[MPlayer-users] Audio click when speed changed

[Chris Crochet]

On Sun, May 18, 2014 at 3:08 AM, Reimar Döffinger <Reimar.Doeffinger at gmx.de>
wrote:
> Sorry, I just can't hear it.
> You should always provide full command-line and full MPlayer output.
> It might be caused by some other audio filters you are using.
...
> Well, I can offer a patch for scaletempo to resolve a theoretical
> problem, but as said I can't hear anything that could be called a
> click".

Thank you for looking into this.  Scaletempo doesn't appear to be the issue.

I just performed another test with a freshly installed MPlayer, Windows
release binary, executing the following command-line:

  mplayer \test1.avi -ao pcm:file=test1.wav > test1.txt

No scaletempo, and also eliminated Windows-specific audio output drivers
since you're using ALSA.  Test1.avi in this case is the movie "9".  It
begins with a few seconds of silence.  Then a sound slowly fades in, which
is almost sinewave at the start.  This has been my normal test file, since
the clicking is very obvious within these first few seconds, making it
easier to run repeated tests; though I've tried many other files and they
all do it.  I alternately pressed [ and ] a bunch of times for about 20
seconds, then exited MPlayer.

Loading test1.wav in a sound editor, I was able to hear the clicks, then
visually examine them.  It appears small portions (a few ms) of audio from
a few seconds prior are being inserted into, or replacing, what should be
playing.

During playback, the following were output to stderr, which appeared in the
console rather than being redirected to test1.txt:

  Requested audio codec family [mpg123] (afm=mpg123) not available.
  Enable it at compilation.
  [VD_FFMPEG] DRI failure.

And the stdout:

--- test1.txt contents begin ---

MPlayer sherpya-r37199+g5e95551-4.9 (C) 2000-2014 MPlayer Team

Playing \test1.avi.
libavformat version 55.37.102 (internal)
AVI file format detected.
[aviheader] Video stream found, -vid 0
[aviheader] Audio stream found, -aid 1
VIDEO:  [xvid]  640x368  24bpp  23.976 fps  1199.3 kbps (146.4 kbyte/s)
Clip info:
 Software: Lavf51.12.1
Load subtitles in \
Load subtitles in C:/Program Files/MPlayer/mplayer/sub/
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
libavcodec version 55.60.103 (internal)
Selected video codec: [ffodivx] vfm: ffmpeg (FFmpeg MPEG-4)
==========================================================================
==========================================================================
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
AUDIO: 48000 Hz, 2 ch, floatle, 128.0 kbit/4.17% (ratio: 16000->384000)
Selected audio codec: [ffmp3float] afm: ffmpeg (FFmpeg MPEG layer-3 audio)
==========================================================================
[AO PCM] File: test1.wav (WAVE)
PCM: Samplerate: 48000Hz Channels: Stereo Format floatle
[AO PCM] Info: Faster dumping is achieved with -benchmark -vc null -vo null
-ao pcm:fast
[AO PCM] Info: To write WAVE files use -ao pcm:waveheader (default).
AO: [pcm] 48000Hz 2ch floatle (4 bytes per sample)
Starting playback...
Movie-Aspect is 1.74:1 - prescaling to correct movie aspect.
VO: [directx] 640x368 => 640x368 Planar YV12

Exiting... (Quit)

--- test1.txt contents end ---

Hope that helps.  I will provide any additional info, or run any further
tests, in my power to perform.