Hi Seth, On Tuesday 05 January 2010 16:54:20 Seth W wrote: > Greetings, > > I have two Microsoft LifeCam Cinema Cameras attached to a single system > (only one USB 2.0 controller). I have set trace=1024 on uvcvideo and find > that the driver allocates the same amount of bandwidth regardless of what I > specify for resolution, fps, or codec in ffmpeg, vlc, etc. > > Example: > > [r...@fedora11-test ~]# ffmpeg -f video4linux2 -s 1280x800 -r 30 -i > /dev/video1 -f m4v 2-1280-800-maxfps.m4v > FFmpeg version SVN-r20557-snapshot, Copyright (c) 2000-2009 Fabrice > Bellard, et al. > built on Nov 22 2009 01:51:55 with gcc 4.4.1 20090725 (Red Hat 4.4.1-2) > configuration: --prefix=/usr --libdir=/usr/lib --shlibdir=/usr/lib > --mandir=/usr/share/man --enable-shared --enable-gpl --enable-version3 > --enable-nonfree --enable-postproc --enable-avfilter --enable-avfilter-lavf > --enable-pthreads --enable-x11grab --enable-vdpau --disable-avisynth > --enable-libdc1394 --enable-libdirac --enable-libfaac --enable-libfaad > --enable-libfaadbin --enable-libgsm --enable-libmp3lame --enable-libnut > --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg > --enable-libschroedinger --enable-libspeex --enable-libtheora > --enable-libvorbis --enable-libx264 --enable-libxvid --extra-cflags='-O2 -g > -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector > --param=ssp-buffer-size=4 -m32 -march=i586 -mtune=generic > -fasynchronous-unwind-tables' --disable-stripping > libavutil 50. 4. 0 / 50. 4. 0 > libavcodec 52.41. 0 / 52.41. 0 > libavformat 52.39. 2 / 52.39. 2 > libavdevice 52. 2. 0 / 52. 2. 0 > libavfilter 1. 8. 0 / 1. 8. 0 > libswscale 0. 7. 1 / 0. 7. 1 > libpostproc 51. 2. 0 / 51. 2. 0 > [video4linux2 @ 0x858a860][3]Capabilities: 4000001 > Input #0, video4linux2, from '/dev/video1': > Duration: N/A, start: 1262673238.027945, bitrate: 491519 kb/s > Stream #0.0: Video: rawvideo, yuyv422, 1280x800, 491519 kb/s, 30 tbr, > 1000k tbn, 30 tbc > Output #0, m4v, to '2-1280-800-maxfps.m4v': > Stream #0.0: Video: mpeg4, yuv420p, 1280x800, q=2-31, 200 kb/s, 90k > tbn, 30 tbc > Stream mapping: > Stream #0.0 -> #0.0 > Press [q] to stop encoding > frame= 147 fps= 30 q=31.0 Lsize= 356kB time=4.90 bitrate= 595.6kbits/s > video:356kB audio:0kB global headers:0kB muxing overhead 0.000000% > > And from dmesg: > > uvcvideo: Device requested 3072 B/frame bandwidth. > uvcvideo: Allocated 5 URB buffers of 32x3072 bytes each. > > --- > > [r...@fedora11-test ~]# ffmpeg -f video4linux2 -s 640x480 -r 30 -i > /dev/video1 -f m4v 2-640x480.m4v > FFmpeg version SVN-r20557-snapshot, Copyright (c) 2000-2009 Fabrice > Bellard, et al. > built on Nov 22 2009 01:51:55 with gcc 4.4.1 20090725 (Red Hat 4.4.1-2) > configuration: --prefix=/usr --libdir=/usr/lib --shlibdir=/usr/lib > --mandir=/usr/share/man --enable-shared --enable-gpl --enable-version3 > --enable-nonfree --enable-postproc --enable-avfilter --enable-avfilter-lavf > --enable-pthreads --enable-x11grab --enable-vdpau --disable-avisynth > --enable-libdc1394 --enable-libdirac --enable-libfaac --enable-libfaad > --enable-libfaadbin --enable-libgsm --enable-libmp3lame --enable-libnut > --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg > --enable-libschroedinger --enable-libspeex --enable-libtheora > --enable-libvorbis --enable-libx264 --enable-libxvid --extra-cflags='-O2 -g > -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector > --param=ssp-buffer-size=4 -m32 -march=i586 -mtune=generic > -fasynchronous-unwind-tables' --disable-stripping > libavutil 50. 4. 0 / 50. 4. 0 > libavcodec 52.41. 0 / 52.41. 0 > libavformat 52.39. 2 / 52.39. 2 > libavdevice 52. 2. 0 / 52. 2. 0 > libavfilter 1. 8. 0 / 1. 8. 0 > libswscale 0. 7. 1 / 0. 7. 1 > libpostproc 51. 2. 0 / 51. 2. 0 > [video4linux2 @ 0x9a15860][3]Capabilities: 4000001 > Input #0, video4linux2, from '/dev/video1': > Duration: N/A, start: 1262673302.162194, bitrate: 147456 kb/s > Stream #0.0: Video: rawvideo, yuyv422, 640x480, 147456 kb/s, 30 tbr, > 1000k tbn, 30 tbc > Output #0, m4v, to '2-640x480.m4v': > Stream #0.0: Video: mpeg4, yuv420p, 640x480, q=2-31, 200 kb/s, 90k tbn, > 30 tbc > Stream mapping: > Stream #0.0 -> #0.0 > Press [q] to stop encoding > frame= 152 fps= 30 q=5.2 Lsize= 347kB time=5.07 bitrate= 561.4kbits/s > video:347kB audio:0kB global headers:0kB muxing overhead 0.000000% > > > and from dmesg: > > vcvideo: Device requested 3072 B/frame bandwidth. > uvcvideo: Allocated 5 URB buffers of 32x3072 bytes each. > > > ---- > > I had planned on showing the example from dmesg of the same allocation when > using mencoder with --v4l2-chroma=mjpeg ; but unfortunately the machine is > remote and just died... > > At any rate, if anyone can verify that this is the (in)correct behavior of > uvcvideo i would appreciate it (but I am under the impression it is not > supposed to work this way, and is supposed to allocate bandwidth based on > the input parameters). I would be happy to provide any debugging > information necessary.
Could you please send me the lsusb -v output for your cameras ? -- Regards, Laurent Pinchart _______________________________________________ Linux-uvc-devel mailing list Linux-uvc-devel@lists.berlios.de https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
