[FFmpeg-trac] #3859(undetermined:new): mp4: start_time never zero

FFmpeg trac at avcodec.org
Sat Aug 16 13:17:12 CEST 2014


#3859: mp4: start_time never zero
-------------------------------------+-------------------------------------
             Reporter:  blacktrash   |                    Owner:
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:
              Version:  git-master   |  undetermined
             Keywords:               |               Resolution:
             Blocking:               |               Blocked By:
Analyzed by developer:  0            |  Reproduced by developer:  0
-------------------------------------+-------------------------------------

Comment (by blacktrash):

 Replying to [comment:1 cehoyos]:
 > Are external libraries like libx264 and libfaac necessary to reproduce
 this?

 {{{
 $ ffmpeg -i BigBuckBunny_640x360.m4v test.ts
 ffmpeg version N-65628-g6c36b3a Copyright (c) 2000-2014 the FFmpeg
 developers
   built on Aug 14 2014 15:21:41 with Apple LLVM version 5.1
 (clang-503.0.40) (based on LLVM 3.4svn)
   configuration: --enable-gpl --enable-version3 --enable-nonfree
 --disable-ffserver --enable-shared --enable-libfdk-aac --enable-libx265
 --enable-libx264 --enable-libxvid --enable-libfaac --enable-libmp3lame
 --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libvidstab
 --extra-cflags=-I/sw/include --extra-libs=-L/sw/lib
   libavutil      54.  3.100 / 54.  3.100
   libavcodec     56.  0.100 / 56.  0.100
   libavformat    56.  1.100 / 56.  1.100
   libavdevice    56.  0.100 / 56.  0.100
   libavfilter     5.  0.100 /  5.  0.100
   libswscale      3.  0.100 /  3.  0.100
   libswresample   1.  0.100 /  1.  0.100
   libpostproc    53.  0.100 / 53.  0.100
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'BigBuckBunny_640x360.m4v':
   Metadata:
     major_brand     : M4V
     minor_version   : 1
     compatible_brands: M4V M4A mp42isom
     creation_time   : 2008-06-03 05:23:28
     copyright       : © 2008 Blender Foundation | www.bigbuckbunny.org
     title           : Big Buck Bunny
     artist          : Peach Open Movie Team
     composer        : Sacha Goedegebure / Ton Roosendaal
     date            : 2008
   Duration: 00:09:56.46, start: 0.000000, bitrate: 1626 kb/s
     Stream #0:0(eng): Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo,
 fltp, 127 kb/s (default)
     Metadata:
       creation_time   : 2008-06-03 05:23:28
       handler_name    : Apple Sound Media Handler
     Stream #0:1(eng): Video: h264 (Constrained Baseline) (avc1 /
 0x31637661), yuv420p(tv, smpte170m), 640x360, 1495 kb/s, 24 fps, 24 tbr,
 2400 tbn, 4800 tbc (default)
     Metadata:
       creation_time   : 2008-06-03 05:23:28
       handler_name    : Apple Video Media Handler
 Output #0, mpegts, to 'test.ts':
   Metadata:
     major_brand     : M4V
     minor_version   : 1
     compatible_brands: M4V M4A mp42isom
     date            : 2008
     copyright       : © 2008 Blender Foundation | www.bigbuckbunny.org
     title           : Big Buck Bunny
     artist          : Peach Open Movie Team
     composer        : Sacha Goedegebure / Ton Roosendaal
     encoder         : Lavf56.1.100
     Stream #0:0(eng): Video: mpeg2video, yuv420p, 640x360, q=2-31, 200
 kb/s, 24 fps, 90k tbn, 24 tbc (default)
     Metadata:
       creation_time   : 2008-06-03 05:23:28
       handler_name    : Apple Video Media Handler
       encoder         : Lavc56.0.100 mpeg2video
     Stream #0:1(eng): Audio: mp2, 44100 Hz, stereo, s16, 384 kb/s
 (default)
     Metadata:
       creation_time   : 2008-06-03 05:23:28
       handler_name    : Apple Sound Media Handler
       encoder         : Lavc56.0.100 mp2
 Stream mapping:
   Stream #0:1 -> #0:0 (h264 (native) -> mpeg2video (native))
   Stream #0:0 -> #0:1 (aac (native) -> mp2 (native))
 Press [q] to stop, [?] for help
 frame=14316 fps=1316 q=31.0 Lsize=   55390kB time=00:09:56.46 bitrate=
 760.7kbits/s
 video:20870kB audio:27960kB subtitle:0kB other streams:0kB global
 headers:0kB muxing overhead: 13.433609%
 $ ffprobe -show_entries format=start_time test.ts
 ffprobe version N-65628-g6c36b3a Copyright (c) 2007-2014 the FFmpeg
 developers
   built on Aug 14 2014 15:21:41 with Apple LLVM version 5.1
 (clang-503.0.40) (based on LLVM 3.4svn)
   configuration: --enable-gpl --enable-version3 --enable-nonfree
 --disable-ffserver --enable-shared --enable-libfdk-aac --enable-libx265
 --enable-libx264 --enable-libxvid --enable-libfaac --enable-libmp3lame
 --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libvidstab
 --extra-cflags=-I/sw/include --extra-libs=-L/sw/lib
   libavutil      54.  3.100 / 54.  3.100
   libavcodec     56.  0.100 / 56.  0.100
   libavformat    56.  1.100 / 56.  1.100
   libavdevice    56.  0.100 / 56.  0.100
   libavfilter     5.  0.100 /  5.  0.100
   libswscale      3.  0.100 /  3.  0.100
   libswresample   1.  0.100 /  1.  0.100
   libpostproc    53.  0.100 / 53.  0.100
 Input #0, mpegts, from 'test.ts':
   Duration: 00:09:56.51, start: 1.430756, bitrate: 760 kb/s
   Program 1
     Metadata:
       service_name    : Big Buck Bunny
       service_provider: FFmpeg
     Stream #0:0[0x100]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002),
 yuv420p(tv), 640x360 [SAR 1:1 DAR 16:9], max. 104857 kb/s, 24 fps, 24 tbr,
 90k tbn, 48 tbc
     Stream #0:1[0x101](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 44100 Hz,
 stereo, s16p, 371 kb/s
 [FORMAT]
 start_time=1.430756
 [/FORMAT]

 > Which applications warn about failing lipsync?

 {{{
 $ mediafilesegmenter -t 10 test.mp4 | head -n 3
 Aug 16 2014 12:15:42.587: Using floating point is not backward compatible
 to iOS 4.1 or earlier devices
 Aug 16 2014 12:15:42.588: Processing file /Users/chris/Movies/test.mp4
 Aug 16 2014 12:15:42.602: track 1 of /Users/chris/Movies/test.mp4 contains
 edit list that the media doesn't start at beginning; this may cause
 problems in lip sync
 }}}

 > Do you really see A/V desync with any media player?

 I had a user complaining about it. As it's minimal, you'd need input you
 a) know extremely well and b) is a steady talking head or some such, and I
 don't havesomething like that available.

--
Ticket URL: <https://trac.ffmpeg.org/ticket/3859#comment:2>
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