marytts.signalproc.process
Class PhaseVocoder

java.lang.Object
  marytts.util.data.BaseDoubleDataSource
      marytts.util.data.BufferedDoubleDataSource
          marytts.util.data.BlockwiseDoubleDataSource
              marytts.signalproc.process.FrameOverlapAddSource
                  marytts.signalproc.process.PhaseVocoder

All Implemented Interfaces:

DoubleDataSource

public class PhaseVocoder
extends FrameOverlapAddSource

A phase vocoder implementation for time stretching. Phase unwrapping is performed.

Author:

Marc Schröder

Nested Class Summary

class

PhaseVocoder.PhaseUnwrapper

Field Summary

static int	DEFAULT_FRAMELENGTH
protected double	rateChangeFactor

Fields inherited from class marytts.signalproc.process.FrameOverlapAddSource

DEFAULT_WINDOWTYPE, frameProvider, memory, outputWindow, processor

Fields inherited from class marytts.util.data.BlockwiseDoubleDataSource

blockSize

Fields inherited from class marytts.util.data.BufferedDoubleDataSource

buf, dataProcessor, DEFAULT_BUFFERSIZE, readPos, writePos

Fields inherited from class marytts.util.data.BaseDoubleDataSource

dataLength, inputSource

Fields inherited from interface marytts.util.data.DoubleDataSource

NOT_SPECIFIED

Constructor Summary

PhaseVocoder(DoubleDataSource inputSource, int samplingRate, double rateChangeFactor)

Method Summary

int	computeOutputLength(int inputLengthInSamples) Based on the given rate change factor, compute the exact length change factor for a given signal length, based on the current frame length and input/output frame shifts.
protected int	getInputFrameshift(int outputFrameshift)
static void	main(java.lang.String[] args)

Methods inherited from class marytts.signalproc.process.FrameOverlapAddSource

getBlockSize, getNextFrame, hasMoreData, initialise, prepareBlock, readBlock

Methods inherited from class marytts.util.data.BlockwiseDoubleDataSource

readIntoBuffer

Methods inherited from class marytts.util.data.BufferedDoubleDataSource

available, bufferSpaceLeft, compact, currentlyInBuffer, getData, increaseBufferSize

Methods inherited from class marytts.util.data.BaseDoubleDataSource

getAllData, getData, getData, getDataLength

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_FRAMELENGTH

public static final int DEFAULT_FRAMELENGTH

See Also:

Constant Field Values

rateChangeFactor

protected double rateChangeFactor

Constructor Detail

PhaseVocoder

public PhaseVocoder(DoubleDataSource inputSource,
                    int samplingRate,
                    double rateChangeFactor)

Parameters:

inputSource -

frameLength -

samplingRate -

rateChangeFactor - the factor by which to speed up or slow down the source. Values greater than one will speed up, values smaller than one will slow down the original.

Method Detail

getInputFrameshift

protected int getInputFrameshift(int outputFrameshift)

Overrides:

getInputFrameshift in class FrameOverlapAddSource

computeOutputLength

public int computeOutputLength(int inputLengthInSamples)

Based on the given rate change factor, compute the exact length change factor for a given signal length, based on the current frame length and input/output frame shifts. From the illustrations in @see{FrameOverlapAddSource}, it can be seen that for a given frame length f and frame shift s, the length of a signal can be described as l(n) = f + n*s - delta. f is fixed; s is si for input frameshift, so for output frameshift. For a given input length, one can compute n and rest and thus compute the output length.

Returns:

the output length

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception

Throws:

java.lang.Exception