4LCONVERT_ERR printf
+
 static void v4lconvert_get_framesizes(struct v4lconvert_data *data,
 		unsigned int pixelformat, int index);
 
@@ -89,7 +92,8 @@ static void v4lconvert_get_framesizes(struct v4lconvert_data *data,
 	{ V4L2_PIX_FMT_RGB24,		24,	 1,	 5,	0 }, \
 	{ V4L2_PIX_FMT_BGR24,		24,	 1,	 5,	0 }, \
 	{ V4L2_PIX_FMT_YUV420,		12,	 6,	 1,	0 }, \
-	{ V4L2_PIX_FMT_YVU420,		12,	 6,	 1,	0 }
+	{ V4L2_PIX_FMT_YVU420,		12,	 6,	 1,	0 }, \
+	{ V4L2_PIX_FMT_SGRBG10,		16,	 8,	 8,	0 }
 
 static const struct v4lconvert_pixfmt supported_src_pixfmts[] = {
 	SUPPORTED_DST_PIXFMTS,
@@ -131,7 +135,7 @@ static const struct v4lconvert_pixfmt supported_src_pixfmts[] = {
 	{ V4L2_PIX_FMT_SGBRG8,		 8,	 8,	 8,	0 },
 	{ V4L2_PIX_FMT_SGRBG8,		 8,	 8,	 8,	0 },
 	{ V4L2_PIX_FMT_SRGGB8,		 8,	 8,	 8,	0 },
-	{ V4L2_PIX_FMT_STV0680,		 8,	 8,	 8,	1 },
+	{ V4L2_PIX_FMT_STV0680,		 8,	 8,	 8,	0 },
 	{ V4L2_PIX_FMT_SGRBG10,		16,	 8,	 8,	1 },
 	/* compressed bayer */
 	{ V4L2_PIX_FMT_SPCA561,		 0,	 9,	 9,	1 },
@@ -206,14 +210,16 @@ struct v4lconvert_data *v4lconvert_create_with_dev_ops(int fd, void *dev_ops_pri
 	data->fps = 30;
 
 	/* Check supported formats */
-	for (i = 0; ; i++) {
+	for (i = 0; i < 1; i++) {
 		struct v4l2_fmtdesc fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
 
 		fmt.index = i;
 
 		if (data->dev_ops->ioctl(data->dev_ops_priv, data->fd,
-				VIDIOC_ENUM_FMT, &fmt))
-			break;
+					 VIDIOC_ENUM_FMT, &fmt)) {
+			printf("Enum fmt failed. Assuming N900: SGRBG10\n");
+			fmt.pixelformat = V4L2_PIX_FMT_SGRBG10;
+		}
 
 		for (j = 0; j < ARRAY_SIZE(supported_src_pixfmts); j++)
 			if (fmt.pixelformat == supported_src_pixfmts[j].fmt)
@@ -371,6 +377,7 @@ static int v4lconvert_get_rank(struct v4lconvert_data *data,
 	int needed, rank = 0;
 
 	switch (dest_pixelformat) {
+	case V4L2_PIX_FMT_SGRBG10:		
 	case V4L2_PIX_FMT_RGB24:
 	case V4L2_PIX_FMT_BGR24:
 		rank = supported_src_pixfmts[src_index].rgb_rank;
@@ -525,6 +532,10 @@ static int v4lconvert_do_try_format(struct v4lconvert_data *data,
 void v4lconvert_fixup_fmt(struct v4l2_format *fmt)
 {
 	switch (fmt->fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGRBG10:
+		fmt->fmt.pix.bytesperline = fmt->fmt.pix.width * 2;
+		fmt->fmt.pix.sizeimage = fmt->fmt.pix.width * fmt->fmt.pix.height * 2;
+		break;
 	case V4L2_PIX_FMT_RGB24:
 	case V4L2_PIX_FMT_BGR24:
 		fmt->fmt.pix.bytesperline = fmt->fmt.pix.width * 3;
@@ -687,6 +698,7 @@ static int v4lconvert_processing_needs_double_conversion(
 	case V4L2_PIX_FMT_SGRBG8:
 	case V4L2_PIX_FMT_SRGGB8:
 	case V4L2_PIX_FMT_STV0680:
+	case V4L2_PIX_FMT_SGRBG10:
 		return 0;
 	}
 	switch (dest_pix_fmt) {
@@ -740,6 +752,8 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 	unsigned int height = fmt->fmt.pix.height;
 	unsigned int bytesperline = fmt->fmt.pix.bytesperline;
 
+	//printf("Convert_pixfmt %lx -> %lx\n", src_pix_fmt, dest_pix_fmt);
+	
 	switch (src_pix_fmt) {
 	/* JPG and variants */
 	case V4L2_PIX_FMT_MJPEG:
@@ -866,6 +880,9 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 			v4lconvert_yuv420_to_bgr24(data->convert_pixfmt_buf, dest, width,
 					height, yvu);
 			break;
+		case V4L2_PIX_FMT_SGRBG10:
+			printf("Convert yuv to sgrbg10\n");
+			exit (1);
 		}
 		break;
 	}
@@ -885,6 +902,9 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 		case V4L2_PIX_FMT_YVU420:
 			v4lconvert_hm12_to_yuv420(src, dest, width, height, 1);
 			break;
+		case V4L2_PIX_FMT_SGRBG10:
+			printf("Convert something to sgrbg10\n");
+			exit (1);
 		}
 		break;
 
@@ -903,6 +923,12 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 		unsigned char *tmpbuf;
 		struct v4l2_format tmpfmt = *fmt;
 
+		if (src_pix_fmt == dest_pix_fmt) {
+			int to_copy = MIN(dest_size, src_size);
+			memcpy(dest, src, to_copy);
+			return to_copy;
+		}
+
 		tmpbuf = v4lconvert_alloc_buffer(width * height,
 				&data->convert_pixfmt_buf, &data->convert_pixfmt_buf_size);
 		if (!tmpbuf)
@@ -986,6 +1012,7 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 			V4LCONVERT_ERR("short raw bayer data frame\n");
 			errno = EPIPE;
 			result = -1;
+			/* FIXME: but then we proceed anyway?! */
 		}
 		switch (dest_pix_fmt) {
 		case V4L2_PIX_FMT_RGB24:
@@ -1000,6 +1027,9 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 		case V4L2_PIX_FMT_YVU420:
 			v4lconvert_bayer_to_yuv420(src, dest, width, height, bytesperline, src_pix_fmt, 1);
 			break;
+		case V4L2_PIX_FMT_SGRBG10:
+			printf("Convert bayer to sgrbg10\n");
+			exit(1);
 		}
 		break;
 
@@ -1485,6 +1515,12 @@ int v4lconvert_convert(struct v4lconvert_data *data,
 		temp_needed =
 			my_src_fmt.fmt.pix.width * my_src_fmt.fmt.pix.height * 3 / 2;
 		break;
+	case V4L2_PIX_FMT_SGRBG10:
+		dest_needed =
+			my_dest_fmt.fmt.pix.width * my_dest_fmt.fmt.pix.height * 2;
+		temp_needed =
+			my_src_fmt.fmt.pix.width * my_src_fmt.fmt.pix.height * 2;
+		break;
 	default:
 		V4LCONVERT_ERR("Unknown dest format in conversion\n");
 		errno = EINVAL;
diff --git a/lib/libv4lconvert/processing/autogain.c b/lib/libv4lconvert/processing/autogain.c
index c6866d6..0888697 100644
--- a/lib/libv4lconvert/processing/autogain.c
+++ b/lib/libv4lconvert/processing/autogain.c
@@ -1,3 +1,4 @@
+/* -*- c-file-style: "linux" -*- */
 /*
 #             (C) 2008-2009 Hans de Goede <hdegoede@redhat.com>
 
@@ -21,6 +22,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <math.h>
 
 #include "libv4lprocessing.h"
 #include "libv4lprocessing-priv.h"
@@ -37,6 +39,20 @@ static int autogain_active(struct v4lprocessing_data *data)
 		data->last_gain_correction = 0;
 	}
 
+	/* Related controls:
+
+	   V4L2_CID_EXPOSURE_ABSOLUTE (integer)
+	   V4L2_CID_EXPOSURE_AUTO_PRIORITY
+	   V4L2_CID_EXPOSURE_BIAS ... mEV
+	   V4L2_CID_EXPOSURE_METERING
+
+	   V4L2_CID_ISO_SENSITIVITY
+	   V4L2_CID_ISO_SENSITIVITY_AUTO
+
+	   V4L2_CID_SCENE_MODE
+	   ...sports.
+	*/
+
 	return autogain;
 }
 
@@ -46,6 +62,8 @@ static void autogain_adjust(struct v4l2_queryctrl *ctrl, int *value,
 {
 	int ctrl_range = (ctrl->maximum - ctrl->minimum) / ctrl->step;
 
+	printf("Audogain: adjust\n");
+
 	/* If we are of 3 * deadzone or more, and we have a fine grained
 	   control, take larger steps, otherwise we take ages to get to the
 	   right setting point. We use 256 as tripping point for determining
@@ -68,6 +86,196 @@ static void autogain_adjust(struct v4l2_queryctrl *ctrl, int *value,
 	}
 }
 
+static int get_luminosity_bayer10(uint16_t *buf, const struct v4l2_format *fmt)
+{
+	long long avg_lum = 0;
+	int x, y;
+	
+	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 8 +
+		fmt->fmt.pix.width / 4;
+
+	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
+		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
+			avg_lum += *buf++;
+		buf += fmt->fmt.pix.bytesperline / 2 - fmt->fmt.pix.width / 2;
+	}
+	avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
+	avg_lum /= 4;
+	return avg_lum;
+}
+
+static int get_luminosity_bayer8(unsigned char *buf, const struct v4l2_format *fmt)
+{
+	long long avg_lum = 0;
+	int x, y;
+	
+	buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
+		fmt->fmt.pix.width / 4;
+
+	for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
+		for (x = 0; x < fmt->fmt.pix.width / 2; x++)
+			avg_lum += *buf++;
+		buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
+	}
+	avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
+	return avg_lum;
+}
+
+#define BUCKETS 20
+
+static void v4l2_histogram_bayer10(unsigned short *buf, int cdf[], const struct v4l2_format *fmt)
+{
+    for (int y = 0; y < fmt->fmt.pix.height; y+=19)
+      for (int x = 0; x < fmt->fmt.pix.width; x+=19) {
+	int b;
+	b = buf[fmt->fmt.pix.width*y + x];
+	b = (b * BUCKETS)/(1024);
+	cdf[b]++;
+      }
+}
+
+static int v4l2_s_ctrl(int fd, long id, long value)
+{
+        int res;
+	struct v4l2_control ctrl;
+        ctrl.id = id;
+	ctrl.value = value;
+        res = v4l2_ioctl(fd, VIDIOC_S_CTRL, &ctrl);
+        if (res < 0)
+                printf("Set control %lx %ld failed\n", id, value);
+        return res;
+}
+
+static double get_bias(struct v4lprocessing_data *data)
+{
+	double bias;
+
+	bias = v4lcontrol_get_ctrl(data->control, V4LCONTROL_EXPOSURE_BIAS);
+	printf("Control bias %f\n", bias);
+#if 1
+	bias = bias / 1000;
+	bias = exp2(bias); /* EV -> internal multipliers */
+#endif
+	return bias;
+}
+
+static int v4l2_set_exposure(struct v4lprocessing_data *data, double exposure)
+{
+	double exp, gain; /* microseconds */
+	int exp_, gain_;
+	int fd = data->fd;
+
+	gain = 1;
+	exp = exposure / gain;
+	if (exp > 10000) {
+		exp = 10000;
+		gain = exposure / exp;
+	}
+	if (gain > 16) {
+		gain = 16;
+		exp = exposure / gain;
+	}
+
+	exp_ = exp;
+	gain_ = 10*log(gain)/log(2); 
+	printf("Exposure %f %d, gain %f %d\n", exp, exp_, gain, gain_);
+
+	/* gain | ISO | gain_ */
+	/* 1.   | 100 | 0 */
+	/* 2.   | 200 | 10 */
+
+        /* 16.   | 1600 | 40 */
+			
+	if (v4l2_s_ctrl(fd, 0x00980913 /* FIXME? V4L2_CID_GAIN */, gain_) < 0) {
+		printf("Could not set gain\n");
+	}
+	if (v4l2_s_ctrl(fd, V4L2_CID_EXPOSURE_ABSOLUTE, exp_) < 0) {
+		printf("Could not set exposure\n");
+	}
+	return 0;
+}
+
+struct exposure_data {
+	double exposure;
+};
+
+static int autogain_calculate_lookup_tables_exp(
+		struct v4lprocessing_data *data,
+		unsigned char *buf, const struct v4l2_format *fmt)
+{
+	int cdf[BUCKETS] = { 0, };
+	static struct exposure_data e_data;
+	static struct exposure_data *exp = &e_data;
+
+	v4l2_histogram_bayer10((void *) buf, cdf, fmt);
+
+#if 0
+	printf("hist: ");
+	for (i = 0; i<BUCKETS; i++)
+		printf("%d ", cdf[i]);
+	printf("\n");
+#endif
+	for (int i=1; i<BUCKETS; i++)
+		cdf[i] += cdf[i-1];
+
+	int b = BUCKETS;
+	int brightPixels = cdf[b-1] - cdf[b-8];
+	int targetBrightPixels = cdf[b-1]/50;
+	int maxSaturatedPixels = cdf[b-1]/200;
+	int saturatedPixels = cdf[b-1] - cdf[b-2];
+	// how much should I change brightness by
+	float adjustment = 1.0f;
+#if 0
+	printf( "AutoExposure: totalPixels: %d,"
+		"brightPixels: %d, targetBrightPixels: %d,"
+		"saturatedPixels: %d, maxSaturatedPixels: %d\n",
+		cdf[b-1], brightPixels, targetBrightPixels,
+		saturatedPixels, maxSaturatedPixels);
+#endif
+	  
+	if (saturatedPixels > maxSaturatedPixels) {
+		// first don't let things saturate too much
+		adjustment = 1.0f - ((float)(saturatedPixels - maxSaturatedPixels))/cdf[b-1];
+	} else if (brightPixels < (targetBrightPixels - (saturatedPixels * 4))) {
+		// increase brightness to try and hit the desired number of well exposed pixels
+		int l = b-6;
+		while (brightPixels < targetBrightPixels && l > 0) {
+			brightPixels += cdf[l];
+			brightPixels -= cdf[l-1];
+			l--;
+		}
+
+		// that level is supposed to be at b-11;
+		adjustment = ((float) (b-6+1))/(l+1);
+	} else {
+		// we're not oversaturated, and we have enough bright pixels. Do nothing.
+	}
+
+	{
+		float limit = 4;
+		if (adjustment > limit) { adjustment = limit; }
+		if (adjustment < 1/limit) { adjustment = 1/limit; }
+	}
+	adjustment *= get_bias(data);
+	  
+	exp->exposure *= adjustment;
+	if (exp->exposure < 1)
+		exp->exposure = 1;
+	{
+		float limit = 64000000;
+		if (exp->exposure > limit)
+			exp->exposure = limit;
+	}
+	
+	if (adjustment != 1.)
+		printf( "AutoExposure: adjustment: %f exposure %f\n", adjustment, exp->exposure);
+
+	v4l2_set_exposure(data, exp->exposure);
+	return 0;
+}
+
+/* This autogain version is suitable for webcams with linear controls, not for cameras */
+
 /* auto gain and exposure algorithm based on the knee algorithm described here:
 http://ytse.tricolour.net/docs/LowLightOptimization.html */
 static int autogain_calculate_lookup_tables(
@@ -80,11 +288,17 @@ static int autogain_calculate_lookup_tables(
 	struct v4l2_queryctrl gainctrl, expoctrl;
 	const int deadzone = 6;
 
+	printf("autogain: calculate lookups\n");
+
 	ctrl.id = V4L2_CID_EXPOSURE;
 	expoctrl.id = V4L2_CID_EXPOSURE;
-	if (SYS_IOCTL(data->fd, VIDIOC_QUERYCTRL, &expoctrl) ||
-			SYS_IOCTL(data->fd, VIDIOC_G_CTRL, &ctrl))
-		return 0;
+	if (v4l2_ioctl(data->fd, VIDIOC_QUERYCTRL, &expoctrl) ||
+	    v4l2_ioctl(data->fd, VIDIOC_G_CTRL, &ctrl)) {
+		/* No exposure control; but perhaps this is digital camera,
+		   we have V4L2_CID_EXPOSURE_ABSOLUTE, and should use different
+		   control algorithm. */
+		return autogain_calculate_lookup_tables_exp(data, buf, fmt);
+	}
 
 	exposure = orig_exposure = ctrl.value;
 	/* Determine a value below which we try to not lower the exposure,
@@ -100,25 +314,26 @@ static int autogain_calculate_lookup_tables(
 
 	ctrl.id = V4L2_CID_GAIN;
 	gainctrl.id = V4L2_CID_GAIN;
-	if (SYS_IOCTL(data->fd, VIDIOC_QUERYCTRL, &gainctrl) ||
-			SYS_IOCTL(data->fd, VIDIOC_G_CTRL, &ctrl))
+	if (v4l2_ioctl(data->fd, VIDIOC_QUERYCTRL, &gainctrl) ||
+	    v4l2_ioctl(data->fd, VIDIOC_G_CTRL, &ctrl))
 		return 0;
 	gain = orig_gain = ctrl.value;
 
+	printf("Looking at pixels...\n");
+
 	switch (fmt->fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGBRG10:
+	case V4L2_PIX_FMT_SGRBG10:
+	case V4L2_PIX_FMT_SBGGR10:
+	case V4L2_PIX_FMT_SRGGB10:
+		avg_lum = get_luminosity_bayer10((void *) buf, fmt);
+		break;
+
 	case V4L2_PIX_FMT_SGBRG8:
 	case V4L2_PIX_FMT_SGRBG8:
 	case V4L2_PIX_FMT_SBGGR8:
 	case V4L2_PIX_FMT_SRGGB8:
-		buf += fmt->fmt.pix.height * fmt->fmt.pix.bytesperline / 4 +
-			fmt->fmt.pix.width / 4;
-
-		for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
-			for (x = 0; x < fmt->fmt.pix.width / 2; x++)
-				avg_lum += *buf++;
-			buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width / 2;
-		}
-		avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width / 4;
+		avg_lum = get_luminosity_bayer8(buf, fmt);
 		break;
 
 	case V4L2_PIX_FMT_RGB24:
@@ -137,7 +352,7 @@ static int autogain_calculate_lookup_tables(
 		avg_lum /= fmt->fmt.pix.height * fmt->fmt.pix.width * 3 / 4;
 		break;
 	}
-
+	
 	/* If we are off a multiple of deadzone, do multiple steps to reach the
 	   desired lumination fast (with the risc of a slight overshoot) */
 	target = v4lcontrol_get_ctrl(data->control, V4LCONTROL_AUTOGAIN_TARGET);
@@ -199,20 +414,23 @@ static int autogain_calculate_lookup_tables(
 		data->lookup_table_update_counter = V4L2PROCESSING_UPDATE_RATE - 2;
 	}
 
+	printf("Setting gain %d / exposure %d\n", gain, exposure);
+
 	if (gain != orig_gain) {
 		ctrl.id = V4L2_CID_GAIN;
 		ctrl.value = gain;
-		SYS_IOCTL(data->fd, VIDIOC_S_CTRL, &ctrl);
+		v4l2_ioctl(data->fd, VIDIOC_S_CTRL, &ctrl);
 	}
 	if (exposure != orig_exposure) {
-		ctrl.id = V4L2_CID_EXPOSURE;
+		ctrl.id = V4L2_CID_EXPOSURE_ABSOLUTE;
 		ctrl.value = exposure;
-		SYS_IOCTL(data->fd, VIDIOC_S_CTRL, &ctrl);
+		v4l2_ioctl(data->fd, VIDIOC_S_CTRL, &ctrl);
 	}
 
 	return 0;
 }
 
 struct v4lprocessing_filter autogain_filter = {
-	autogain_active, autogain_calculate_lookup_tables
+	autogain_active, autogain_calculate_lookup_tables_exp
 };
+
diff --git a/lib/libv4lconvert/processing/libv4lprocessing-priv.h b/lib/libv4lconvert/processing/libv4lprocessing-priv.h
index e4a29dd..43badef 100644
--- a/lib/libv4lconvert/processing/libv4lprocessing-priv.h
+++ b/lib/libv4lconvert/processing/libv4lprocessing-priv.h
@@ -24,7 +24,9 @@
 #include "../control/libv4lcontrol.h"
 #include "../libv4lsyscall-priv.h"
 
-#define V4L2PROCESSING_UPDATE_RATE 10
+#define V4L2PROCESSING_UPDATE_RATE 1
+/* Size of lookup tables */
+#define LSIZE 1024
 
 struct v4lprocessing_data {
 	struct v4lcontrol_data *control;
@@ -32,15 +34,15 @@ struct v4lprocessing_data {
 	int do_process;
 	int controls_changed;
 	/* True if any of the lookup tables does not contain
-	   linear 0-255 */
+	   linear 0..LSIZE-1 */
 	int lookup_table_active;
 	/* Counts the number of processed frames until a
 	   V4L2PROCESSING_UPDATE_RATE overflow happens */
 	int lookup_table_update_counter;
 	/* RGB/BGR lookup tables */
-	unsigned char comp1[256];
-	unsigned char green[256];
-	unsigned char comp2[256];
+	unsigned short comp1[LSIZE];
+	unsigned short green[LSIZE];
+	unsigned short comp2[LSIZE];
 	/* Filter private data for filters which need it */
 	/* whitebalance.c data */
 	int green_avg;
@@ -48,7 +50,7 @@ struct v4lprocessing_data {
 	int comp2_avg;
 	/* gamma.c data */
 	int last_gamma;
-	unsigned char gamma_table[256];
+	unsigned char gamma_table[LSIZE];
 	/* autogain.c data */
 	int last_gain_correction;
 };
@@ -64,5 +66,6 @@ struct v4lprocessing_filter {
 extern struct v4lprocessing_filter whitebalance_filter;
 extern struct v4lprocessing_filter autogain_filter;
 extern struct v4lprocessing_filter gamma_filter;
+extern struct v4lprocessing_filter focus_filter;
 
 #endif
diff --git a/lib/libv4lconvert/processing/libv4lprocessing.c b/lib/libv4lconvert/processing/libv4lprocessing.c
index b061f50..b66c15a 100644
--- a/lib/libv4lconvert/processing/libv4lprocessing.c
+++ b/lib/libv4lconvert/processing/libv4lprocessing.c
@@ -31,6 +31,7 @@ static struct v4lprocessing_filter *filters[] = {
 	&whitebalance_filter,
 	&autogain_filter,
 	&gamma_filter,
+	&focus_filter,
 };
 
 struct v4lprocessing_data *v4lprocessing_create(int fd, struct v4lcontrol_data *control)
@@ -74,7 +75,7 @@ static void v4lprocessing_update_lookup_tables(struct v4lprocessing_data *data,
 {
 	int i;
 
-	for (i = 0; i < 256; i++) {
+	for (i = 0; i < LSIZE; i++) {
 		data->comp1[i] = i;
 		data->green[i] = i;
 		data->comp2[i] = i;
@@ -89,15 +90,34 @@ static void v4lprocessing_update_lookup_tables(struct v4lprocessing_data *data,
 	}
 }
 
-static void v4lprocessing_do_processing(struct v4lprocessing_data *data,
-		unsigned char *buf, const struct v4l2_format *fmt)
+static void v4lprocessing_do_processing_bayer10(struct v4lprocessing_data *data,
+		unsigned short *buf, const struct v4l2_format *fmt)
 {
 	int x, y;
+  		for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
+			for (x = 0; x < fmt->fmt.pix.width / 2; x++) {
+				*buf = data->green[*buf];
+				buf++;
+				*buf = data->comp1[*buf];
+				buf++;
+			}
+			buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width * 2;
+			for (x = 0; x < fmt->fmt.pix.width / 2; x++) {
+				*buf = data->comp2[*buf];
+				buf++;
+				*buf = data->green[*buf];
+				buf++;
+			}
+			buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width * 2;;
+		}
 
-	switch (fmt->fmt.pix.pixelformat) {
-	case V4L2_PIX_FMT_SGBRG8:
-	case V4L2_PIX_FMT_SGRBG8: /* Bayer patterns starting with green */
-		for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
+}
+
+static void v4lprocessing_do_processing_bayer8(struct v4lprocessing_data *data,
+		unsigned char *buf, const struct v4l2_format *fmt)
+{
+	int x, y;
+  		for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
 			for (x = 0; x < fmt->fmt.pix.width / 2; x++) {
 				*buf = data->green[*buf];
 				buf++;
@@ -113,8 +133,25 @@ static void v4lprocessing_do_processing(struct v4lprocessing_data *data,
 			}
 			buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width;
 		}
+
+}
+
+static void v4lprocessing_do_processing(struct v4lprocessing_data *data,
+		unsigned char *buf, const struct v4l2_format *fmt)
+{
+	int x, y;
+
+	switch (fmt->fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGRBG10: /* Bayer patterns starting with green */
+	  	v4lprocessing_do_processing_bayer10(data, buf, fmt);
 		break;
 
+	case V4L2_PIX_FMT_SGBRG8:
+	case V4L2_PIX_FMT_SGRBG8: /* Bayer patterns starting with green */
+	  	v4lprocessing_do_processing_bayer8(data, buf, fmt);
+		break;
+
+
 	case V4L2_PIX_FMT_SBGGR8:
 	case V4L2_PIX_FMT_SRGGB8: /* Bayer patterns *NOT* starting with green */
 		for (y = 0; y < fmt->fmt.pix.height / 2; y++) {
@@ -164,15 +201,20 @@ void v4lprocessing_processing(struct v4lprocessing_data *data,
 	case V4L2_PIX_FMT_SGRBG8:
 	case V4L2_PIX_FMT_SBGGR8:
 	case V4L2_PIX_FMT_SRGGB8:
+	case V4L2_PIX_FMT_SGBRG10:
+	case V4L2_PIX_FMT_SGRBG10:
+	case V4L2_PIX_FMT_SBGGR10:
+	case V4L2_PIX_FMT_SRGGB10:
 	case V4L2_PIX_FMT_RGB24:
 	case V4L2_PIX_FMT_BGR24:
 		break;
 	default:
-		return; /* Non supported pix format */
+		printf("Processing: unsupported pix format\n");
+		break; /* Non supported pix format */
 	}
 
 	if (data->controls_changed ||
-			data->lookup_table_update_counter == V4L2PROCESSING_UPDATE_RATE) {
+			data->lookup_table_update_counter >= V4L2PROCESSING_UPDATE_RATE) {
 		data->controls_changed = 0;
 		data->lookup_table_update_counter = 0;
 		/* Do this after resetting lookup_table_update_counter so that filters can
@@ -181,8 +223,9 @@ void v4lprocessing_processing(struct v4lprocessing_data *data,
 	} else
 		data->lookup_table_update_counter++;
 
-	if (data->lookup_table_active)
+	if (data->lookup_table_active) {
 		v4lprocessing_do_processing(data, buf, fmt);
+	}
 
 	data->do_process = 0;
 }
diff --git a/lib/libv4lconvert/processing/whitebalance.c b/lib/libv4lconvert/processing/whitebalance.c
index c74069a..95eb9c7 100644
--- a/lib/libv4lconvert/processing/whitebalance.c
+++ b/lib/libv4lconvert/processing/whitebalance.c
@@ -27,8 +27,8 @@
 #include "libv4lprocessing-priv.h"
 #include "../libv4lconvert-priv.h" /* for PIX_FMT defines */
 
-#define CLIP256(color) (((color) > 0xff) ? 0xff : (((color) < 0) ? 0 : (color)))
 #define CLIP(color, min, max) (((color) > (max)) ? (max) : (((color) < (min)) ? (min) : (color)))
+#define CLIPLSIZE(color) CLIP(color, 0, LSIZE-1)
 
 static int whitebalance_active(struct v4lprocessing_data *data)
 {
@@ -43,6 +43,7 @@ static int whitebalance_active(struct v4lprocessing_data *data)
 	return wb;
 }
 
+/* Updates data->comp1/comp2 tables, that are later used by v4lprocessing_do_processing() */
 static int whitebalance_calculate_lookup_tables_generic(
 		struct v4lprocessing_data *data, int green_avg, int comp1_avg, int comp2_avg)
 {
@@ -51,12 +52,12 @@ static int whitebalance_calculate_lookup_tables_generic(
 	const int max_step = 128;
 
 	/* Clip averages (restricts maximum white balance correction) */
-	green_avg = CLIP(green_avg, 512, 3072);
-	comp1_avg = CLIP(comp1_avg, 512, 3072);
-	comp2_avg = CLIP(comp2_avg, 512, 3072);
+	green_avg = CLIP(green_avg, LSIZE*2, LSIZE*12);
+	comp1_avg = CLIP(comp1_avg, LSIZE*2, LSIZE*12);
+	comp2_avg = CLIP(comp2_avg, LSIZE*2, LSIZE*12);
 
 	/* First frame ? */
-	if (data->green_avg == 0) {
+	if (1 || data->green_avg == 0) {
 		data->green_avg = green_avg;
 		data->comp1_avg = comp1_avg;
 		data->comp2_avg = comp2_avg;
@@ -111,15 +112,54 @@ static int whitebalance_calculate_lookup_tables_generic(
 
 	avg_avg = (data->green_avg + data->comp1_avg + data->comp2_avg) / 3;
 
-	for (i = 0; i < 256; i++) {
-		data->comp1[i] = CLIP256(data->comp1[i] * avg_avg / data->comp1_avg);
-		data->green[i] = CLIP256(data->green[i] * avg_avg / data->green_avg);
-		data->comp2[i] = CLIP256(data->comp2[i] * avg_avg / data->comp2_avg);
+	for (i = 0; i < LSIZE; i++) {
+		data->comp1[i] = CLIPLSIZE(data->comp1[i] * avg_avg / data->comp1_avg);
+		data->green[i] = CLIPLSIZE(data->green[i] * avg_avg / data->green_avg);
+		data->comp2[i] = CLIPLSIZE(data->comp2[i] * avg_avg / data->comp2_avg);
 	}
 
 	return 1;
 }
 
+static int whitebalance_calculate_lookup_tables_bayer10(
+		struct v4lprocessing_data *data, unsigned short *buf,
+		const struct v4l2_format *fmt, int starts_with_green)
+{
+	int x, y, a1 = 0, a2 = 0, b1 = 0, b2 = 0;
+	int green_avg, comp1_avg, comp2_avg;
+
+	for (y = 0; y < fmt->fmt.pix.height; y += 2) {
+		for (x = 0; x < fmt->fmt.pix.width; x += 2) {
+			a1 += *buf++;
+			a2 += *buf++;
+		}
+		buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width * 2;
+		for (x = 0; x < fmt->fmt.pix.width; x += 2) {
+			b1 += *buf++;
+			b2 += *buf++;
+		}
+		buf += fmt->fmt.pix.bytesperline - fmt->fmt.pix.width * 2;
+	}
+
+	if (starts_with_green) {
+		green_avg = a1 / 2 + b2 / 2;
+		comp1_avg = a2;
+		comp2_avg = b1;
+	} else {
+		green_avg = a2 / 2 + b1 / 2;
+		comp1_avg = a1;
+		comp2_avg = b2;
+	}
+
+	/* Norm avg to ~ 0 - 4095 */
+	green_avg /= fmt->fmt.pix.width * fmt->fmt.pix.height / 64;
+	comp1_avg /= fmt->fmt.pix.width * fmt->fmt.pix.height / 64;
+	comp2_avg /= fmt->fmt.pix.width * fmt->fmt.pix.height / 64;
+
+	return whitebalance_calculate_lookup_tables_generic(data, green_avg,
+			comp1_avg, comp2_avg);
+}
+
 static int whitebalance_calculate_lookup_tables_bayer(
 		struct v4lprocessing_data *data, unsigned char *buf,
 		const struct v4l2_format *fmt, int starts_with_green)
@@ -189,6 +229,9 @@ static int whitebalance_calculate_lookup_tables(
 		unsigned char *buf, const struct v4l2_format *fmt)
 {
 	switch (fmt->fmt.pix.pixelformat) {
+	case V4L2_PIX_FMT_SGRBG10: /* Bayer patterns starting with green */
+		return whitebalance_calculate_lookup_tables_bayer10(data, (void *) buf, fmt, 1);
+
 	case V4L2_PIX_FMT_SGBRG8:
 	case V4L2_PIX_FMT_SGRBG8: /* Bayer patterns starting with green */
 		return whitebalance_calculate_lookup_tables_bayer(data, buf, fmt, 1);
@@ -200,6 +243,9 @@ static int whitebalance_calculate_lookup_tables(
 	case V4L2_PIX_FMT_RGB24:
 	case V4L2_PIX_FMT_BGR24:
 		return whitebalance_calculate_lookup_tables_rgb(data, buf, fmt);
+
+	default:
+	        printf("Whitebalance: unknown format\n");
 	}
 
 	return 0; /* Should never happen */


-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: Camera support, Prague next week, sdlcam

[Hans Verkuil]

On 22/10/17 00:00, Pavel Machek wrote:
> Hi!
> 
> I'd still like to get some reasonable support for cellphone camera in
> Linux.
> 
> IMO first reasonable step is to merge sdlcam, then we can implement
> autofocus, improve autogain... and rest of the boring stuff. Ouch and
> media graph support would be nice. Currently, _nothing_ works with
> media graph device, such as N900.

Can you post your latest rebased patch for sdlcam for v4l-utils?

I'll do a review and will likely merge it for you. Yes, I've changed my
mind on that.

> 
> I'll talk about the issues at ELCE in few days:
> 
> https://osseu17.sched.com/event/ByYH/cheap-complex-cameras-pavel-machek-denx-software-engineering-gmbh
> 
> Will someone else be there? Is there some place where v4l people meet?

Why don't we discuss this Tuesday morning at 9am? I have no interest in the
keynotes on that day, so those who are interested can get together.

I'll be at your presentation tomorrow and we can discuss a bit during
the following coffee break if time permits.

Regards,

	Hans

Re: Camera support, Prague next week, sdlcam

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 1312 bytes --]

Hi!

> > I'd still like to get some reasonable support for cellphone camera in
> > Linux.
> > 
> > IMO first reasonable step is to merge sdlcam, then we can implement
> > autofocus, improve autogain... and rest of the boring stuff. Ouch and
> > media graph support would be nice. Currently, _nothing_ works with
> > media graph device, such as N900.
> 
> Can you post your latest rebased patch for sdlcam for v4l-utils?
> 
> I'll do a review and will likely merge it for you. Yes, I've changed my
> mind on that.

Ok, will do, thanks!

> > I'll talk about the issues at ELCE in few days:
> > 
> > https://osseu17.sched.com/event/ByYH/cheap-complex-cameras-pavel-machek-denx-software-engineering-gmbh
> > 
> > Will someone else be there? Is there some place where v4l people meet?
> 
> Why don't we discuss this Tuesday morning at 9am? I have no interest in the
> keynotes on that day, so those who are interested can get together.
> 
> I'll be at your presentation tomorrow and we can discuss a bit during
> the following coffee break if time permits.

Ok, sounds like a plan. Lets confirm Tuesday morning tommorow.

Thanks,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: Camera support, Prague next week, sdlcam

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 687 bytes --]

Hi!

> > I'll talk about the issues at ELCE in few days:
> > 
> > https://osseu17.sched.com/event/ByYH/cheap-complex-cameras-pavel-machek-denx-software-engineering-gmbh
> > 
> > Will someone else be there? Is there some place where v4l people meet?
> 
> Why don't we discuss this Tuesday morning at 9am? I have no interest in the
> keynotes on that day, so those who are interested can get together.

Ok, what about 9:30am? The place near the elevators where we were
talking last time?

And.... sorry for late reply.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: Camera support, Prague next week, sdlcam

[Hans Verkuil]

Sounds good. That's the elevators on level LL by the way.

Regards,

Hans

On October 23, 2017 8:54:49 PM GMT+02:00, Pavel Machek <pavel@ucw.cz> wrote:
>Hi!
>
>> > I'll talk about the issues at ELCE in few days:
>> > 
>> >
>https://osseu17.sched.com/event/ByYH/cheap-complex-cameras-pavel-machek-denx-software-engineering-gmbh
>> > 
>> > Will someone else be there? Is there some place where v4l people
>meet?
>> 
>> Why don't we discuss this Tuesday morning at 9am? I have no interest
>in the
>> keynotes on that day, so those who are interested can get together.
>
>Ok, what about 9:30am? The place near the elevators where we were
>talking last time?
>
>And.... sorry for late reply.
>									Pavel

-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Re: Camera support, Prague next week, sdlcam

[Sakari Ailus]

On Mon, Oct 23, 2017 at 09:24:24PM +0200, Hans Verkuil wrote:
> Sounds good. That's the elevators on level LL by the way.

I'll be there, too!

-- 
Sakari Ailus
e-mail: sakari.ailus@iki.fi

Re: Camera support, Prague next week, sdlcam

[Mauro Carvalho Chehab]

Em Mon, 23 Oct 2017 23:15:57 +0300
Sakari Ailus <sakari.ailus@iki.fi> escreveu:

> On Mon, Oct 23, 2017 at 09:24:24PM +0200, Hans Verkuil wrote:
> > Sounds good. That's the elevators on level LL by the way.  
> 
> I'll be there, too!
> 

I'll try to join you there too.


Cheers,
Mauro

Nokia N9: fun with camera

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 2484 bytes --]

Hi!

Sakari, I am actually playing with N9 camera, not N950. That comes
next.

And the clock error I mentioned ... seems to be
-EPROBE_DEFER. So... not an issue.

Strange thing is, that my sensors seems to have different resolution
from yours:

- entity 89: smiapp pixel_array 1-0010 (1 pad, 1 link)
             type V4L2 subdev subtype Sensor flags 0
	                  device node name /dev/v4l-subdev9
		          pad0: Source [fmt:SRGGB10_1X10/3572x2464 field:none
	                      crop.bounds:(0,0)/3572x2464 crop:(0,0)/3572x2464]
 ->
             "smiapp binner 1-0010":0 [ENABLED,IMMUTABLE]

(And you mentioned width 3600, and SGRBG10).

I updated my scripts accordingly. Now I get

pavel@n900:~/g/tui/camera$ /my/tui/yavta/yavta -c5 -f SRGGB10
-F/tmp/foo -s 3572x2464 /dev/video1
Device /dev/video1 opened.
Device `OMAP3 ISP CSI2a output' on `media' is a video capture (without
mplanes) device.
Video format set: SRGGB10 (30314752) 3572x2464 (stride 7144) field
none buffer size 17602816
Video format: SRGGB10 (30314752) 3572x2464 (stride 7144) field none
buffer size 17602816
2 buffers requested.
length: 17602816 offset: 0 timestamp type/source: mono/EoF
Buffer 0/0 mapped at address 0xb5cb1000.
length: 17602816 offset: 17604608 timestamp type/source: mono/EoF
Buffer 1/0 mapped at address 0xb4be7000.

...but here it hangs. (Kernel v4.13).

dmesg says:

[ 2862.229736] smiapp 1-0010: flip 0
[ 2862.229766] smiapp 1-0010: new pixel order RGGB
[ 2862.233764] smiapp 1-0010: 0x00021700 "min_frame_length_lines_bin"
= 166, 0xa6
[ 2862.234558] smiapp 1-0010: 0x00021702 "max_frame_length_lines_bin"
= 65535, 0xffff
[ 2862.235351] smiapp 1-0010: 0x00021704 "min_line_length_pck_bin" =
3812, 0xee4
[ 2862.236114] smiapp 1-0010: 0x00021706 "max_line_length_pck_bin" =
32752, 0x7ff0
[ 2862.238067] smiapp 1-0010: 0x00021708 "min_line_blanking_pck_bin" =
240, 0xf0
[ 2862.240844] smiapp 1-0010: 0x0002170a
"fine_integration_time_min_bin" = 0, 0x0
[ 2862.242553] smiapp 1-0010: 0x0002170c
"fine_integration_time_max_margin_bin" = 0, 0x0
[ 2862.242614] smiapp 1-0010: vblank   	 26
[ 2862.242645] smiapp 1-0010: hblank		240
[ 2862.242675] smiapp 1-0010: real timeperframe	100/839

I did some more experiments, but could not grab a frame.

Best regards,
									Pavel


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(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: Nokia N9: fun with camera

[Pavel Machek]

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Hi!

> Sakari, I am actually playing with N9 camera, not N950. That comes
> next.
> 
> And the clock error I mentioned ... seems to be
> -EPROBE_DEFER. So... not an issue.

Hmm, and with similar config, I got N950 to work. ... which should
give me enough clues to get N9 to work. I guess I forgot to reset the
pipeline between the tries, or something.

For the record, this got me some data on n950:

 m.media_ctl( [ '-f', '"OMAP3 ISP CSI2a":0 [fmt:%s/%dx%d]' % (m.fmt, m.cap_x, m.cap_y) ] )
 m.media_ctl( [ '-l', '"OMAP3 ISP CSI2a":1 -> "OMAP3 ISP CSI2a output":0[1]' ] )

 # WORKS!!!!
 # pavel@n900:~/g/tui/camera$ sudo /my/tui/yavta/yavta
 # --capture=8 --skip 0 --format SGRBG10 --size 4272x3016 /dev/video1 --file=/tmp/delme#

...ouch. It only worked twice :-(. Either driver gets confused by my
attempts, or it relied on some other initialization code. Strange.

Best regards,
									Pavel

-- 
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(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: Nokia N9: fun with camera

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 2629 bytes --]

Hi!

> > Sakari, I am actually playing with N9 camera, not N950. That comes
> > next.
> > 
> > And the clock error I mentioned ... seems to be
> > -EPROBE_DEFER. So... not an issue.
> 
> Hmm, and with similar config, I got N950 to work. ... which should
> give me enough clues to get N9 to work. I guess I forgot to reset the
> pipeline between the tries, or something.
> 
> For the record, this got me some data on n950:
> 
>  m.media_ctl( [ '-f', '"OMAP3 ISP CSI2a":0 [fmt:%s/%dx%d]' % (m.fmt, m.cap_x, m.cap_y) ] )
>  m.media_ctl( [ '-l', '"OMAP3 ISP CSI2a":1 -> "OMAP3 ISP CSI2a output":0[1]' ] )
> 
>  # WORKS!!!!
>  # pavel@n900:~/g/tui/camera$ sudo /my/tui/yavta/yavta
>  # --capture=8 --skip 0 --format SGRBG10 --size 4272x3016 /dev/video1 --file=/tmp/delme#
> 
> ...ouch. It only worked twice :-(. Either driver gets confused by my
> attempts, or it relied on some other initialization code. Strange.

Hmm, so it works "reliably" after boot. But it also locks up machine
with high probability. If you have N950, it might still be handy...

Messages are:

['-r']
['-f', '"OMAP3 ISP CSI2a":0 [fmt:SGRBG10/4272x3016]']
Warning: the -f option is deprecated and has been replaced by -V.
['-l', '"OMAP3 ISP CSI2a":1 -> "OMAP3 ISP CSI2a output":0[1]']
Testing: is raw
Testing:  /my/tui/yavta/yavta --capture=8 --skip 0 --format SGRBG10
--size 4272x3016 /dev/video_sensor --file=/tmp/delme#
Error opening device /dev/video_sensor: Permission denied (13).
Raw mode is  1
Raw mode is  1
Testing: is raw
Testing:  /my/tui/yavta/yavta --capture=8 --skip 0 --format SGRBG10
--size 4272x3016 /dev/video_sensor --file=/tmp/delme#
Device /dev/video_sensor opened.
Device `OMAP3 ISP CSI2a output' on `media' is a video capture (without
mplanes) device.
Video format set: SGRBG10 (30314142) 4272x3016 (stride 8544) field
none buffer size 25768704
Video format: SGRBG10 (30314142) 4272x3016 (stride 8544) field none
buffer size 25768704
1 buffers requested.
length: 25768704 offset: 0 timestamp type/source: mono/EoF
Buffer 0/0 mapped at address 0xb54e9000.
0 (0) [-] none 0 25768704 B 691.756907 691.758403 6.212 fps ts
mono/EoF
1 (0) [-] none 1 25768704 B 694.821025 694.821422 0.326 fps ts
mono/EoF
2 (0) [E] none 2 25768704 B 698.530833 698.534739 0.270 fps ts
mono/EoF
3 (0) [-] none 3 25768704 B 700.788127 700.790996 0.443 fps ts
mono/EoF
(and here it locked up :-(. Sometimes it captures more.)

Thanks,

								Pavel




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(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: support autofocus / autogain in libv4l2

[Pavel Machek]

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Hi!

> Please don't add a new application under lib/. It is fine if you want
> some testing application, if the ones there aren't enough, but please
> place it under contrib/test/.
> 
> You should likely take a look at v4l2grab first, as it could have
> almost everything you would need.

I really need some kind of video output. v4l2grab is not useful
there. v4l2gl might be, but I don't think I have enough dependencies.

Umm, and it looks like libv4l can not automatically convert from
GRBG10.. and if it could, going through RGB24 would probably be too
slow on this device :-(.

> IMO, the above belongs to a separate processing module under
> 	lib/libv4lconvert/processing/

Is there an example using autogain/autowhitebalance from
libv4lconvert?

Best regards,
									Pavel
-- 
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(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: support autofocus / autogain in libv4l2

[Mauro Carvalho Chehab]

Em Tue, 25 Apr 2017 00:07:01 +0200
Pavel Machek <pavel@ucw.cz> escreveu:

> Hi!
> 
> > Please don't add a new application under lib/. It is fine if you want
> > some testing application, if the ones there aren't enough, but please
> > place it under contrib/test/.
> > 
> > You should likely take a look at v4l2grab first, as it could have
> > almost everything you would need.  
> 
> I really need some kind of video output. v4l2grab is not useful
> there. v4l2gl might be, but I don't think I have enough dependencies.

Well, you could use some app to show the snaps that v4l2grab takes.

Yeah, compiling v4l2gl on N9 can indeed be complex. I suspect that it 
shouldn't hard to compile xawtv there (probably disabling some optional
features).

> Umm, and it looks like libv4l can not automatically convert from
> GRBG10.. and if it could, going through RGB24 would probably be too
> slow on this device :-(.

I suspect it shouldn't be hard to add support for GRBG10. It already
supports 8 and 16 bits Bayer formats, at lib/libv4lconvert/bayer.c
(to both RGB and YUV formats).

How it would preform is another question ;)

> > IMO, the above belongs to a separate processing module under
> > 	lib/libv4lconvert/processing/  
> 
> Is there an example using autogain/autowhitebalance from
> libv4lconvert?

Well, if you plug a USB camera without those controls, it should
automatically expose controls for it, as if the device had such
controls.

Thanks,
Mauro

Re: support autofocus / autogain in libv4l2

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 1919 bytes --]

Hi!

> > > Please don't add a new application under lib/. It is fine if you want
> > > some testing application, if the ones there aren't enough, but please
> > > place it under contrib/test/.
> > > 
> > > You should likely take a look at v4l2grab first, as it could have
> > > almost everything you would need.  
> > 
> > I really need some kind of video output. v4l2grab is not useful
> > there. v4l2gl might be, but I don't think I have enough dependencies.
> 
> Well, you could use some app to show the snaps that v4l2grab takes.

That would be too slow :-(.

> Yeah, compiling v4l2gl on N9 can indeed be complex. I suspect that it 
> shouldn't hard to compile xawtv there (probably disabling some optional
> features).

I do have mplayer working, but that one is not linked against libv4l2
:-(.

> > Umm, and it looks like libv4l can not automatically convert from
> > GRBG10.. and if it could, going through RGB24 would probably be too
> > slow on this device :-(.
> 
> I suspect it shouldn't be hard to add support for GRBG10. It already
> supports 8 and 16 bits Bayer formats, at lib/libv4lconvert/bayer.c
> (to both RGB and YUV formats).

Is 16bit bayer a recent development? I can't see it in

commit 374806e868f5a7a48ecffde4c6a1abfcfa5ccd65
Author: Hans Verkuil <hans.verkuil@cisco.com>
Date:   Fri Apr 22 09:31:57 2016 +0200

> > Is there an example using autogain/autowhitebalance from
> > libv4lconvert?
> 
> Well, if you plug a USB camera without those controls, it should
> automatically expose controls for it, as if the device had such
> controls.

And settings are persistent, so I can enable autogain, then lauch
something like xawtv, and it will automatically get autogain? Ok,
good.

Regards,
									Pavel
-- 
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(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: support autofocus / autogain in libv4l2

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 3230 bytes --]

Hi!

> > Umm, and it looks like libv4l can not automatically convert from
> > GRBG10.. and if it could, going through RGB24 would probably be too
> > slow on this device :-(.
> 
> I suspect it shouldn't be hard to add support for GRBG10. It already
> supports 8 and 16 bits Bayer formats, at lib/libv4lconvert/bayer.c
> (to both RGB and YUV formats).

Proper format for 16 bit bayer would be tricky, AFAICT. Anyway, does
this look reasonable? It does not work too well here, since omap3isp
driver does not seem to support ENUM_FMT. (And I get just half of the
vertical image, strange. Interlacing?)

Best regards,
								Pavel

diff --git a/lib/libv4lconvert/libv4lconvert.c b/lib/libv4lconvert/libv4lconvert.c
index d3d8936..2a469b2 100644
--- a/lib/libv4lconvert/libv4lconvert.c
+++ b/lib/libv4lconvert/libv4lconvert.c
@@ -123,6 +126,8 @@ static const struct v4lconvert_pixfmt supported_src_pixfmts[] = {
 	{ V4L2_PIX_FMT_SGRBG8,		 8,	 8,	 8,	1 },
 	{ V4L2_PIX_FMT_SRGGB8,		 8,	 8,	 8,	1 },
 	{ V4L2_PIX_FMT_STV0680,		 8,	 8,	 8,	1 },
+
+	{ V4L2_PIX_FMT_SGRBG10,		16,	 8,	 8,	1 },
 	/* compressed bayer */
 	{ V4L2_PIX_FMT_SPCA561,		 0,	 9,	 9,	1 },
 	{ V4L2_PIX_FMT_SN9C10X,		 0,	 9,	 9,	1 },
@@ -668,6 +680,7 @@ static int v4lconvert_processing_needs_double_conversion(
 	case V4L2_PIX_FMT_SGRBG8:
 	case V4L2_PIX_FMT_SRGGB8:
 	case V4L2_PIX_FMT_STV0680:
+	case V4L2_PIX_FMT_SGRBG10:
 		return 0;
 	}
 	switch (dest_pix_fmt) {
@@ -694,6 +707,17 @@ unsigned char *v4lconvert_alloc_buffer(int needed,
 	return *buf;
 }
 
+static void v4lconvert_10to8(void *_src, unsigned char *dst, int width, int height)
+{
+	int i;
+	uint16_t *src = _src;
+	
+	printf("sizes %d x %d\n", width, height);
+	for (i=0; i<width*height; i++) {
+		dst[i] = src[i] >> 2;
+	}
+}
+
 int v4lconvert_oom_error(struct v4lconvert_data *data)
 {
 	V4LCONVERT_ERR("could not allocate memory\n");
@@ -867,7 +893,8 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 #endif
 	case V4L2_PIX_FMT_SN9C2028:
 	case V4L2_PIX_FMT_SQ905C:
-	case V4L2_PIX_FMT_STV0680: { /* Not compressed but needs some shuffling */
+	case V4L2_PIX_FMT_STV0680:
+	case V4L2_PIX_FMT_SGRBG10: { /* Not compressed but needs some shuffling */
 		unsigned char *tmpbuf;
 		struct v4l2_format tmpfmt = *fmt;
 
@@ -877,6 +904,11 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 			return v4lconvert_oom_error(data);
 
 		switch (src_pix_fmt) {
+		case V4L2_PIX_FMT_SGRBG10:
+			v4lconvert_10to8(src, tmpbuf, width, height);
+
+			tmpfmt.fmt.pix.pixelformat = V4L2_PIX_FMT_SGRBG8;
+			break;
 		case V4L2_PIX_FMT_SPCA561:
 			v4lconvert_decode_spca561(src, tmpbuf, width, height);
 			tmpfmt.fmt.pix.pixelformat = V4L2_PIX_FMT_SGBRG8;
@@ -949,6 +981,7 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
 			V4LCONVERT_ERR("short raw bayer data frame\n");
 			errno = EPIPE;
 			result = -1;
+			/* FIXME: but then we proceed anyway?! */
 		}
 		switch (dest_pix_fmt) {
 		case V4L2_PIX_FMT_RGB24:




-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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