From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mailout1.w1.samsung.com ([210.118.77.11]:37421 "EHLO mailout1.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759986Ab2D0OXg (ORCPT ); Fri, 27 Apr 2012 10:23:36 -0400 Received: from euspt2 (mailout1.w1.samsung.com [210.118.77.11]) by mailout1.w1.samsung.com (iPlanet Messaging Server 5.2 Patch 2 (built Jul 14 2004)) with ESMTP id <0M35000N46KR7O@mailout1.w1.samsung.com> for linux-media@vger.kernel.org; Fri, 27 Apr 2012 15:22:03 +0100 (BST) Received: from linux.samsung.com ([106.116.38.10]) by spt2.w1.samsung.com (iPlanet Messaging Server 5.2 Patch 2 (built Jul 14 2004)) with ESMTPA id <0M3500LLY6N7JR@spt2.w1.samsung.com> for linux-media@vger.kernel.org; Fri, 27 Apr 2012 15:23:31 +0100 (BST) Date: Fri, 27 Apr 2012 16:23:19 +0200 From: Sylwester Nawrocki Subject: [PATCH/RFC v3 02/14] V4L: Add camera exposure bias control In-reply-to: <1335536611-4298-1-git-send-email-s.nawrocki@samsung.com> To: linux-media@vger.kernel.org Cc: laurent.pinchart@ideasonboard.com, sakari.ailus@iki.fi, g.liakhovetski@gmx.de, hdegoede@redhat.com, moinejf@free.fr, hverkuil@xs4all.nl, m.szyprowski@samsung.com, riverful.kim@samsung.com, sw0312.kim@samsung.com, s.nawrocki@samsung.com, Kyungmin Park Message-id: <1335536611-4298-3-git-send-email-s.nawrocki@samsung.com> MIME-version: 1.0 Content-type: TEXT/PLAIN Content-transfer-encoding: 7BIT References: <1335536611-4298-1-git-send-email-s.nawrocki@samsung.com> Sender: linux-media-owner@vger.kernel.org List-ID: The camera may in some conditions incorrectly determine the exposure, and a manual automatic exposure correction may be needed. This patch adds V4L2_CID_AUTO_EXPOSURE_BIAS control which allows to add some offset in the automatic exposure control loop, to compensate for frame under- or over-exposure. Signed-off-by: Sylwester Nawrocki Signed-off-by: Kyungmin Park --- Documentation/DocBook/media/v4l/controls.xml | 16 ++++++++++++++++ drivers/media/video/v4l2-ctrls.c | 4 ++++ include/linux/videodev2.h | 2 ++ 3 files changed, 22 insertions(+) diff --git a/Documentation/DocBook/media/v4l/controls.xml b/Documentation/DocBook/media/v4l/controls.xml index 5038a3a..56a53a8 100644 --- a/Documentation/DocBook/media/v4l/controls.xml +++ b/Documentation/DocBook/media/v4l/controls.xml @@ -2775,6 +2775,22 @@ remain constant. + V4L2_CID_EXPOSURE_BIAS + integer menu + Determines the automatic +exposure compensation, it is effective only when V4L2_CID_EXPOSURE_AUTO +control is set to AUTO, SHUTTER_PRIORITY +or APERTURE_PRIORITY. +It is expressed in terms of EV, drivers should interpret the values as 0.001 EV +units, where the value 1000 stands for +1 EV. +Increasing the exposure compensation value is equivalent to decreasing +the exposure value (EV) and will increase the amount of light at the image +sensor. The camera performs the exposure compensation by adjusting absolute +exposure time and/or aperture. + + + + V4L2_CID_PAN_RELATIVE integer This control turns the diff --git a/drivers/media/video/v4l2-ctrls.c b/drivers/media/video/v4l2-ctrls.c index e0725b5..1d7091f 100644 --- a/drivers/media/video/v4l2-ctrls.c +++ b/drivers/media/video/v4l2-ctrls.c @@ -597,6 +597,7 @@ const char *v4l2_ctrl_get_name(u32 id) case V4L2_CID_PRIVACY: return "Privacy"; case V4L2_CID_IRIS_ABSOLUTE: return "Iris, Absolute"; case V4L2_CID_IRIS_RELATIVE: return "Iris, Relative"; + case V4L2_CID_AUTO_EXPOSURE_BIAS: return "Auto Exposure, Bias"; /* FM Radio Modulator control */ /* Keep the order of the 'case's the same as in videodev2.h! */ @@ -739,6 +740,9 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, case V4L2_CID_RDS_TX_RADIO_TEXT: *type = V4L2_CTRL_TYPE_STRING; break; + case V4L2_CID_AUTO_EXPOSURE_BIAS: + *type = V4L2_CTRL_TYPE_INTEGER_MENU; + break; case V4L2_CID_USER_CLASS: case V4L2_CID_CAMERA_CLASS: case V4L2_CID_MPEG_CLASS: diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h index 5a09ac3..da60cbb 100644 --- a/include/linux/videodev2.h +++ b/include/linux/videodev2.h @@ -1693,6 +1693,8 @@ enum v4l2_exposure_auto_type { #define V4L2_CID_IRIS_ABSOLUTE (V4L2_CID_CAMERA_CLASS_BASE+17) #define V4L2_CID_IRIS_RELATIVE (V4L2_CID_CAMERA_CLASS_BASE+18) +#define V4L2_CID_AUTO_EXPOSURE_BIAS (V4L2_CID_CAMERA_CLASS_BASE+19) + /* FM Modulator class control IDs */ #define V4L2_CID_FM_TX_CLASS_BASE (V4L2_CTRL_CLASS_FM_TX | 0x900) #define V4L2_CID_FM_TX_CLASS (V4L2_CTRL_CLASS_FM_TX | 1) -- 1.7.10