[FFmpeg-trac] #4(avformat:new): MP3 file with unsynchronised id3v2 tag is not read correctly

[FFmpeg]

#4: MP3 file with unsynchronised id3v2 tag is not read correctly
----------------------+----------------------
  Reporter:  cehoyos  |      Owner:  michael
      Type:  defect   |     Status:  new
  Priority:  normal   |  Component:  avformat
   Version:  git      |   Keywords:
Blocked By:           |   Blocking:
Reproduced:  1        |   Analyzed:  1
----------------------+----------------------
 (issue 2650)
 FFmpeg does support unsynchronisation in id3v2 tags, but only in tags
 starting with "T". Attached sample is unsynchronised in MCDI tag, making
 it impossible to read the remaining id3v2 tags that can be read if I
 remove the inserted byte (or patch id3v2.c to skip it).

 (Additionally, the OP reported that the VBR tag can not be read in this
 file.)
 {{{
 ffmpeg -i b.mp3
 FFmpeg version git-N-27871-gcc4d3dd, Copyright (c) 2000-2011 the FFmpeg
 developers
   built on Mar  8 2011 20:24:27 with gcc 4.5.2
   configuration: --cc=/usr/local/gcc-4.5.2/bin/gcc --enable-gpl
   libavutil    50. 39. 0 / 50. 39. 0
   libavcodec   52.113. 2 / 52.113. 2
   libavformat  52.102. 0 / 52.102. 0
   libavdevice  52.  3. 0 / 52.  3. 0
   libavfilter   1. 76. 0 /  1. 76. 0
   libswscale    0. 12. 0 /  0. 12. 0
 [mp3 @ 0x11eb440] Header missing
 [mp3 @ 0x11e8650] max_analyze_duration reached
 [mp3 @ 0x11e8650] Estimating duration from bitrate, this may be inaccurate
 Input #0, mp3, from 'b.mp3':
   Metadata:
     title           : Sound Of Letting Go
     artist          : David Guetta & Tocadisco feat. Chris Willis
     album           : One Love
     TYER            : 2009
     track           : 13/16
   Duration: 00:24:16.38, start: 0.000000, bitrate: 32 kb/s
     Stream #0.0: Audio: mp3, 44100 Hz, stereo, s16, 32 kb/s
 At least one output file must be specified
 }}}
 With the 259th byte removed four additional tags are shown:
 {{{
 ffmpeg -i t.mp3
 FFmpeg version git-N-27871-gcc4d3dd, Copyright (c) 2000-2011 the FFmpeg
 developers
   built on Mar  8 2011 20:24:27 with gcc 4.5.2
   configuration: --cc=/usr/local/gcc-4.5.2/bin/gcc --enable-gpl
   libavutil    50. 39. 0 / 50. 39. 0
   libavcodec   52.113. 2 / 52.113. 2
   libavformat  52.102. 0 / 52.102. 0
   libavdevice  52.  3. 0 / 52.  3. 0
   libavfilter   1. 76. 0 /  1. 76. 0
   libswscale    0. 12. 0 /  0. 12. 0
 [mp3 @ 0x11e9710] Header missing
 [mp3 @ 0x11e8650] max_analyze_duration reached
 [mp3 @ 0x11e8650] Estimating duration from bitrate, this may be inaccurate
 Input #0, mp3, from 't.mp3':
   Metadata:
     title           : Sound Of Letting Go
     artist          : David Guetta & Tocadisco feat. Chris Willis
     album           : One Love
     TYER            : 2009
     track           : 13/16
     TLEN            : 225986
     genre           : Bance
     encoded_by      : Exact Audio Copy   (Secure mode)
     encoder         : LAME.EXE -V 2 --vbr-new
   Duration: 00:24:16.38, start: 0.000000, bitrate: 32 kb/s
     Stream #0.0: Audio: mp3, 44100 Hz, stereo, s16, 32 kb/s
 At least one output file must be specified
 }}}

-- 
Ticket URL: <http://avcodec.org/trac/ffmpeg/ticket/4>
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