and resolution does not help at all. See paste at end of post.
On 11/13/06,
Martin Rubli <[EMAIL PROTECTED]> wrote:
On Mon, 13 Nov 2006 19:46:25 +0100, Vidar Normann <[EMAIL PROTECTED]>
wrote:
> after a discussion on ffmpeg's mailing-list it seems the reason I'm
> unable to record
> from two webcams at the same time lies in the uvc-driver..
> I am able to record from either of the webcams, but if I try to record at
> the same time
> I get the following error when invoking the ffmpeg-command to record from
> /dev/video1
> while another ffmpeg is recording from /dev/video0:
> --
> ioctl(VIDIOC_STREAMON): No space left on device
> Could not find video grab device
> --
> I notice that the last entry in dmesg is this:
> --
> uvcvideo: Failed to submit isoc URB 0 (-28).
> --
>
> Is there a bug in uvc or is there another explanation?
> FYI I'm using the Logitech QuickCam for Notebooks for Pro and
> using the newest CVS of the Split-branch of UVC.
What resolutions and frame rates are you using? Have you tried QVGA? I
know I had two cameras work at the same time but I may never have tried
resolutions above QVGA.
Cheers,
Martin
I reran both commands:
ffmpeg -vd "/dev/video1" -an -vcodec mpeg4 -s 320x240 -r 5 -y "test2.avi"
FFmpeg version SVN-r7012, Copyright (c) 2000-2006 Fabrice Bellard, et al.
configuration: --enable-xvid --enable-gpl
libavutil version: 49.0.2
libavcodec version: 51.25.0
libavformat version: 51.6.0
built on Nov 13 2006 15:34:26, gcc: 3.3.5 (Debian 1:3.3.5-13)
[video4linux2 @ 0x83a81f0][4]Capabilities: 4000001
The V4L2 driver changed the video from 320x240 to 1024x576
Input #0, video4linux2, from '':
Duration: N/A, bitrate: N/A
Stream #0.0: Video: rawvideo, yuv422, 1024x576, 47185 kb/s, 5.00 fps(r)
PIX_FMT_YUV420P will be used as an intermediate format for rescaling
Output #0, avi, to 'test2.avi':
Stream #0.0: Video: mpeg4, yuv420p, 320x240, q=2-31, 200 kb/s, 5.00 fps(c)
Stream mapping:
Stream #0.0 -> #0.0
Press [q] to stop encoding
frame= 80 q=2.0 Lsize= 221kB time= 16.0 bitrate= 113.0kbits/s
video:213kB audio:0kB global headers:0kB muxing overhead 3.500250%
--
So far so good, it records until I press 'q', the problem arises when I try to record from the other
webcam as well:
--
ffmpeg -vd "/dev/video0" -an -vcodec mpeg4 -s 320x240 -r 5 -y "test1.avi"
FFmpeg version SVN-r7012, Copyright (c) 2000-2006 Fabrice Bellard, et al.
configuration: --enable-xvid --enable-gpl
libavutil version: 49.0.2
libavcodec version: 51.25.0
libavformat version: 51.6.0
built on Nov 13 2006 15:34:26, gcc: 3.3.5 (Debian 1:3.3.5-13)
[video4linux2 @ 0x83a81f0][4]Capabilities: 4000001
The V4L2 driver changed the video from 320x240 to 1024x576
ioctl(VIDIOC_STREAMON): No space left on device
Could not find video grab device
--
The thing that I notice is the third last line, seems the v4l2-driver forces transfer in a 1024x576
resolution? Other than that, I have no idea and I don't know what to do.
Regards,
Vidar
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