[FFmpeg-trac] #5829(undetermined:new): ADPCM SWF wave decode error, but directly decode *.flv right

FFmpeg trac at avcodec.org
Wed Sep 7 10:38:36 EEST 2016


#5829: ADPCM SWF wave decode error, but directly decode *.flv right
-------------------------------------+-------------------------------------
             Reporter:  Guiding.Li   |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:  git-
  undetermined                       |  master
             Keywords:  ADPCM SWF    |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:

 ADPCM SWF wave decode error, but directly decode *.flv right

 % ./ffmpeg -i ~/program/swf_adpcm/mono_11k.flv -vn -acodec copy
 mono_11k_bs.wav
 % ./ffmpeg -i mono_11k_bs.wav mono_11k_pcm.wav
 Got mono_11k_pcm.wav error.

 % ./ffmpeg -i ~/program/swf_adpcm/mono_11k.flv -vn mono_11k_pcm_right.wav
 Got mono_11k_pcm_right.wav right.


 *.flv   ------>    right.wav
 *.flv --> swf.wav -->  error.wav

 Also, use SWF ADPCM encode to a wav, then decode it to PCM, meet error.
 PCM  -->  swf.wav   -->  PCM(error)



 Root cause in my opinion´╝Ü
 SWF adpcm take block_align as once decoded frame_size.
 When decode *.flv, we can get the right frame_size.
 When decode swf.wav get the wrong frame_size.




 How to reproduce:
 {{{
 CMD:
 % ./ffmpeg -i ~/program/swf_adpcm/mono_11k.flv -vn -acodec copy
 mono_11k_bs.wav
 % ./ffmpeg -i mono_11k_bs.wav mono_11k_pcm.wav
 % ./ffmpeg -i ~/program/swf_adpcm/mono_11k.flv -vn mono_11k_pcm_right.wav

 Version:
 From https://git.ffmpeg.org/ffmpeg
    369ed11..ba7be8c  master     -> origin/master
    8887daf..c32ce24  release/2.8 -> origin/release/2.8
    b62191f..3512ed3  release/3.0 -> origin/release/3.0
    4275b27..677ea4a  release/3.1 -> origin/release/3.1
  * [new tag]         n3.0.3     -> n3.0.3
 From https://git.ffmpeg.org/ffmpeg
  * [new tag]         n3.1.3     -> n3.1.3
 Updating 369ed11..ba7be8c


 Log:

 ligd at bjdevel03 ffmpeg $./ffmpeg -i ~/program/swf_adpcm/mono_11k.flv -vn
 -acodec copy mono_11k_bs.wav
 ffmpeg version N-81571-gba7be8c Copyright (c) 2000-2016 the FFmpeg
 developers
   built with gcc 4.4.5 (Debian 4.4.5-8)
   configuration: --prefix=/home/ligd/git/
   libavutil      55. 29.100 / 55. 29.100
   libavcodec     57. 55.101 / 57. 55.101
   libavformat    57. 48.102 / 57. 48.102
   libavdevice    57.  0.102 / 57.  0.102
   libavfilter     6. 60.100 /  6. 60.100
   libswscale      4.  1.100 /  4.  1.100
   libswresample   2.  1.100 /  2.  1.100
 [flv @ 0xa48b260] video stream discovered after head already parsed
 [flv @ 0xa48b260] audio stream discovered after head already parsed
 Input #0, flv, from '/home/ligd/program/swf_adpcm/mono_11k.flv':
   Duration: 00:01:00.46, start: 0.000000, bitrate: 810 kb/s
     Stream #0:0: Video: flv1, yuv420p, 640x352, 12 fps, 12 tbr, 1k tbn
     Stream #0:1: Audio: adpcm_swf, 11025 Hz, mono, s16, 44 kb/s
 [wav @ 0xa4e4b00] Using AVStream.codec to pass codec parameters to muxers
 is deprecated, use AVStream.codecpar instead.
 [wav @ 0xa4e4b00] requested bits_per_coded_sample (16) and actually stored
 (4) differ
 Output #0, wav, to 'mono_11k_bs.wav':
   Metadata:
     ISFT            : Lavf57.48.102
     Stream #0:0: Audio: adpcm_swf (FS[0][0] / 0x5346), 11025 Hz, mono, 44
 kb/s
 Stream mapping:
   Stream #0:1 -> #0:0 (copy)
 Press [q] to stop, [?] for help
 size=     327kB time=00:01:00.46 bitrate=  44.3kbits/s speed=1.73e+03x
 video:0kB audio:327kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: 0.027772%
 ligd at bjdevel03 ffmpeg $
 ligd at bjdevel03 ffmpeg $
 ligd at bjdevel03 ffmpeg $./ffmpeg -i mono_11k_bs.wav mono_11k_pcm.wav
 ffmpeg version N-81571-gba7be8c Copyright (c) 2000-2016 the FFmpeg
 developers
   built with gcc 4.4.5 (Debian 4.4.5-8)
   configuration: --prefix=/home/ligd/git/
   libavutil      55. 29.100 / 55. 29.100
   libavcodec     57. 55.101 / 57. 55.101
   libavformat    57. 48.102 / 57. 48.102
   libavdevice    57.  0.102 / 57.  0.102
   libavfilter     6. 60.100 /  6. 60.100
   libswscale      4.  1.100 /  4.  1.100
   libswresample   2.  1.100 /  2.  1.100
 Guessed Channel Layout for Input Stream #0.0 : mono
 Input #0, wav, from 'mono_11k_bs.wav':
   Metadata:
     encoder         : Lavf57.48.102
   Duration: 00:01:00.46, bitrate: 44 kb/s
     Stream #0:0: Audio: adpcm_swf (FS[0][0] / 0x5346), 11025 Hz, 1
 channels, s16, 44 kb/s
 [wav @ 0xb44c400] Using AVStream.codec to pass codec parameters to muxers
 is deprecated, use AVStream.codecpar instead.
 Output #0, wav, to 'mono_11k_pcm.wav':
   Metadata:
     ISFT            : Lavf57.48.102
     Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 11025 Hz, mono,
 s16, 176 kb/s
     Metadata:
       encoder         : Lavc57.55.101 pcm_s16le
 Stream mapping:
   Stream #0:0 -> #0:0 (adpcm_swf (native) -> pcm_s16le (native))
 Press [q] to stop, [?] for help
 size=    1904kB time=00:01:28.42 bitrate= 176.4kbits/s speed=2.61e+03x
 video:0kB audio:1904kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: 0.004001%

 }}}
 Patches should be submitted to the ffmpeg-devel mailing list and not this
 bug tracker.

--
Ticket URL: <https://trac.ffmpeg.org/ticket/5829>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker


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