[FFmpeg-devel] Invalid and inefficient vfw-avi packed B frames detected

[Sheyong Shim]

I got message(Invalid and inefficient vfw-avi packed B frames
detected) while video was converted.

After converting the video, I checked pixel values in video.

Values are different from original video.

Why values change after converting?

Please tell me why.

Please send me an answer*.*

ffmpeg version 1.1.1 Copyright (c) 2000-2013 the FFmpeg developers
  built on Jan 20 2013 23:05:28 with gcc 4.7.2 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads
--enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r
--enable-gnutls --enable-libass --enable-libbluray --enable-libcaca
--enable-libfreetype --enable-libgsm --enable-libmp3lame
--enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg
--enable-libopus --enable-librtmp --enable-libschroedinger
--enable-libspeex --enable-libtheora --enable-libtwolame
--enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis
--enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid
--enable-zlib
  libavutil      52. 13.100 / 52. 13.100
  libavcodec     54. 86.100 / 54. 86.100
  libavformat    54. 59.106 / 54. 59.106
  libavdevice    54.  3.102 / 54.  3.102
  libavfilter     3. 32.100 /  3. 32.100
  libswscale      2.  1.103 /  2.  1.103
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100
[mpeg4 @ 02e218c0] Invalid and inefficient vfw-avi packed B frames detected
Input #0, avi, from 'D:\video_output\avi\1.avi':
  Metadata:
    encoder         : Lavf54.59.106
  Duration: 00:04:25.52, start: 0.000000, bitrate: 2744 kb/s
    Stream #0:0: Video: mpeg4 (Advanced Simple Profile) (DX50 /
0x30355844), yuv420p, 720x544 [SAR 1:1 DAR 45:34], 25 tbr, 25 tbn, 25 tbc
    Stream #0:1: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, stereo, fltp,
192 kb/s
Output #0, matroska, to 'D:\video_output\avi\1_2.mkv':
  Metadata:
    encoder         : Lavf54.59.106
    Stream #0:0: Video: ffv1 (FFV1 / 0x31564646), yuv420p, 720x544 [SAR 1:1
DAR 45:34], q=2-31, 200 kb/s, 1k tbn, 25 tbc
    Stream #0:1: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (mpeg4 -> ffv1)
  Stream #0:1 -> #0:1 (ac3 -> pcm_s16le)
Press [q] to stop, [?] for help
[mpeg4 @ 02e27920] Invalid and inefficient vfw-avi packed B frames detected
frame=   36 fps=0.0 q=0.0 size=    1916kB time=00:00:01.56
bitrate=10008.5kbits/s


...


frame= 6565 fps= 46 q=0.0 size=  862611kB time=00:04:22.72
bitrate=26897.5kbits/s
frame= 6594 fps= 46 q=0.0 size=  864799kB time=00:04:23.87
bitrate=26848.0kbits/s
frame CRC mismatch
frame= 6629 fps= 46 q=0.0 size=  866407kB time=00:04:25.20
bitrate=26763.2kbits/s
frame= 6638 fps= 46 q=0.0 Lsize=  866521kB time=00:04:25.56
bitrate=26730.5kbits/s

video:816725kB audio:49668kB subtitle:0 global headers:0kB muxing overhead
0.014713%