On Wednesday 21 January 2009 10:00, Takashi Iwai wrote:
At Tue, 20 Jan 2009 17:33:24 +0100,
Diego E. 'Flameeyes' Pettenò wrote:
Jaroslav Kysela perex@perex.cz writes:
Note that front and surround devices does not support automatic sample conversion. Use plug:front, plug:surround40 etc. devices.
Using the correct format, front:IDX should work with two channels sound files, and it doesn't, nor surround40:IDX works with four channels or surround71:IDX with eight channels.
[I'm using IDX because I have it on :1 rather than :0]
I thought plug:front:IDX works, at least on 1.0.19, too...
It does work here on older Alsa.
I think Diego's point though is that 'surround40:IDX' might be expected to be a 4-channel stream, whereas it is as dependant on the hardware as 'hw:IDX' is. In the later case it is clear that the user must provide audio in whatever format/channels the hardware uses. However it is unexpected that eg on ice1712 'surround40:IDX' requires a 10-channel playback stream and ignores 6 of them, and will not play a 4-channel stream.
It is also not symetrical, so if you capture it has to be a 12-channel stream, which it is then not possible to play without using the plug: devices.
Unless I am mistaken...
Alan