Hi Takashi, Thanks for trying to help us with trying to resolve http://bugzilla.gnome.org/show_bug.cgi?id=410403.
I tested a bit with a 6-channel .wav file and aplay. It seems it shows the same issues that we are seeing in GStreamer. Namely that if I try:
aplay -D front dust51.wav Playing WAVE 'dust51.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Channels 6 aplay: set_params:905: Channels count non available
It correctly tells me that it doesn't support outputting this many channels. This is fine for GStreamer as it allows our negotiation to plug in a downmixing element.
However if I do: aplay -D default dust51.wav Playing WAVE 'dust51.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Channels 6
It plays out the 'front' channels, but the remainders just get lost. So when outputting to default neither do alsa downmix by itself or fail telling you that you don't have the needed 6 channels available.
Since Jan brought up the issue of behaviour differences between plug:surround51 ad surround51 I thought I give you the output of that too.
aplay -D surround51:0 dust51.wav Playing WAVE 'dust51.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Channels 6 aplay: set_params:878: Broken configuration for this PCM: no configurations available
aplay -D plug:surround51:0 dust51.wav Playing WAVE 'dust51.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Channels 6 ALSA lib pcm_params.c:2152:(snd_pcm_hw_refine_slave) Slave PCM not usable aplay: set_params:878: Broken configuration for this PCM: no configurations available
Christian
On Thu, 2007-03-29 at 12:52 +0200, Takashi Iwai wrote:
At Wed, 28 Mar 2007 17:52:21 +0200, Christian F.K. Schaller wrote:
Hi, We are still having issues resolving how to deal with Surround sound and ALSA in GStreamer. If anyone knowledgeable about ALSA would be willing to comment on this bug: http://bugzilla.gnome.org/show_bug.cgi?id=410403
We would much appreciate it.
Not sure what actually the code is doing, but does simply aplay work on that system?
% aplay -D surround51:0 foo.wav
or
% aplay -D plug:surround51:0 foo.wav
The 5.1 output is sensible to devices, so it's helpful to know what hardware is used, too.
Takashi