From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: what is the difference between
 SNDRV_PCM_FMTBIT_S24_LE and SNDRV_PCM_FMTBIT_S24_3LE
Date: Thu, 11 Apr 2013 11:00:44 +0200
Message-ID: <51667BBC.3070609@ladisch.de>
References: <6B947C8AC4195040A8C6876A496C644A082F1EB2@BJ-MAIL-04.vimicro.com>
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To: Zhang wei <zhangwei@vimicro.com>
Cc: alsa-devel@alsa-project.org
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Zhang wei wrote:
> SNDRV_PCM_FORMAT_S24_3LE and SNDRV_PCM_FORMAT_S24_LE.
>
> What is the difference between them?

SNDRV_PCM_FORMAT_S24_3LE stores the 24 in three bytes, and is used only
for USB.

SNDRV_PCM_FORMAT_S24_LE stores the 24 bits in the lower bits of a 32-bit
word, and is almost never used.

Most devices that support 24 bits use SNDRV_PCM_FORMAT_S32_LE, which
stores the sample's bits in the upper bits of a 32-bit word.


Regards,
Clemens