[FFmpeg-trac] #4998(avformat:new): m4a files created by FFmpeg aren't supported by SanDisk Clip Sport/Jam.

[FFmpeg]

#4998: m4a files created by FFmpeg aren't supported by SanDisk Clip Sport/Jam.
-------------------------------------+------------------------------------
             Reporter:  bat999       |                    Owner:
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:  avformat
              Version:  unspecified  |               Resolution:
             Keywords:  aac mov      |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+------------------------------------

Comment (by ubitux):

 Replying to [comment:14 bat999]:
 > Yes, ff.m4a doesn't play and av.m4a does play.
 > ffmpeg -i /tmp/sine.m4a -c copy -skip_iods no -use_editlist no
 /tmp/ff.m4a
 > avconv -i /tmp/sine.m4a -c copy /tmp/av.m4a
 >

 Interesting. So, so far the only two remaining obvious differences I can
 notice are that the {{{udta}}} tag is slightly different, but more
 importantly the {{{stco}}} table is completely different:

 avconv:
 {{{
 0000000000000000|           24     ftyp (66747970) major_brand=[M4A ]
 minor_version=512
 0000000000000018|            8     free (66726565)
 0000000000000020|         233K     mdat (6D646174)
 000000000003a7cb|           5K     moov (6D6F6F76)
 000000000003a7d3|          108         mvhd (6D766864) v=0 creat=0 edit=0
 ts=1000 duration=15047
 000000000003a83f|           24         iods (696F6473)
 000000000003a857|           5K         trak (7472616B)
 000000000003a85f|           92             tkhd (746B6864) v=0 creat=0
 edit=0 trackID=1 duration=15047
 000000000003a8bb|           5K             mdia (6D646961)
 000000000003a8c3|           32                 mdhd (6D646864) v=0 creat=0
 edit=0 ts=44100 duration=663548
 000000000003a8e3|           45                 hdlr (68646C72) soun
 000000000003a910|           5K                 minf (6D696E66)
 000000000003a918|           16                     smhd (736D6864)
 000000000003a928|           36                     dinf (64696E66)
 000000000003a930|           28                         dref (64726566)
 000000000003a94c|           5K                     stbl (7374626C)
 000000000003a954|          106                         stsd (73747364)
 mp4a
 000000000003a9be|           32                         stts (73747473)
 2 entries
 000000000003a9de|           28                         stsc (73747363)
 1 entry
 000000000003a9fa|           2K                         stsz (7374737A)
 647 entries (size=0)
 000000000003b42a|           2K                         stco (7374636F)
 647 entries
 000000000003be56|           95         udta (75647461)
 }}}

 ffmpeg:
 {{{
 0000000000000000|           24     ftyp (66747970) major_brand=[M4A ]
 minor_version=512
 0000000000000018|            8     free (66726565)
 0000000000000020|         233K     mdat (6D646174)
 000000000003a7cb|           3K     moov (6D6F6F76)
 000000000003a7d3|          108         mvhd (6D766864) v=0 creat=0 edit=0
 ts=1000 duration=15047
 000000000003a83f|           24         iods (696F6473)
 000000000003a857|           2K         trak (7472616B)
 000000000003a85f|           92             tkhd (746B6864) v=0 creat=0
 edit=0 trackID=1 duration=15047
 000000000003a8bb|           2K             mdia (6D646961)
 000000000003a8c3|           32                 mdhd (6D646864) v=0 creat=0
 edit=0 ts=44100 duration=663548
 000000000003a8e3|           45                 hdlr (68646C72) soun
 000000000003a910|           2K                 minf (6D696E66)
 000000000003a918|           16                     smhd (736D6864)
 000000000003a928|           36                     dinf (64696E66)
 000000000003a930|           28                         dref (64726566)
 000000000003a94c|           2K                     stbl (7374626C)
 000000000003a954|          106                         stsd (73747364)
 mp4a
 000000000003a9be|           32                         stts (73747473)
 2 entries
 000000000003a9de|           28                         stsc (73747363)
 1 entry
 000000000003a9fa|           2K                         stsz (7374737A)
 647 entries (size=0)
 000000000003b42a|           20                         stco (7374636F)
 1 entry
 000000000003b43e|           98         udta (75647461)
 }}}

 We need to investigate why our stco contains only one entry.

--
Ticket URL: <https://trac.ffmpeg.org/ticket/4998#comment:15>
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