[MPlayer-users] Mono stream change in behaviour

[Neil Sleightholm]

There was a change made to mplayer.c v1.842 by reimar that has changed
the behaviour of mplayer and contradicts the documentation. With the
1.0pre7 version mono streams were converted to 2 channels:

========================================================================
==
Checking audio filter chain for 44100Hz/1ch/s16le ->
44100Hz/2ch/s16le...
AF_pre: 44100Hz/1ch/s16le
[AO PCM] File: r2.wav (WAVE)
PCM: Samplerate: 44100Hz Channels: Stereo Format s16le
[AO PCM] Info: fastest dumping is achieved with -vc dummy -vo null
PCM: Info: to write WAVE files use -waveheader (default).
AO: [pcm] 44100Hz 2ch s16le (2 bps)
Building audio filter chain for 44100Hz/1ch/s16le ->
44100Hz/2ch/s16le...


But now mono streams remain 1 channel:

========================================================================
==
Building audio filter chain for 44100Hz/1ch/s16le -> 0Hz/0ch/??...
[AO PCM] File: r2.wav (WAVE)
PCM: Samplerate: 44100Hz Channels: Mono Format s16le
[AO PCM] Info: fastest dumping is achieved with -vc dummy -vo null
PCM: Info: to write WAVE files use -ao pcm:waveheader (default).
AO: [pcm] 44100Hz 1ch s16le (2 B/s)
Building audio filter chain for 44100Hz/1ch/s16le ->
44100Hz/1ch/s16le...


In the documentation for the -channel option it says: "Change the
number of playback channels (default: 2)." and "unless mixing from mono
to stereo, then the mono channel is repeated in both output channels".

In my application of mplayer this can cause the output to be played
back a double speed. I can fix this by using the "-channels 2" option
but I would prefer to see the old default restored.

Neil