[FFmpeg-trac] #4030(avdevice:new): V4L2 recording results in invalid data & buffer still owned errors

[FFmpeg]

#4030: V4L2 recording results in invalid data & buffer still owned errors
-------------------------------------+------------------------------------
             Reporter:  thender      |                    Owner:
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:  avdevice
              Version:  unspecified  |               Resolution:
             Keywords:  v4l2         |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
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Comment (by thender):

 I tried recompiling with just configure, and I also tried your patch.
 Since compiling with nothing but ./configure does not give you x264 as a
 codec, I just decided to specify no video codec which defaulted to mpeg4.
 It still doesn't work.

  $ ffmpeg -f v4l2 -framerate 30 -s 1920x1080 -i /dev/video0
 microtester.mkv
 ffmpeg version N-66880-ga92192d Copyright (c) 2000-2014 the FFmpeg
 developers
   built on Oct 16 2014 14:08:29 with gcc 4.8.3 (Gentoo 4.8.3 p1.1,
 pie-0.5.9)
   configuration: --prefix=/usr
   libavutil      54. 10.100 / 54. 10.100
   libavcodec     56.  7.100 / 56.  7.100
   libavformat    56.  9.100 / 56.  9.100
   libavdevice    56.  1.100 / 56.  1.100
   libavfilter     5.  1.106 /  5.  1.106
   libswscale      3.  1.101 /  3.  1.101
   libswresample   1.  1.100 /  1.  1.100
 [video4linux2,v4l2 @ 0x1e46dc0] The v4l2 frame is 0 bytes, but 4147200
 bytes are expected. Flags: 0x00002045
 Input #0, video4linux2,v4l2, from '/dev/video0':
   Duration: N/A, bitrate: 995328 kb/s
     Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 1920x1080,
 995328 kb/s, 30 fps, 30 tbr, 1000k tbn, 1000k tbc
 Output #0, matroska, to 'microtester.mkv':
   Metadata:
     encoder         : Lavf56.9.100
     Stream #0:0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 1920x1080,
 q=2-31, 200 kb/s, 30 fps, 1k tbn, 30 tbc
     Metadata:
       encoder         : Lavc56.7.100 mpeg4
 Stream mapping:
   Stream #0:0 -> #0:0 (rawvideo (native) -> mpeg4 (native))
 Press [q] to stop, [?] for help
 [video4linux2,v4l2 @ 0x1e46dc0] The v4l2 frame is 0 bytes, but 4147200
 bytes are expected. Flags: 0x00002045
 /dev/video0: Invalid data found when processing input
 frame=    0 fps=0.0 q=0.0 Lsize=       1kB time=00:00:00.00 bitrate=N/A
 video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: unknown


 If anyone else has this problem, VLC version 3 works with framerate. The
 reason I was using ffmpeg is because VLC was not letting me set the
 framerate of an input source with the stable version, but version 3 of VLC
 adds this functionality. If this buffer stuff gets fixed in ffmpeg, I'd
 love to go back to ffmpeg, but just incase someone else is in the same
 situation I am with a magewell USB3 HDMI capture device and needs
 something that works now, you can use a command line like this with VLC to
 record video & audio just fine. It never freezes and always works.

 cvlc v4l2:// :v4l2-dev=/dev/video0 :v4l2-fps=30 :v4l2-width=1920
 :v4l2-height=1080 --input-slave pulse:// --sout
 "#transcode{vcodec=h264,venc=x264{preset=ultrafast,crf=10}}:standard{access=file,dst=camcorder.avi}"

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Ticket URL: <https://trac.ffmpeg.org/ticket/4030#comment:8>
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