amos-zq / pkmfft Goto Github PK

 *  Real FFT wraper for Apple's Accelerate Framework
 *  and STFT implementation making use of Apple's Accelerate Framework (pkmFFT)
 *
 *  Created by Parag K. Mital - http://pkmital.com 
 *  Contact: [email protected]
 *
 *  Copyright 2011 Parag K. Mital. All rights reserved.
 * 
 *	Permission is hereby granted, free of charge, to any person
 *	obtaining a copy of this software and associated documentation
 *	files (the "Software"), to deal in the Software without
 *	restriction, including without limitation the rights to use,
 *	copy, modify, merge, publish, distribute, sublicense, and/or sell
 *	copies of the Software, and to permit persons to whom the
 *	Software is furnished to do so, subject to the following
 *	conditions:
 *	
 *	The above copyright notice and this permission notice shall be
 *	included in all copies or substantial portions of the Software.
 *
 *	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,	
 *	EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 *	OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 *	NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 *	HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 *	WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 *	FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 *	OTHER DEALINGS IN THE SOFTWARE.
 *
 *  Additional resources: 
 *      http://developer.apple.com/library/ios/#documentation/Accelerate/Reference/vDSPRef/Reference/reference.html
 *      http://developer.apple.com/library/ios/#documentation/Performance/Conceptual/vDSP_Programming_Guide/SampleCode/SampleCode.html
 *      http://stackoverflow.com/questions/3398753/using-the-apple-fft-and-accelerate-framework
 *      http://stackoverflow.com/questions/1964955/audio-file-fft-in-an-os-x-environment
 *     
 *
 *  This code is a very simple interface for Accelerate's fft/ifft code.
 *  It was built out of hacking Maximilian (Mick Grierson and Chris Kiefer) and
 *  the above mentioned resources for performing a windowed FFT which could
 *  be used underneath of an STFT implementation
 *
 *  FFT Usage:
 *
 *  // be sure to either use malloc or __attribute__ ((aligned (16))
 *  float *sample_data = (float *) malloc (sizeof(float) * 4096);
 *  float *allocated_magnitude_buffer =  (float *) malloc (sizeof(float) * 2048);
 *  float *allocated_phase_buffer =  (float *) malloc (sizeof(float) * 2048);
 *
 *  pkmFFT *fft;
 *  fft = new pkmFFT(4096);
 *  fft.forward(0, sample_data, allocated_magnitude_buffer, allocated_phase_buffer);
 *  fft.inverse(0, sample_data, allocated_magnitude_buffer, allocated_phase_buffer);
 *  delete fft;
 *
 *
 *  STFT Usage:
 *  // be sure to either use malloc or __attribute__ ((aligned (16))
 *  size_t buffer_size = 4096;
 *  float *sample_data = (float *) malloc (sizeof(float) * buffer_size);
 *  pkm::Mat magnitude_matrix, phase_matrix;
 *
 *  pkmSTFT *stft;
 *  stft = new pkmSTFT(512);
 *  stft.STFT(sample_data, buffer_size, magnitude_matrix, phase_matrix);
 *  fft.ISTFT(sample_data, buffer_size, magnitude_matrix, phase_matrix);
 *  delete stft;