[FFmpeg-trac] #383(undetermined:new): ffmpeg SCR moves backwards in output muxed mpeg file

[FFmpeg]

#383: ffmpeg SCR moves backwards in output muxed mpeg file
---------------------------------------+--------------------------
 Reporter:  johnnyquid                 |        Type:  defect
   Status:  new                        |    Priority:  normal
Component:  undetermined               |     Version:  unspecified
 Keywords:  ffmpeg mpeg scr backwards  |  Blocked By:
 Blocking:                             |  Reproduced:  0
 Analyzed:  0                          |
---------------------------------------+--------------------------
 I am not sure where to properly post bug reports so bear with me that I
 also posted in the ffmpeg-users as well.  The issue was reported in Oct
 2010 and fixed but the fix does not always seem to work.  See http
 ://ffmpeg-users.933282.n4.nabble.com/FFMPEG-encoded-MPEG-2-video-causes-
 error-in-DVDAuthor-td2995983.html for details.  The issue is summarized
 below:

 The following command is used to encode videos in MPEG-2 (vob) format
 for DVD authoring:

 ffmpeg -i invideo.avi -target pal-dvd -f dvd outvideo.vob

 ('-target' can also be 'ntsc-dvd' or 'film-dvd')

 Video streams encoded in this manner using the latest SVN will cause the
 following error in DVDAuthor:

 'ERR:  SCR moves backwards, remultiplex input.'

 DVD authoring then stops. Demuxing the streams and using them
 individually, or remuxing them again, will make the error message
 disappear, but the resulting MPEG-2 files (m2v or vob) or DVD are
 problematic (choppy playback, no or wrong total playing time).

 This issue appeared with SVN-r25383, when the following two lines were
 added in libavformat/mpegenc.c:

 1163   if(!s->last_scr)
 1164   s->last_scr= dts;

 The current source code has changed to:

  The new code in mpegenc.c starting at line 1163 is now (but the issue
 still exists):

     pts= pkt->pts;
     dts= pkt->dts;

     if(pts != AV_NOPTS_VALUE) pts += 2*preload;
     if(dts != AV_NOPTS_VALUE){
         if(!s->last_scr)
             s->last_scr= dts + preload;
         dts += 2*preload;
     }


 The error is shown in the below output from ffmpeg and dvdauthor:

 See the ffmpeg and dvdauthor output below:

 E:\Temp\bugfiles>ffmpeg -v 9 -loglevel 99 -i ranft.m2v -itsoffset
 -00:00:00.775
 -i ranft.ac3 -vcodec copy -acodec copy -target ntsc-dvd -y ranft.mpg
 ffmpeg version N-31653-gfaa3381, Copyright (c) 2000-2011 the FFmpeg
 developers
   built on Jul 28 2011 01:57:12 with gcc 4.6.1
   configuration: --enable-gpl --enable-version3 --enable-memalign-hack
 --enable-
 runtime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r
 --enable-libo
 pencore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-
 libgsm --
 enable-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-
 libschroedinger
  --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libvpx
 --enabl
 e-libx264 --enable-libxavs --enable-libxvid --enable-zlib
   libavutil    51. 11. 0 / 51. 11. 0
   libavcodec   53.  9. 0 / 53.  9. 0
   libavformat  53.  6. 0 / 53.  6. 0
   libavdevice  53.  2. 0 / 53.  2. 0
   libavfilter   2. 27. 3 /  2. 27. 3
   libswscale    2.  0. 0 /  2.  0. 0
   libpostproc  51.  2. 0 / 51.  2. 0
 [mpegvideo @ 01F2B5C0] Format mpegvideo probed with size=32768 and
 score=51
 [mpeg1video @ 02000260] Unsupported bit depth: 0
 [mpegvideo @ 01F2B5C0] max_analyze_duration 5000000 reached at 5005000
 [mpegvideo @ 01F2B5C0] Estimating duration from bitrate, this may be
 inaccurate
 Input #0, mpegvideo, from 'ranft.m2v':
   Duration: 00:00:08.88, bitrate: 8999 kb/s
     Stream #0.0, 152, 1/1200000: Video: mpeg2video (Main), yuv420p,
 720x480 [PAR
  32:27 DAR 16:9], 1001/60000, 9000 kb/s, 29.97 fps, 29.97 tbr, 1200k tbn,
 59.94
 tbc
 [ac3 @ 01F2F720] Format ac3 probed with size=8192 and score=51
 [ac3 @ 01F297A0] Unsupported bit depth: 0
 [ac3 @ 01F2F720] max_analyze_duration 5000000 reached at 5024000
 [ac3 @ 01F2F720] Estimating duration from bitrate, this may be inaccurate
 Input #1, ac3, from 'ranft.ac3':
   Duration: 00:00:20.83, start: 0.000000, bitrate: 384 kb/s
     Stream #1.0, 159, 1/90000: Audio: ac3, 48000 Hz, 5.1, s16, 384 kb/s
 Output #0, dvd, to 'ranft.mpg':
   Metadata:
     encoder         : Lavf53.6.0
     Stream #0.0, 0, 1/90000: Video: mpeg2video, yuv420p, 720x480 [PAR
 32:27 DAR
 16:9], 1001/30000, q=2-31, 9000 kb/s, 90k tbn, 29.97 tbc
     Stream #0.1, 0, 1/90000: Audio: ac3, 48000 Hz, 5.1, 384 kb/s
 Stream mapping:
   Stream #0.0 -> #0.0
   Stream #1.0 -> #0.1
 Press [q] to stop, [?] for help
 frame=  573 fps=  0 q=-1.0 Lsize=   10882kB time=00:00:19.11
 bitrate=4662.6kbits
 /s
 video:9766kB audio:977kB global headers:0kB muxing overhead 1.301527%

 E:\Temp\bugfiles>E:\Temp\bugfiles>dvdauthor.exe -o dvdtest -x dvd.xml
 DVDAuthor::dvdauthor, version 0.6.18.
 Build options: gnugetopt iconv freetype fribidi
 Send bugs to <dvdauthor-users at lists.sourceforge.net>

 INFO: dvdauthor creating VTS
 STAT: Picking VTS 01

 STAT: Processing e:\temp\bugfiles\ranft.mpg...
 ERR: SCR moves backwards, remultiplex input: 23131 < 8589910134

 E:\Temp\bugfiles>

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/383>
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