#7169: First chapter of MP4 is always 0
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Reporter: jonata | Type: defect
Status: new | Priority: normal
Component: ffmpeg | Version: 3.4
Keywords: chapters | Blocked By:
Blocking: | Reproduced by developer: 0
Analyzed by developer: 0 |
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Summary of the bug: MP4 files produced on ffmpeg with chapter marks being
applied using ffmetadata always have the first chapter at 0.0
How to reproduce:
Test movie file:
https://archive.org/download/mov-bbb/mov_bbb.mp4
Chapters information (chapters.txt):
{{{
;FFMETADATA1
[CHAPTER]
START=2153000000
END=3100000000
title=First chapter should start at 2 sec
[CHAPTER]
START=3100000000
END=5550000000
title=Second chapter
[CHAPTER]
START=5550000000
END=8653600000
title=Final chapter
}}}
Applying chapters
{{{
ffmpeg -i mov_bbb.mp4 -i chapters.txt -map_chapters 1 -c:a copy -c:v copy
mov_bbb_with_chapters.mp4
}}}
or even specifying Apple text
{{{
ffmpeg -i mov_bbb.mp4 -i chapters.txt -map_chapters 1 -c:a copy -c:v copy
-c:s mov_text mov_bbb_with_chapters.mp4
}}}
returns this output, confirming it is understanding the first chapter as
2sec:
{{{
...
Chapter #0:0: start 2.153000, end 3.100000
Metadata:
title : First chapter should start at 2 sec
...
}}}
but running ffprobe -show_chapters:
{{{
ffprobe -show_chapters mov_bbb_with_chapters.mp4
}}}
confirms that in some way ffmpeg is setting the first chapter as 0.0:
{{{
...
Chapter #0:0: start 0.000000, end 3.100000
Metadata:
title : First chapter should start at 2 sec
...
[CHAPTER]
id=0
time_base=1/1000
start=0
start_time=0.000000
end=3100
end_time=3.100000
TAG:title=First chapter should start at 2 sec
[/CHAPTER]
...
}}}
VLC reads the correct information (it shows the first chapter correctly).
Other players like MPV, MPC, QT, reads it as 0.0.
--
Ticket URL: <https://trac.ffmpeg.org/ticket/7169>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker
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