[FFmpeg-trac] #7553(undetermined:new): start_time / start_pts is wrong for AAC in MOV

[FFmpeg]

#7553: start_time / start_pts is wrong for AAC in MOV
-------------------------------------+-------------------------------------
             Reporter:  shekh        |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:
  undetermined                       |  unspecified
             Keywords:  AAC          |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 (maybe in other containers too)

 AVStream.start_time is set to 0 but the first packet pts is -1024
 If would be helpful if start_time was either correct (-1024) or undefined.
 The value 0 is confusing.

 How to reproduce:
 {{{
 ffmpeg.exe -i src1.avi -vcodec copy -acodec aac -b:a 128k test.mov

 ffmpeg version N-92462-g529debc987 Copyright (c) 2000-2018 the FFmpeg
 developers
   built with gcc 8.2.1 (GCC) 20181017
   configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-
 fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-
 libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-
 amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus
 --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora
 --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp
 --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg
 --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-
 libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex
 --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-
 ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec
 --enable-dxva2 --enable-avisynth
   libavutil      56. 23.101 / 56. 23.101
   libavcodec     58. 39.100 / 58. 39.100
   libavformat    58. 22.100 / 58. 22.100
   libavdevice    58.  6.100 / 58.  6.100
   libavfilter     7. 44.100 /  7. 44.100
   libswscale      5.  4.100 /  5.  4.100
   libswresample   3.  4.100 /  3.  4.100
   libpostproc    55.  4.100 / 55.  4.100
 Guessed Channel Layout for Input Stream #0.1 : stereo
 Input #0, avi, from 'src1.avi':
   Duration: 00:00:05.01, start: 0.000000, bitrate: 3383 kb/s
     Stream #0:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p10le, 124x70,
 1837 kb/s, 23.98 fps, 23.98 tbr, 23.98 tbn, 23.98 tbc
     Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz,
 stereo, s16, 1536 kb/s
 File 'test.mov' already exists. Overwrite ? [y/N] Stream mapping:
   Stream #0:0 -> #0:0 (copy)
   Stream #0:1 -> #0:1 (pcm_s16le (native) -> aac (native))
 Press [q] to stop, [?] for help
 Output #0, mov, to 'test.mov':
   Metadata:
     encoder         : Lavf58.22.100
     Stream #0:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p10le, 124x70,
 q=2-31, 1837 kb/s, 23.98 fps, 23.98 tbr, 11988 tbn, 23.98 tbc
     Stream #0:1: Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo,
 fltp, 128 kb/s
     Metadata:
       encoder         : Lavc58.39.100 aac
 frame=  120 fps=0.0 q=-1.0 Lsize=    1196kB time=00:00:05.01
 bitrate=1954.5kbits/s speed=37.7x
 video:1113kB audio:79kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: 0.336603%
 [aac @ 000000000050b980] Qavg: 178.232
 }}}

 {{{
 ffprobe.exe test.mov -select_streams a:0 -show_packets -show_streams
 >test.txt

 ffprobe version N-92462-g529debc987 Copyright (c) 2007-2018 the FFmpeg
 developers
   built with gcc 8.2.1 (GCC) 20181017
   configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-
 fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-
 libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-
 amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus
 --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora
 --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp
 --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg
 --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-
 libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex
 --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-
 ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec
 --enable-dxva2 --enable-avisynth
   libavutil      56. 23.101 / 56. 23.101
   libavcodec     58. 39.100 / 58. 39.100
   libavformat    58. 22.100 / 58. 22.100
   libavdevice    58.  6.100 / 58.  6.100
   libavfilter     7. 44.100 /  7. 44.100
   libswscale      5.  4.100 /  5.  4.100
   libswresample   3.  4.100 /  3.  4.100
   libpostproc    55.  4.100 / 55.  4.100
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'test.mov':
   Metadata:
     major_brand     : qt
     minor_version   : 512
     compatible_brands: qt
     encoder         : Lavf58.22.100
   Duration: 00:00:05.03, start: 0.000000, bitrate: 1949 kb/s
     Stream #0:0(eng): Video: ffv1 (FFV1 / 0x31564646), yuv422p10le,
 124x70, 1822 kb/s, 23.98 fps, 23.98 tbr, 11988 tbn, 11988 tbc (default)
     Metadata:
       handler_name    : VideoHandler
     Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz,
 stereo, fltp, 128 kb/s (default)
     Metadata:
       handler_name    : SoundHandler
 }}}

--
Ticket URL: <https://trac.ffmpeg.org/ticket/7553>
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