[FFmpeg-trac] #5748(ffmpeg:new): M3U8 playback broken after seek in Safari OSX/iOS

[FFmpeg]

#5748: M3U8 playback broken after seek in Safari OSX/iOS
-------------------------------------+-------------------------------------
             Reporter:  bmurphy1976  |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  ffmpeg       |                  Version:
             Keywords:  m3u8         |  unspecified
             Blocking:               |               Blocked By:
Analyzed by developer:  0            |  Reproduced by developer:  0
-------------------------------------+-------------------------------------
 I recently tried upgrading to ffmpeg 3.1 and a number of videos that
 previously worked without issue in Safari on OSX and iOS are now broken
 when remuxed into M3U8 format.

 The specific behavior is that the video starts playing without any issues
 and if you watch from beginning to end there won't be any problem.
 However, if at any point you try to seek (sometimes it might take two or
 three attempts) the video stream will crash.  Playback will either stop
 entirely, or the video stream will crash but audio stream will continue
 playing.

 I ran a git bisect on ffmpeg and this is what I came up with:

 {{{
 # git bisect log
 git bisect start
 # good: [c66f4d1ae64dffaf456d05cbdade02054446f499] Changelog: Fix minor
 formating inconsistency
 git bisect good c66f4d1ae64dffaf456d05cbdade02054446f499
 # bad: [18ce5a4d1b3f87b3b45651401cdf3352de34cfa1] configure: use c++98 for
 c++ files
 git bisect bad 18ce5a4d1b3f87b3b45651401cdf3352de34cfa1
 # good: [bb9f7bf1a21d6e00dcb2afaf94d8f84e410cf89c] Changelog/APIChanges
 Put 3.0 release marker
 git bisect good bb9f7bf1a21d6e00dcb2afaf94d8f84e410cf89c
 # good: [bb9f7bf1a21d6e00dcb2afaf94d8f84e410cf89c] Changelog/APIChanges
 Put 3.0 release marker
 git bisect good bb9f7bf1a21d6e00dcb2afaf94d8f84e410cf89c
 # bad: [36dad146935a500ef6fd7246b5c216f7af26f9db] Merge commit
 'eaeba6f241e0de0e797be10f8fda967ef8489e64'
 git bisect bad 36dad146935a500ef6fd7246b5c216f7af26f9db
 # good: [9f6e63f6f2f289e429c9354c80c21a9dbcd21d1a] avfilter/vf_waveform:
 add >8 bit support for other filters
 git bisect good 9f6e63f6f2f289e429c9354c80c21a9dbcd21d1a
 # bad: [0dfbca73bbb3319af49554f7f844e1d7b8d2192c] Merge commit
 'dc4983d78af2a666461654067d2e5d45b835358a'
 git bisect bad 0dfbca73bbb3319af49554f7f844e1d7b8d2192c
 # skip: [e6053b3b19c070e994a501fe0cc20255d15c4aa8] Merge commit
 'a8068346e48e123f8d3bdf4d64464d81e53e5fc7'
 git bisect skip e6053b3b19c070e994a501fe0cc20255d15c4aa8
 # skip: [3fafde6cbe345d2f84cfe61b94d4a823990969b3] lavc: Add seek_preroll
 to AVCodecParameters
 git bisect skip 3fafde6cbe345d2f84cfe61b94d4a823990969b3
 # good: [4d251723c0a157b77fa9d3c84c74507d399f7254] lavfi: Add coreimage
 filter for GPU based image filtering on OSX.
 git bisect good 4d251723c0a157b77fa9d3c84c74507d399f7254
 # good: [cf4d050b7231d7d96ed4d9a1bfaad87b8981e19d] avformat/wavdec: Remove
 direct s->pb->buffer access
 git bisect good cf4d050b7231d7d96ed4d9a1bfaad87b8981e19d
 # good: [38a6242b271fad4917a1c6201ff61e10160c965b] avformat/mpegts: Remove
 unused argument from analyze()
 git bisect good 38a6242b271fad4917a1c6201ff61e10160c965b
 # bad: [030e69b4dcb92f3b0372c9af1cefba60e9135010] Merge commit
 'a9e1f2cc61cbd5606a087a60565e87923c39de5a'
 git bisect bad 030e69b4dcb92f3b0372c9af1cefba60e9135010
 # bad: [bc91bc1d8b2baa29267b5181d805f5286466cade] Merge commit
 '0705f5960c9d272cef1309c090000865b991c9c7'
 git bisect bad bc91bc1d8b2baa29267b5181d805f5286466cade
 # bad: [6f69f7a8bf6a0d013985578df2ef42ee6b1c7994] Merge commit
 '9200514ad8717c63f82101dc394f4378854325bf'
 git bisect bad 6f69f7a8bf6a0d013985578df2ef42ee6b1c7994
 # good: [571aa7d25edc414c3da9253af8b80508c5275b4b] avcodec/shorten: mark
 as AV_CODEC_CAP_SUBFRAMES
 git bisect good 571aa7d25edc414c3da9253af8b80508c5275b4b
 # good: [60b75186b2c878b6257b43c8fcc0b1356ada218e] avcodec/wmalosslessdec:
 do not discard last frame
 git bisect good 60b75186b2c878b6257b43c8fcc0b1356ada218e
 # skip: [9200514ad8717c63f82101dc394f4378854325bf] lavf: replace
 AVStream.codec with AVStream.codecpar
 git bisect skip 9200514ad8717c63f82101dc394f4378854325bf
 # only skipped commits left to test
 # possible first bad commit: [6f69f7a8bf6a0d013985578df2ef42ee6b1c7994]
 Merge commit '9200514ad8717c63f82101dc394f4378854325bf'
 # possible first bad commit: [9200514ad8717c63f82101dc394f4378854325bf]
 lavf: replace AVStream.codec with AVStream.codecpar
 }}}

 It looks like this is the suspect commit:

 http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=9200514ad8717c63f82101dc394f4378854325bf

 I also took a look at the API change log:

 {{{
 2016-04-14 - afccfaf / b1f01e8 - lavu 55.21.100 / 55.7.0 - hwcontext.h
   Add AVHWFramesConstraints and associated API.

 2016-04-11 - 6f69f7a / 9200514 - lavf 57.33.100 / 57.5.0 - avformat.h
   Add AVStream.codecpar, deprecate AVStream.codec.

 2016-04-02 - e8a9b64 - lavu 55.20.100 - base64.h
   Add AV_BASE64_DECODE_SIZE(x) macro.
 }}}

 and can confirm that revision e8a9b64 does not exhibit any problems.  The
 issue is easily replicated with changeset 6f69f7a/9200514.

 I have a sample input video here (Big Buck Bunny):

 https://s3.amazonaws.com/1d4326f61a9a4ed596de9e1a41d48413/safariissue/input.mp4

 I've already remuxed this video with the two referenced revisions.  This
 was remuxed with 6f69f7a and exhibits the behavior:

 https://s3.amazonaws.com/1d4326f61a9a4ed596de9e1a41d48413/safariissue/6f69f7a/6f69f7a.m3u8

 This was remuxed with e8a9b64 and plays back without issue:

 https://s3.amazonaws.com/1d4326f61a9a4ed596de9e1a41d48413/safariissue/e8a9b64/e8a9b64.m3u8

 The command I used to remux the videos is as follows:

 {{{
 ffmpeg -y -i input.mp4 -c "copy" -map "0" -f "segment" -segment_time "10"
 -vbsf "h264_mp4toannexb" -segment_list_type m3u8 -segment_list
 "e8a9b64/e8a9b64.m3u8" "e8a9b64/e8a9b64.m3u8.%05d.ts"
 }}}

 I can currently reproduce this with Safari Version 9.1.1 (11601.6.17).

--
Ticket URL: <https://trac.ffmpeg.org/ticket/5748>
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