From mboxrd@z Thu Jan  1 00:00:00 1970
From: dE <de.techno@gmail.com>
Subject: Re: What are subdevices?
Date: Tue, 28 Oct 2014 08:47:26 +0530
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References: <544CAD55.8070605@gmail.com> <544CBACF.2080702@ladisch.de>
 <544CC58C.3080800@gmail.com> <544EA125.80909@ladisch.de>
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On 10/28/14 01:16, Clemens Ladisch wrote:
> dE wrote:
>> typically cards have a single analog device but support multichannel
>> output. So how does this work at the software level? If ALSA can't
>> send multiple streams of audio to one device, then how does ALSA send
>> separate output to different channels of the device?
> The channels are not separate.  For a stereo devices, the samples are
> arranged like LRLRLRLRLR...; for more channels, there are more
> interleaved values: 123456123456123456123456...
>
>
> Regards,
> Clemens
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So it's with the encoding of the PCM.

Thank you so much for the response! I'll blog about this in my ALSA doc.