From alsa-devel-owner@alsa.jcu.cz  Fri Mar 13 21:54:04 1998
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	Fri, 13 Mar 1998 21:54:01 +0100
Date: Fri, 13 Mar 1998 21:54:01 +0100 (MET)
From: Jaroslav Kysela <perex@jcu.cz>
To: Alan Robinson <ar@vt.edu>
cc: alsa-devel@alsa.jcu.cz
Subject: Re: library/low-level inner workings
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On Fri, 13 Mar 1998, Alan Robinson wrote:

> >From the api docs:
> 
> Low-Level layer supports these formats:
> 
> #define SND_PCM_SFMT_MU_LAW             0
> #define SND_PCM_SFMT_A_LAW              1
> #define SND_PCM_SFMT_IMA_ADPCM          2
> #define SND_PCM_SFMT_U8                 3
> #define SND_PCM_SFMT_S16_LE             4
> #define SND_PCM_SFMT_S16_BE             5
> #define SND_PCM_SFMT_S8                 6
> #define SND_PCM_SFMT_U16_LE             7
> #define SND_PCM_SFMT_U16_BE             8
> #define SND_PCM_SFMT_MPEG               9
> #define SND_PCM_SFMT_GSM                10
> 
> [.....]
> 
> My question is, how do you intend to support these formats?  Is there an
> already written library out there that can convert those formats into raw
> 16 or 8 bit data?  Or do you expect to have to write that code too?  Where
> I am going with this is that if we are going to need to write the
> conversion code (even if it just means reworking somebody else's code) we
> ought to put it into a separate library.  Then it could be used by more
> than just the driver.  After all, some programs like to be able to modify
> audio data directly, and having a nice translation library would make that
> task easier.

Good idea... Code should be really separated from other code in ALSA
library API... What about to create library 'libsoundconv'?

-----
Jaroslav Kysela <perex@jcu.cz>
Academic Computer Centre, University of South Bohemia
Branisovska 31, C. Budejovice, CZ-370 05 Czech Republic


