From ekim@kiae.su Mon Jan 15 19:48:09 1996
Path: ashpoly!cascade!brgate!saturno!kiae!ekim
From: ekim@kiae.su (Emi Kim)
Newsgroups: comp.sys.m68k
Subject: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5
Message-ID: <1996Jan15.194809.9379@kiae.su>
Date: Mon, 15 Jan 1996 19:48:09 GMT
Organization: Kurchatov Institute of Atomic Energy, Moscow
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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.

-- 
Emi Kim
Tape trading list upon request. SASE required for international mail.

From bivanov@berkeley.edu Mon Jan 15 21:25:09 1996
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!berkeley!bivanov
From: bivanov@berkeley.edu (Brian Ivanov)
Newsgroups: comp.sys.m68k
Subject: Re: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5
Message-ID: <1996Jan15.212509.2907@berkeley.edu>
Date: Mon, 15 Jan 1996 21:25:09 GMT
References: <1996Jan15.194809.9379@kiae.su>
Organization: UC Berkeley Department of EECS
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In article <1996Jan15.194809.9379@kiae.su>, ekim@kiae.su (Emi Kim) writes:
> Can a 1989 Mac IIci decode a 40-minute LP in reasonable time?

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

-- 
Brian Ivanov
Tape trading list upon request. SASE required for international mail.

From snovak@delphi.com Wed Jan 17 19:42:09 1996
Path: ashpoly!cascade!transat!sunet!nordrelay!delphi!snovak
From: snovak@delphi.com (Steve Novak)
Newsgroups: comp.sys.m68k
Subject: Re: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5
Message-ID: <1996Jan17.194209.6045@delphi.com>
Date: Wed, 17 Jan 1996 19:42:09 GMT
References: <1996Jan15.194809.9379@kiae.su>
Organization: Delphi Internet Services
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In article <1996Jan15.194809.9379@kiae.su>, ekim@kiae.su (Emi Kim) 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.

The 68040 on the Quadra is a monster -- the on-chip FPU executes FFT butterflies in less than 4 milliseconds.

-- 
Steve Novak | snovak@delphi.com
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"Keep the channels open."