[FFmpeg-trac] #2497(avcodec:open): ALAC encoder adds a burst of white noise

[FFmpeg]

#2497: ALAC encoder adds a burst of white noise
------------------------------------+-----------------------------------
             Reporter:  pneuman     |                    Owner:
                 Type:  defect      |                   Status:  open
             Priority:  normal      |                Component:  avcodec
              Version:  git-master  |               Resolution:
             Keywords:  alac        |               Blocked By:
             Blocking:              |  Reproduced by developer:  1
Analyzed by developer:  0           |
------------------------------------+-----------------------------------
Changes (by cehoyos):

 * status:  new => open
 * reproduced:  0 => 1


Comment:

 {{{
 $ ffmpeg -f s16le -ac 2 -i alac_encoding_error_white_noise_burst.raw
 -acodec alac out.mov -f crc -
 ffmpeg version N-52413-gad56535 Copyright (c) 2000-2013 the FFmpeg
 developers
   built on Apr 23 2013 16:00:56 with gcc 4.7 (SUSE Linux)
   configuration: --enable-gpl --disable-indev=jack
   libavutil      52. 27.100 / 52. 27.100
   libavcodec     55.  6.100 / 55.  6.100
   libavformat    55.  3.100 / 55.  3.100
   libavdevice    55.  0.100 / 55.  0.100
   libavfilter     3. 60.101 /  3. 60.101
   libswscale      2.  2.100 /  2.  2.100
   libswresample   0. 17.102 /  0. 17.102
   libpostproc    52.  3.100 / 52.  3.100
 [s16le @ 0x1957fe0] Estimating duration from bitrate, this may be
 inaccurate
 Guessed Channel Layout for  Input Stream #0.0 : stereo
 Input #0, s16le, from 'alac_encoding_error_white_noise_burst.raw':
   Duration: 00:00:00.30, bitrate: 1411 kb/s
     Stream #0:0: Audio: pcm_s16le, 44100 Hz, stereo, s16, 1411 kb/s
 Output #0, mov, to 'out.mov':
   Metadata:
     encoder         : Lavf55.3.100
     Stream #0:0: Audio: alac (alac / 0x63616C61), 44100 Hz, stereo, s16p,
 128 kb/s
 Output #1, crc, to 'pipe:':
   Metadata:
     encoder         : Lavf55.3.100
     Stream #1:0: Audio: pcm_s16le, 44100 Hz, stereo, s16, 1411 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (pcm_s16le -> alac)
   Stream #0:0 -> #1:0 (pcm_s16le -> pcm_s16le)
 Press [q] to stop, [?] for help
 CRC=0xb3c2238d
 size=      48kB time=00:00:00.37 bitrate=1067.4kbits/s
 video:0kB audio:100kB subtitle:0 global headers:0kB muxing overhead
 -51.431903%
 }}}
 {{{
 $ ffmpeg -i out.mov -f crc -
 ffmpeg version N-52413-gad56535 Copyright (c) 2000-2013 the FFmpeg
 developers
   built on Apr 23 2013 16:00:56 with gcc 4.7 (SUSE Linux)
   configuration: --enable-gpl --disable-indev=jack
   libavutil      52. 27.100 / 52. 27.100
   libavcodec     55.  6.100 / 55.  6.100
   libavformat    55.  3.100 / 55.  3.100
   libavdevice    55.  0.100 / 55.  0.100
   libavfilter     3. 60.101 /  3. 60.101
   libswscale      2.  2.100 /  2.  2.100
   libswresample   0. 17.102 /  0. 17.102
   libpostproc    52.  3.100 / 52.  3.100
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'out.mov':
   Metadata:
     major_brand     : qt
     minor_version   : 512
     compatible_brands: qt
     encoder         : Lavf55.3.100
   Duration: 00:00:00.30, start: 0.000000, bitrate: 1313 kb/s
     Stream #0:0(eng): Audio: alac (alac / 0x63616C61), 44100 Hz, stereo,
 s16p, 1292 kb/s
     Metadata:
       handler_name    : DataHandler
 Output #0, crc, to 'pipe:':
   Metadata:
     major_brand     : qt
     minor_version   : 512
     compatible_brands: qt
     encoder         : Lavf55.3.100
     Stream #0:0(eng): Audio: pcm_s16le, 44100 Hz, stereo, s16, 1411 kb/s
     Metadata:
       handler_name    : DataHandler
 Stream mapping:
   Stream #0:0 -> #0:0 (alac -> pcm_s16le)
 Press [q] to stop, [?] for help
 [alac @ 0x2b76520] invalid element channel count
 Error while decoding stream #0:0: Invalid data found when processing input
 CRC=0x19605977
 size=       0kB time=00:00:00.30 bitrate=   0.4kbits/s
 video:0kB audio:36kB subtitle:0 global headers:0kB muxing overhead
 -99.959310%
 }}}

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2497#comment:3>
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