Francois Visagie <[email protected]> added the comment:

This has been reproduced on FFmpeg version SVN-r18923:

SITUATION AND PROBLEM DESCRIPTION
---------------------------------

I am using FFmpeg version SVN-r18923 on Windows XP 
SP3. When transcoding from DV AVI to DVD-compliant 
MPEG-2 many "AC EOB marker is absent" messages appear 
and it seems the corresponding input is discarded 
(does not appear in the output file).

COMMAND LINE
------------

ffmpeg -i FFmpeg_AC_EOB_marker_is_absent.avi -target 
pal-dvd -ab 128000 -flags ildct+ilme -vcodec 
mpeg2video -b 6150000 
FFmpeg_AC_EOB_marker_is_absent.mpg
 
SAMPLE DATA
-----------

A sample video file which produces the below console 
output has been uploaded to 
ftp://upload.ffmpeg.org/MPlayer/incoming/FFmpeg_AC_EOB_
marker_is_absent.

CONSOLE OUTPUT
--------------

FFmpeg version SVN-r18923, Copyright (c) 2000-2009 
Fabrice Bellard, et al.
  configuration: --enable-memalign-hack --
prefix=/mingw --cross-prefix=i686-mingw32- --cc=ccache-
i686-mingw32-gcc --targ
et-os=mingw32 --arch=i686 --cpu=i686 --enable-
avisynth --enable-gpl --enable-zlib --enable-bzlib --
enable-libgsm --enabl
e-libfaad --enable-pthreads --enable-libvorbis --
enable-libtheora --enable-libspeex --enable-
libmp3lame --enable-libopen
jpeg --enable-libxvid --enable-libschroedinger --
enable-libx264
  libavutil     50. 3. 0 / 50. 3. 0
  libavcodec    52.29. 0 / 52.29. 0
  libavformat   52.33. 0 / 52.33. 0
  libavdevice   52. 2. 0 / 52. 2. 0
  libswscale     0. 7. 1 /  0. 7. 1
  built on May 24 2009 04:02:38, gcc: 4.2.4
Input #0, avi, 
from 'FFmpeg_AC_EOB_marker_is_absent.avi':
  Duration: 00:00:02.00, start: 0.000000, bitrate: 
30336 kb/s
    Stream #0.0: Video: dvvideo, yuv420p, 720x576, 
28800 kb/s, PAR 59:54 DAR 295:216, 25 tbr, 25 tbn, 25 
tbc
    Stream #0.1: Audio: pcm_s16le, 48000 Hz, stereo, 
s16, 1536 kb/s
[NULL @ 0x3e4e90]Unknown option 'gop'
[swscaler @ 0x3e5e20]Unknown option 'gop'
[ac3 @ 0x19314a0]No channel layout specified. The 
encoder will guess the layout, but it might be 
incorrect.
Output #0, dvd, 
to 'FFmpeg_AC_EOB_marker_is_absent.mpg':
    Stream #0.0: Video: mpeg2video, yuv420p, 720x576 
[PAR 59:54 DAR 295:216], q=2-31, 6150 kb/s, 90k tbn, 
25 tbc
    Stream #0.1: Audio: ac3, 48000 Hz, stereo, s16, 
128 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
  Stream #0.1 -> #0.1
Press [q] to stop encoding
AC EOB marker is absent pos=66=       6kB time=0.19 
bitrate= 256.0kbits/s
AC EOB marker is absent pos=64
    Last message repeated 1 times
AC EOB marker is absent pos=69
AC EOB marker is absent pos=64
    Last message repeated 7 times
AC EOB marker is absent pos=68
AC EOB marker is absent pos=64
    Last message repeated 3 times
AC EOB marker is absent pos=67
AC EOB marker is absent pos=70
AC EOB marker is absent pos=64
    Last message repeated 7 times
AC EOB marker is absent pos=76
AC EOB marker is absent pos=64
    Last message repeated 1 times
AC EOB marker is absent pos=66
AC EOB marker is absent pos=64
AC EOB marker is absent pos=68
AC EOB marker is absent pos=64
    Last message repeated 17 times
AC EOB marker is absent pos=75
AC EOB marker is absent pos=65
    Last message repeated 1 times
AC EOB marker is absent pos=64
    Last message repeated 1 times
AC EOB marker is absent pos=67
AC EOB marker is absent pos=64
    Last message repeated 7 times
AC EOB marker is absent pos=65
AC EOB marker is absent pos=64
    Last message repeated 3 times
AC EOB marker is absent pos=66
AC EOB marker is absent pos=67
AC EOB marker is absent pos=64
    Last message repeated 6 times
AC EOB marker is absent pos=69
AC EOB marker is absent pos=64
    Last message repeated 3 times
AC EOB marker is absent pos=66
AC EOB marker is absent pos=64
    Last message repeated 11 times
AC EOB marker is absent pos=65
AC EOB marker is absent pos=64
AC EOB marker is absent pos=65
AC EOB marker is absent pos=64
    Last message repeated 3 times
AC EOB marker is absent pos=71
AC EOB marker is absent pos=64
    Last message repeated 1 times
AC EOB marker is absent pos=74
AC EOB marker is absent pos=64
AC EOB marker is absent pos=66
AC EOB marker is absent pos=64
    Last message repeated 2 times
AC EOB marker is absent pos=66
    Last message repeated 1 times
AC EOB marker is absent pos=73
AC EOB marker is absent pos=64
AC EOB marker is absent pos=74
AC EOB marker is absent pos=64
    Last message repeated 2 times
AC EOB marker is absent pos=67
AC EOB marker is absent pos=68
AC EOB marker is absent pos=64
AC EOB marker is absent pos=69
AC EOB marker is absent pos=67
AC EOB marker is absent pos=69
AC EOB marker is absent pos=64
    Last message repeated 1 times
AC EOB marker is absent pos=66
    Last message repeated 1 times
AC EOB marker is absent pos=65
AC EOB marker is absent pos=64
    Last message repeated 5 times
AC EOB marker is absent pos=65
AC EOB marker is absent pos=64
AC EOB marker is absent pos=72
AC EOB marker is absent pos=64
    Last message repeated 1 times
AC EOB marker is absent pos=67
AC EOB marker is absent pos=64
    Last message repeated 2 times
AC EOB marker is absent pos=65
AC EOB marker is absent pos=64
frame=    8 fps=  0 q=5.0 Lsize=     392kB time=0.28 
bitrate=11468.8kbits/s
video:378kB audio:5kB global headers:0kB muxing 
overhead 2.281802%

Perhaps this is not due to a bug, but possibly to 
unnecessarily strict input validation? For example, 
could it be relaxed by saying: if no AC EOB marker is 
encountered where expected, let's deduce where it 
should have been and move on?

Also, MEncoder successfully decodes and processes this 
file. Because the sample file is a little messy, 
MEncoder does need a little help with recognising the 
file format (-demuxer lavf), but its qdv decoder 
handles the content flawlessly.

Therefore, it might not be a bad idea to inspect the 
MEncoder qdv code for tips. An even better idea might 
be to simply borrow the qdv decoder instead of working 
on the current DV decoder?

----------
nosy: +fvisagie

_____________________________________________________
FFmpeg issue tracker <[email protected]>
<https://roundup.ffmpeg.org/roundup/ffmpeg/issue1060>
_____________________________________________________

Reply via email to