README

FastFourierDJB

Modification of FastFourierDJB

author : Milenko Mitrovic
email : dcoder@dsp-worx.de
web : http://dsp-worx.de
date : 24-07-2003

Based on D.J.Bernsteinґs Split Radix FFT v0.76.
http://cr.yp.to/djbfft.html

The contents of this file are used with permission, subject to
the Mozilla Public License Version 1.1 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.mozilla.org/MPL/MPL-1.1.html

Software distributed under the License is distributed on an
"AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
implied. See the License for the specific language governing
rights and limitations under the License.

(C) 2003, 2004 Milenko Mitrovic dcoder@dsp-worx.de

Modifications by Alexey V. Nikitaev email : nikitayev@mail.ru web : https://github.com/nikitayev/ date : 02-10-2015

Sample:

// применим окно Хэмминга for i := 0 to zFFTLength - 1 do zFFT[i].re := GetWindowingValue(zFFT[i].re, i, zFFTLength, TWindowMode.wmHamming);

dspDoFFT(zFFT, zFFTLength, False, True, True, zFFTSwap);

zMaxValue := 0; for i := 0 to (zFFTLength shr 1) - 1 do begin aFFT[i] := FFTSum(zFFT[i].re, zFFT[i].im); end;