[FFmpeg-trac] #2504(avdevice:new): Audio glitches and distortion when recording alsa

[FFmpeg]

#2504: Audio glitches and distortion when recording alsa
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             Reporter:  MrNice      |                    Owner:
                 Type:  defect      |                   Status:  new
             Priority:  important   |                Component:  avdevice
              Version:  git-master  |               Resolution:
             Keywords:  regression  |               Blocked By:
             Blocking:              |  Reproduced by developer:  0
Analyzed by developer:  0           |
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Comment (by MrNice):

 I did the change // saved it and $ ./configure && make.
 {{{
 $ ./ffmpeg -f alsa -ac 2 -i hw:0,0 -y -t 120 out.wav
 ffmpeg version N-54228-g42bd0cd Copyright (c) 2000-2013 the FFmpeg
 developers
   built on Jun 27 2013 15:15:45 with gcc 4.4.7 (GCC) 20120313 (Red Hat
 4.4.7-3)
   configuration:
   libavutil      52. 37.101 / 52. 37.101
   libavcodec     55. 17.100 / 55. 17.100
   libavformat    55. 10.100 / 55. 10.100
   libavdevice    55.  2.100 / 55.  2.100
   libavfilter     3. 77.101 /  3. 77.101
   libswscale      2.  3.100 /  2.  3.100
   libswresample   0. 17.102 /  0. 17.102
 Guessed Channel Layout for  Input Stream #0.0 : stereo
 Input #0, alsa, from 'hw:0,0':
   Duration: N/A, start: 1372346284.750455, bitrate: 1536 kb/s
     Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
 Output #0, wav, to 'out.wav':
   Metadata:
     ISFT            : Lavf55.10.100
     Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz,
 stereo, s16, 1536 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (pcm_s16le -> pcm_s16le)
 Press [q] to stop, [?] for help
 size=    8352kB time=00:00:44.54 bitrate=1536.0kbits/s
 video:0kB audio:8352kB subtitle:0 global headers:0kB muxing overhead
 0.000935%
 }}}
 I recorded 2x 120seconds files.
 First has 31 tics, second has 26 tics, this is more than previously, but
 no distortion.
 I did records with music and there are lot of tics, almost like a vinyl
 record.
 This is not linked to the output level of the player nor the input level
 of the sound preference.
 This looks link to the density of the sound if I cut suddenly the player,
 4 or 5 tics occur in the half second after in the silence.
 If you want a sample let me know.
 This in not acceptable but this is not the bug I had when I open the
 thread. Maybe there is 2 different bugs.

 Sorry but I will have to re-start few steps back, maybe at the beginning.
 Do you agree to lead me?
 I hope I don't spend too much of your time.

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2504#comment:103>
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