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38 lines
1.8 KiB
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38 lines
1.8 KiB
Plaintext
Subject: FFT for RISC 2.0
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To: macgifts@sumex-aim.stanford.edu
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Enclosure: FFTs-for-RISC-2.sit
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Enclosed is a stuffit archive of version 2.0 of my 'C' source code fft library.
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Very-Fast Fourier Transform routines. Routines are provided for real and complex
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forward and inverse 1d and 2d fourier transforms and 3d complex forward and inverse ffts.
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I coded these to optimize execution speed on Risc processors like the PowerPC.
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All fft sizes must still be a power of two.
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Test programs based on the Numerical Recipes in C routines are provided.
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Also included are some simple applications with source code which time the FFTs.
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See the enclosed read me file for more information.
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Revision version 2.0:
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Rewrote code to rely more on compiler optimization (and be less ugly.)
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Removed restrictions on too small or too large ffts.
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Provided a library extension that manages memory for cosine and bit
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reversed counter tables.
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Added 2d and 3d complex and 2d real ffts.
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Speeded routines for data too large to fit in primary cache.
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Changed most testing from Matlab to Numerical Recipes based (because its cheaper.)
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Changed call parameters (watch out.)
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Revision version 1.21:
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line 126 of rfftTest.c corrected.
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Revisions version 1.2:
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I now store the Nyquest point of the real transform where the 0 for the DC term's
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imaginary part used to be. !! WATCH OUT FOR THIS IF YOU USE rfft !!
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Added the real inverse Fourier transform.
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Revisions version 1.1:
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Re-arranged to put fft routines in a shared library and changed source file name to fftlib.c.
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Removed some ugly optimizations that are no longer needed for CodeWarrier.
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This code is public domain, do anything you want to with it.
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[Moderators- This file should replace ffts-for-risc-121-c.hqx and can be included on any CD]
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