Re: Bug#929262: libv4l-dev: pac207 cam(s) give frame decode errors

Re: Bug#929262: libv4l-dev: pac207 cam(s) give frame decode errors

[Gregor Jasny]

Hello,

On 20.05.19 10:25, folkert@vanheusden.com wrote:
> Trying to get a pac207 camera to work with constatus.
> 
> 2019-05-20 10:22:34.864900  INFO constatus [1-1] source v4l2 thread started
> libv4l2: error got 4 consecutive frame decode errors, last error: v4l-convert: error unknown pac207 row header: 0x0000
> 2019-05-20 10:22:35.597949 ERROR cs:src_v4l2 [1-1] VIDIOC_DQBUF failed: Input/output error
> ioctl(VIDIOC_QBUF) failed
> errno: 22 (Invalid argument)
> 
> To verify that it is not a constatus-problem I also tried a raspberry-pi camera via its video4linux-interface and that works fine.

According to the Linux Kernel Maintainers file the device driver is 
maintained by Hans, which I CC'ed on this bug report:

GSPCA PAC207 SONIXB SUBDRIVER
M:	Hans Verkuil <hverkuil@xs4all.nl>
L:	linux-media@vger.kernel.org
T:	git git://linuxtv.org/media_tree.git
S:	Odd Fixes
F:	drivers/media/usb/gspca/pac207.c

Did your camera ever work on another Kernel, CPU architecture, or 
v4l-utils version? Do you have anything suspicious in dmesg output?

Thanks,
Gregor

Re: Bug#929262: libv4l-dev: pac207 cam(s) give frame decode errors

[Hans Verkuil]

On 5/20/19 1:38 PM, Gregor Jasny wrote:
> Hello,
> 
> On 20.05.19 10:25, folkert@vanheusden.com wrote:
>> Trying to get a pac207 camera to work with constatus.
>>
>> 2019-05-20 10:22:34.864900  INFO constatus [1-1] source v4l2 thread started
>> libv4l2: error got 4 consecutive frame decode errors, last error: v4l-convert: error unknown pac207 row header: 0x0000
>> 2019-05-20 10:22:35.597949 ERROR cs:src_v4l2 [1-1] VIDIOC_DQBUF failed: Input/output error
>> ioctl(VIDIOC_QBUF) failed
>> errno: 22 (Invalid argument)
>>
>> To verify that it is not a constatus-problem I also tried a raspberry-pi camera via its video4linux-interface and that works fine.
> 
> According to the Linux Kernel Maintainers file the device driver is 
> maintained by Hans, which I CC'ed on this bug report:
> 
> GSPCA PAC207 SONIXB SUBDRIVER
> M:	Hans Verkuil <hverkuil@xs4all.nl>
> L:	linux-media@vger.kernel.org
> T:	git git://linuxtv.org/media_tree.git
> S:	Odd Fixes
> F:	drivers/media/usb/gspca/pac207.c
> 
> Did your camera ever work on another Kernel, CPU architecture, or 
> v4l-utils version? Do you have anything suspicious in dmesg output?

I strongly recommend that you buy a new webcam. This is ancient hardware.
Even the cheapest UVC webcams you can buy today will have far better
quality than a pac207. If you really, really need this to work, then I
need the full dmesg output and you also need to check if you can reproduce
this issue with the v4l2-ctl command:

v4l2-ctl -d /dev/videoX --stream-mmap

(it keeps capturing frames until you press ctrl-X)

I should have one of these webcams, but won't be able to test until next
week.

Regards,

	Hans

Re: Bug#929262: libv4l-dev: pac207 cam(s) give frame decode errors

[folkert]

Hi,

> I strongly recommend that you buy a new webcam. This is ancient hardware.
> Even the cheapest UVC webcams you can buy today will have far better
> quality than a pac207. If you really, really need this to work, then I
> need the full dmesg output and you also need to check if you can reproduce
> this issue with the v4l2-ctl command:
> 
> v4l2-ctl -d /dev/videoX --stream-mmap
> (it keeps capturing frames until you press ctrl-X)

v4l2-ctl:
- raspberry pi 2 and 3b+: fail
- laptop: ok for at least a few minutes


> I should have one of these webcams, but won't be able to test until next
> week.

Thanks but it looks to be a raspberry pi problem.