[FFmpeg-user] Capture from USB Dazzle: *** dropping frames

[MrNice]

On 30/07/15 12:28, Carl Eugen Hoyos wrote:
> MrNice <wxcvbn2006 <at> iol.ie> writes:
> 
>> At this time, the output image is not good at all; 
>> It looks like a lot of lines are missing, white 
>> areas are ribbed by black lines.
> 
> Is this also reproducible if you record without 
> audio, something like:
> $ ffmpeg -channel 1 -i /dev/video0 -qscale 2 out.avi
> ?
> 
> Carl Eugen
> 

Yes, same issue

./ffmpeg -channel 1 -i /dev/video0 -qscale 2 out.avi
ffmpeg version N-73832-g736a386 Copyright (c) 2000-2015 the FFmpeg
developers
  built with gcc 5.1.1 (GCC) 20150618 (Red Hat 5.1.1-4)
  configuration: --enable-libpulse --enable-gpl --enable-libx264
  libavutil      54. 28.100 / 54. 28.100
  libavcodec     56. 49.101 / 56. 49.101
  libavformat    56. 40.101 / 56. 40.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 25.100 /  5. 25.100
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.101 /  1.  2.101
  libpostproc    53.  3.100 / 53.  3.100
Input #0, video4linux2,v4l2, from '/dev/video0':
  Duration: N/A, start: 5087.713285, bitrate: 165888 kb/s
    Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 720x576,
165888 kb/s, 25 fps, 25 tbr, 1000k tbn, 1000k tbc
Please use -q:a or -q:v, -qscale is ambiguous
Output #0, avi, to 'out.avi':
  Metadata:
    ISFT            : Lavf56.40.101
    Stream #0:0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 720x576,
q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc
    Metadata:
      encoder         : Lavc56.49.101 mpeg4
Stream mapping:
  Stream #0:0 -> #0:0 (rawvideo (native) -> mpeg4 (native))
Press [q] to stop, [?] for help
Past duration 0.798866 too large
Past duration 0.802269 too large
Past duration 0.801369 too large
Past duration 0.601936 too large     75kB time=00:00:00.56
bitrate=1098.4kbits/s dup=0 drop=1
Past duration 0.801949 too large
Past duration 0.602592 too large
Past duration 0.802589 too large
Past duration 0.603249 too large
Past duration 0.803017 too large
Past duration 0.605598 too large    112kB time=00:00:01.12 bitrate=
822.2kbits/s dup=0 drop=4
Past duration 0.803474 too large
Past duration 0.604515 too large
Past duration 0.804222 too large
Past duration 0.804695 too large    150kB time=00:00:01.60 bitrate=
769.7kbits/s dup=0 drop=6
Past duration 0.805443 too large
Past duration 0.806023 too large
Past duration 0.806664 too large    187kB time=00:00:02.12 bitrate=
721.1kbits/s dup=0 drop=9
Past duration 0.807198 too large
Past duration 0.807747 too large    224kB time=00:00:02.60 bitrate=
707.2kbits/s dup=0 drop=11
Past duration 0.808342 too large
Past duration 0.808922 too large
Past duration 0.809517 too large    261kB time=00:00:03.12 bitrate=
685.0kbits/s dup=0 drop=14
Past duration 0.810066 too large
Past duration 0.810692 too large    299kB time=00:00:03.60 bitrate=
680.8kbits/s dup=0 drop=16
frame=   92 fps= 26 q=2.0 Lsize=     302kB time=00:00:03.68 bitrate=
671.6kbits/s dup=0 drop=17
video:294kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: 2.637751%