From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Clemens Ladisch" <cladisch@fastmail.net>
Subject: Re: SNDRV_PCM_FMTBIT_S24_LE vs.
	SNDRV_PCM_FMTBIT_S24_3LE
Date: Tue, 24 Jul 2007 09:03:05 +0200
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To: Timur Tabi <timur@freescale.com>
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dustin@seznam.cz wrote:
> >  What is the difference between SNDRV_PCM_FMTBIT_S24_LE and
> >  SNDRV_PCM_FMTBIT_S24_3LE?
> 
> The asound.h says S24_LE is stored in lower three bytes of four, whereas
> S24_3LE is stored in three bytes total.

To use a sample format with 24 bits stored in the upper three bytes of
four, use S32_LE.  In that case, you have to call
"snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24)" in the PCM open
callback to tell ALSA that some of the lower bits aren't used.


HTH
Clemens