From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: PCM substream
Date: Thu, 09 Aug 2012 14:49:07 +0200
Message-ID: <5023B1C3.40001@ladisch.de>
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To: arun kumar <arun.esd@gmail.com>
Cc: alsa-devel@alsa-project.org
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arun kumar wrote:
> From the last couple of days, I have been trying to understand the Linux
> Alsa Subsystem.I have read the Alsa Driver API and Application API's. But I
> could not understand the concept of PCM substreams,

A PCM stream has one or more substreams.  Multiple substreams are used when
the hardware can mix them together for one output.  This was used in old
wavetable sound cards; nowadays, you almost always have one substream.


Regards,
Clemens