[FFmpeg-trac] #3842(avformat:new): AAC (mp4a) DASH takes abnormally long to detect (~4 - 6s)

[FFmpeg]

#3842: AAC (mp4a) DASH takes abnormally long to detect (~4 - 6s)
---------------------------------+------------------------------------
             Reporter:  viperfx  |                    Owner:
                 Type:  defect   |                   Status:  new
             Priority:  normal   |                Component:  avformat
              Version:  2.2.4    |               Resolution:
             Keywords:  mov      |               Blocked By:
             Blocking:           |  Reproduced by developer:  0
Analyzed by developer:  0        |
---------------------------------+------------------------------------

Comment (by cehoyos):

 I tested the following:
 {{{
 $ time ffmpeg -i videoplayback.mp4
 ffmpeg version N-65479-g7117547 Copyright (c) 2000-2014 the FFmpeg
 developers
   built on Aug 10 2014 13:36:46 with gcc 4.7 (SUSE Linux)
   configuration: --enable-gpl
   libavutil      54.  0.100 / 54.  0.100
   libavcodec     56.  0.100 / 56.  0.100
   libavformat    56.  0.100 / 56.  0.100
   libavdevice    56.  0.100 / 56.  0.100
   libavfilter     5.  0.100 /  5.  0.100
   libswscale      3.  0.100 /  3.  0.100
   libswresample   1.  0.100 /  1.  0.100
   libpostproc    53.  0.100 / 53.  0.100
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'videoplayback.mp4':
   Metadata:
     major_brand     : dash
     minor_version   : 0
     compatible_brands: iso6mp41
     creation_time   : 2014-04-25 14:50:56
   Duration: 00:03:35.03, start: 0.000000, bitrate: 128 kb/s
     Stream #0:0(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo,
 fltp, 125 kb/s (default)
     Metadata:
       creation_time   : 2014-04-25 14:50:56
       handler_name    : SoundHandler
 At least one output file must be specified

 real    0m0.011s
 user    0m0.007s
 sys     0m0.003s
 }}}
 The time spent on analyzing the mov file seems reasonable to me.
 Playback with ffplay starts immediately afaict (see how the process time
 matches the duration):
 {{{
 $ time ffplay -i videoplayback.mp4 -autoexit
 ffplay version N-65479-g7117547 Copyright (c) 2003-2014 the FFmpeg
 developers
   built on Aug 10 2014 13:36:46 with gcc 4.7 (SUSE Linux)
   configuration: --enable-gpl
   libavutil      54.  0.100 / 54.  0.100
   libavcodec     56.  0.100 / 56.  0.100
   libavformat    56.  0.100 / 56.  0.100
   libavdevice    56.  0.100 / 56.  0.100
   libavfilter     5.  0.100 /  5.  0.100
   libswscale      3.  0.100 /  3.  0.100
   libswresample   1.  0.100 /  1.  0.100
   libpostproc    53.  0.100 / 53.  0.100
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'videoplayback.mp4':f=0/0
   Metadata:
     major_brand     : dash
     minor_version   : 0
     compatible_brands: iso6mp41
     creation_time   : 2014-04-25 14:50:56
   Duration: 00:03:35.03, start: 0.000000, bitrate: 128 kb/s
     Stream #0:0(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo,
 fltp, 125 kb/s (default)
     Metadata:
       creation_time   : 2014-04-25 14:50:56
       handler_name    : SoundHandler
  215.02 M-A:  0.000 fd=   0 aq=    0KB vq=    0KB sq=    0B f=0/0

 real    3m35.104s
 user    0m4.030s
 sys     0m2.981s
 }}}
 How can I reproduce the issue?

--
Ticket URL: <https://trac.ffmpeg.org/ticket/3842#comment:3>
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