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Subject: Re: iRiver Codec - RT encoding and Fixed point library

Re: iRiver Codec - RT encoding and Fixed point library

From: Robin V. <>
Date: 2005-07-14

This was my 2 cents suggestion. In a world far far away, I remember
the performance reached by demomakers using fixed point instead of
floating point this was quite amazing, but maybe it's not such a good

Maybe this trick was good for matrix and three dimensions game at the
age where no FPU was available, not for today.


On 7/13/05, <> wrote:
> There may well be some sort of fixed point instructions in certain
> versions of the coldfire. However, not on the CF5249 that H1xx/H3xx use,
> (other than the more simple fractional mode of the EMAC unit, which we are
> already using in all of our codecs).
> If there is a fixed-point version of Shine MP3 encoder already optimised
> for ARM then that is probably a good starting point. I'm not sure of the
> merits of 'emulating' floating point using a fixed-point CPU, however (it
> will either require major rewrites of the code or would just run
> suboptimally - in either case, rewriting to use fixed-point data would
> probably be a necessity)
> d

Received on Thu Jul 14 12:16:25 2005

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