[Fwd: RE: Ogg Vorbis fixed-point math anyone ?]

Hello,

Thought those involved in the Opie project might find this useful :-)

-----Forwarded Message-----

From: Dan Conti <danc_at_fullplaymedia.com>
To: vorbis-dev_at_xiph.org, Gregor Hoffleit <gregor_at_hoffleit.de>, ipaq_at_handhelds.org
Subject: RE: [vorbis-dev] Re: [iPAQ] Ogg Vorbis fixed-point math anyone ?
Date: 20 Feb 2002 14:55:34 -0800

Actually, we have a integerized version of the vorbis libraries that are
available, royalty free, with a simple attribution requirement. These
libraries are 100% C code and run faster than real time on a cirrus
7312-74mhz processor (arm core). My guess is they should run at about
20-30% cpu utilization on a strongarm/200. Monty has this same code, but
his version doesn't play b4 content real time.

For more information, feel free to contact me off-list.

> -----Original Message-----
> From: owner-vorbis-dev_at_xiph.org [mailto:owner-vorbis-dev_at_xiph.org]On
> Behalf Of Ian Walters
> Sent: Wednesday, February 20, 2002 2:33 PM
> To: Gregor Hoffleit; ipaq_at_handhelds.org
> Cc: vorbis-dev_at_xiph.org
> Subject: [vorbis-dev] Re: [iPAQ] Ogg Vorbis fixed-point math anyone ?
>
>
> Yes and no.
>
> I tried it but not seriously. I only went as far as floating point
> emulation, not trying to understand the algorithms and turn them to
> fixed-point/integer. I have been watching the ogg-vorbis
> lists though, and
> it would seem to be only one part of it that remains to be properly
> integerized. Unfortunately from the sounds of things it
> would take someone
> who really knew what they were doing to transform that last
> bit. I don't
> remember what it was, just that when I Googled for the
> definition what I
> found made very little sense to me.
>
> The emulation proved insufficient as the quality was way,
> way, way down. And
> the normal floating point emulation (e.g. the automatic
> stuff) wasn't fast
> enough.
>
> Ian.
>
> On Thu, 21 Feb 2002 05:38 am, Gregor Hoffleit wrote:
> > A few months ago, there was some discussion about adding fixed-point
> > support for iPAQ's StrongARM to Ogg Vorbis (whether and how it's
> > possible, that is). Has anybody tried this yet ?
> >
> > Gregor
> > _______________________________________________
> > Open Source Software for Compaq iPAQ Handhelds.
> > iPAQ mailing list
> > iPAQ_at_handhelds.org
> > http://handhelds.org/mailman/listinfo/ipaq
> > irc://irc.openprojects.net #ipaq
>
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--
Chris Larson, RHCE, LPIC-1, LCP - aka Kergoth
kergoth at digitalnemesis dot net