From mreyes@hanse.de Thu Oct 19 18:24:24 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!hanse!mreyes
From: mreyes@hanse.de (Mikhail Reyes)
Newsgroups: comp.sys.m68k
Subject: [FLAME] Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5
Message-ID: <1995Oct19.182424.5608@hanse.de>
Date: Thu, 19 Oct 1995 18:24:24 GMT
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Can a 1989 Mac IIci decode a 40-minute LP in reasonable time?

A 1024-point radix-2 FFT drops from 142 milliseconds under SANE to just 18 milliseconds using direct FPU instructions.
By passing the -mc68882 compiler flag in Think C, all sin/cos and sqrt operations compile directly to FPU opcodes.

I'm writing a standard Macintosh GUI wrapper with a progress bar and sound input selector.

-- 
Mikhail Reyes
Tape trading list upon request. SASE required for international mail.

From rschneider@demon.co.uk Fri Oct 20 02:23:24 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!demon!rschneider
From: rschneider@demon.co.uk (Rodrigo Schneider)
Newsgroups: comp.sys.m68k
Subject: Re: [FLAME] Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5
Message-ID: <1995Oct20.022324.3389@demon.co.uk>
Date: Fri, 20 Oct 1995 02:23:24 GMT
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In article <1995Oct19.182424.5608@hanse.de>, mreyes@hanse.de (Mikhail Reyes) writes:
> Can a 1989 Mac IIci decode a 40-minute LP in reasonable time?
> A 1024-point radix-2 FFT drops from 142 milliseconds under SANE to just 18 milliseconds using direct FPU instructions.

Beware of System 7.5.1 memory leaks if you allocate large sample buffers in the application heap. Use NewPtrSys instead.

-- 
=== Rodrigo Schneider ===
Dept of Electrical Engineering, Demon Internet Services UK
"The hatch is open. Is anyone listening?"