Re: Java audio applications

[Paul John Leonard <eespjl@xxxxxxxxxx>]

Hi Bill,

rasmusDSP http://rasmusdsp.cvs.sourceforge.net/  has a few useful
processing functions.

Here is the comment in the PitchShift class.

public class PitchShift {
	
	/* CONVERSION TO JAVA BY: Karl Helgason (kalli@xxxxxxxxxxx), 2005 */
	
	/* ***************************************************************************
	 *
	 * NAME: smbPitchShift.cpp
	 * VERSION: 1.1
	 * HOME URL: http://www.dspdimension.com
	 * KNOWN BUGS: none
	 *
	 * SYNOPSIS: Routine for doing pitch shifting while maintaining
	 * duration using the Short Time Fourier Transform.
	 *
	 * DESCRIPTION: The routine takes a pitchShift factor value which is between 0.5
	 * (one octave down) and 2. (one octave up). A value of exactly 1 does not change
	 * the pitch. numSampsToProcess tells the routine how many samples in indata[0...
	 * numSampsToProcess-1] should be pitch shifted and moved to outdata[0 ...
	 * numSampsToProcess-1]. The two buffers can be identical (ie. it can process the
	 * data in-place). fftFrameSize defines the FFT frame size used for the
	 * processing. Typical values are 1024, 2048 and 4096. It may be any value <=
	 * MAX_FFT_FRAME_LENGTH but it MUST be a power of 2. osamp is the STFT
	 * oversampling factor which also determines the overlap between adjacent STFT
	 * frames. It should at least be 4 for moderate scaling ratios. A value of 32 is
	 * recommended for best quality. sampleRate takes the sample rate for the signal 
	 * in unit Hz, ie. 44100 for 44.1 kHz audio. The data passed to the routine in 
	 * indata[] should be in the range [-1.0, 1.0), which is also the output range 
	 * for the data, make sure you scale the data accordingly (for 16bit signed integers
	 * you would have to divide (and multiply) by 32768). 
	 *

cheers Paul.


> Dear List,
> I am looking for a Java application that can do pitch shifting.
> Actually,
> any package of Java audio tools would also be helpful. Thanks in
> advance for any info, Bill D`Angelo
>
>