From alsa-devel-owner@alsa.jcu.cz  Tue Jan 19 11:16:17 1999
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	Tue, 19 Jan 1999 11:12:43 +0100
Date: Tue, 19 Jan 1999 11:12:43 +0100 (CET)
From: Jaroslav Kysela <perex@jcu.cz>
To: Guenter Geiger <guenter.geiger@psp-vie.be.philips.com>
cc: alsa-devel@alsa.jcu.cz
Subject: RE: hi-res pcm sound support
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On Tue, 19 Jan 1999, Guenter Geiger wrote:

> Id suggest using 32-bit integers -- little endian and big endian version of
> course
> for the API.
> 
> Any conversion to some soundcard internal 24 bit format should be done in the
> driver.
> (this means eventually shifting 8 bits down or swapping bytes)

Note that any conversion si time consuming... I think that the best way is
transfer data to hardware unchanged if possible.

24-bit and 32-bit samples should be probably ok? I really don't know which
data are expected from DSPs or CODECs which supports 16+-bit resolution..

> 
> Guenter
> 
> > -----Original Message-----
> > From: alsa-devel-owner@alsa.jcu.cz
> > [mailto:alsa-devel-owner@alsa.jcu.cz]On Behalf Of Jaroslav Kysela
> > Sent: Tuesday, January 19, 1999 12:56 AM
> > To: Elliot Lee
> > Cc: alsa-devel@alsa.jcu.cz
> > Subject: Re: hi-res pcm sound support
> >
> >
> > On Wed, 13 Jan 1999, Elliot Lee wrote:
> >
> > > Does the ALSA architecture have room for higher resolution
> > (e.g. 24-bit
> > > 96Khz) PCM sound recording and playback? The asound.h that
> > I looked at
> > > only said anything about 8 and 16-bit sound.
> > >
> > > It would be really nice if someone with a professional
> > audio background
> > > would ensure that ALSA has everything needed for pro sound
> > production.
> >
> > It is possible enhance API for more than 16-bit resolution,
> > but as I asked
> > before (without any answer yet): How are 16+-bit samples encoded to
> > stream? How bytesex is used (one or both)?
> >
> > If someone don't send me reply on my questions (or some
> > pointer to pages
> > where is described this issue), I cannot add appropriate extensions to
> > header files.
> >
> > 							Jaroslav
> >
> > -----
> > Jaroslav Kysela <perex@jcu.cz>
> > Academic Computer Centre, University of South Bohemia
> > Branisovska 31, C. Budejovice, CZ-370 05 Czech Republic
> >
> > ------
> > To unsubscribe from <alsa-devel@alsa.jcu.cz> mailing list send message
> > 'unsubscribe' in the body of message to
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> >
> 
> ------
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> 

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


