[FFmpeg-trac] #9098(undetermined:new): mov timebase issue with large subtitle track

[FFmpeg]

#9098: mov timebase issue with large subtitle track
-------------------------------------+-------------------------------------
               Reporter:  dericed    |                  Owner:
                   Type:  defect     |                 Status:  new
               Priority:  normal     |              Component:
                Version:             |  undetermined
  unspecified                        |               Keywords:  mov
             Blocked By:             |               Blocking:
Reproduced by developer:  0          |  Analyzed by developer:  0
-------------------------------------+-------------------------------------
 Summary of the bug:

 I was trying to mux a vtt file into an mov but getting this error:
 {{{
 FATAL error, file duration too long for timebase, this file will not be
 playable with QuickTime. Choose a different timebase with
 -video_track_timescale or a different container format
 }}}
 After trying the timescale suggestion, I realized that the issue is not
 about the video track but about the subtitle track. There's a command to
 generate the error below. AFAICT there's no subtitle_track_timescale and
 I'd rather stick with mov in this case.


 How to reproduce:
 {{{
 ffmpeg -i test.vtt -map 0:s -c:s mov_text -tag:s:s:0 tx3g test.mov
 ffmpeg version git-2021-01-28-ed51890 Copyright (c) 2000-2021 the FFmpeg
 developers
   built with Apple clang version 12.0.0 (clang-1200.0.32.29)
   configuration: --prefix=/usr/local/Cellar/ffmpeg/HEAD-ed51890_9
 --enable-shared --enable-pthreads --enable-version3 --enable-avresample
 --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls
 --enable-gpl --enable-libaom --enable-libbluray --enable-libdav1d
 --enable-libmp3lame --enable-libopus --enable-librav1e --enable-
 librubberband --enable-libsnappy --enable-libsrt --enable-libtesseract
 --enable-libtheora --enable-libvidstab --enable-libvorbis --enable-libvpx
 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2
 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype
 --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-
 libopencore-amrwb --enable-libopenjpeg --enable-librtmp --enable-libspeex
 --enable-libsoxr --enable-videotoolbox --enable-libzmq --enable-libzimg
 --disable-libjack --disable-indev=jack
   libavutil      56. 64.100 / 56. 64.100
   libavcodec     58.119.100 / 58.119.100
   libavformat    58. 65.101 / 58. 65.101
   libavdevice    58. 11.103 / 58. 11.103
   libavfilter     7.100.100 /  7.100.100
   libavresample   4.  0.  0 /  4.  0.  0
   libswscale      5.  8.100 /  5.  8.100
   libswresample   3.  8.100 /  3.  8.100
   libpostproc    55.  8.100 / 55.  8.100
 Input #0, webvtt, from 'test.vtt':
   Duration: N/A, bitrate: N/A
     Stream #0:0: Subtitle: webvtt
 Output #0, mov, to 'test.mov':
   Metadata:
     encoder         : Lavf58.65.101
     Stream #0:0: Subtitle: mov_text (tx3g / 0x67337874)
     Metadata:
       encoder         : Lavc58.119.100 mov_text
 Stream mapping:
   Stream #0:0 -> #0:0 (webvtt (native) -> mov_text (native))
 Press [q] to stop, [?] for help
 FATAL error, file duration too long for timebase, this file will not be
 playable with QuickTime. Choose a different timebase with
 -video_track_timescale or a different container format
 size=    1669kB time=00:35:59.99 bitrate=   6.3kbits/s speed= 301x
 video:0kB audio:0kB subtitle:1047kB other streams:0kB global headers:0kB
 muxing overhead: 59.359367%
 }}}
 Patches should be submitted to the ffmpeg-devel mailing list and not this
 bug tracker.

--
Ticket URL: <https://trac.ffmpeg.org/ticket/9098>
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