Download ffts-for-risc-2-c.hqx (161,947 KB)
From: green_jt@VSDEC.Npt.NUWC.Navy.Mil
Subject: FFTs-for-RISC-2-c
Enclosed is a stuffit archive of version 2.0 of my 'C' source code fft
library.
Very-Fast Fourier Transform routines. Routines are provided for real
and complex forward and inverse 1d and 2d fourier transforms and 3d
complex forward and inverse ffts. I coded these to optimize execution
speed on Risc processors like the PowerPC. All fft sizes must still be a
power of two. Test programs that use the Numerical Recipes in C routines
are provided. Also included are some simple applications with source
code which time the FFTs. See the enclosed read me file for more
information.
Revision version 2.0:
Rewrote code to rely more on compiler optimization (and be a bit less
ugly.)
Removed restrictions on too small or too large ffts.
Provided a library extension that manages memory for cosine and bit
reversed counter tables.
Added 2d and 3d complex and 2d real ffts.
Speeded routines for data too large to fit in primary cache.
Changed most testing from Matlab to Numerical Recipes based (because
you can buy it for less.)
Changed call parameters (watch out.)
Revision version 1.21:
line 126 of rfftTest.c corrected.
Revisions version 1.2:
I now store the Nyquest point of the real transform where the 0
for the DC term's
imaginary part used to be. !! WATCH OUT FOR THIS IF YOU USE rfft !!
Added the real inverse Fourier transform.
Revisions version 1.1:
Re-arranged to put fft routines in a shared library and changed
source file name to fftlib.c.
Removed some ugly optimizations that are no longer needed for
CodeWarrier.
This code is public domain, do anything you want to with it.
- John Green