Hi,

> > 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,
> > 5.00fps(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.
>
> That looks weird, indeed. The UVC driver doesn't do that, however.

Except when asked for it :-) You're probably asking the webcam to stream in 
YUV format, and first generation hardware doesn't support low resolutions in 
YUV. You will have to set the format to MJPEG, or get a newer webcam if you 
absolutely need YUV at low resolutions.

Cheers,

Laurent Pinchart
_______________________________________________
Linux-uvc-devel mailing list
[email protected]
https://lists.berlios.de/mailman/listinfo/linux-uvc-devel

Reply via email to