Package com.tagtraum.audiokern.math

Class Mauch2010Transform

java.lang.Object

com.tagtraum.audiokern.math.Mauch2010Transform

All Implemented Interfaces:

Transform

public class Mauch2010Transform
extends Object
implements Transform

A constant Q transform that is computed using the algorithm described in Matthias Mauch's 2010 PhD thesis Automatic Chord Transcription from Audio Using Computational Models of Musical Context.

Author:

Hendrik Schreiber

See Also:

Mauch, Matthias: "Automatic Chord Transcription from Audio Using Computational Models of Musical Context", PhD. Thesis, Queen Mary University of London, 2010, Transform

Field Summary

Fields

Modifier and Type	Field	Description
static int	MAX_MIDI
static int	MIN_MIDI

Constructor Summary

Constructors

Constructor	Description
Mauch2010Transform(int fractionsPerSemitone, float sampleRate, int blockSize)	Creates a transformation object.

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object o)
float[][]	fourierToConstantQTransform(float[] real, float[] imaginary)	Converts the result of a fourier transform (see Transform.transform(float[])) into the result of the Mauch2010 transform.
float[]	getFrequencies()
float	getQ()
int	hashCode()
float[][]	inverseTransform(float[] real, float[] imaginary)
String	toString()
float[][]	transform(float[] real)
float[][]	transform(float[] real, float[] imaginary)

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

MIN_MIDI

public static final int MIN_MIDI

See Also:

Constant Field Values

MAX_MIDI

public static final int MAX_MIDI

See Also:

Constant Field Values

Constructor Detail

Mauch2010Transform

public Mauch2010Transform(int fractionsPerSemitone,
                          float sampleRate,
                          int blockSize)

Creates a transformation object.

Parameters:

fractionsPerSemitone - number parts into which each semitone is split up

sampleRate - sample rate

blockSize - processing block size - this is also the length of the internally used FFT.

Method Detail

transform

public float[][] transform(float[] real)
                    throws IllegalArgumentException

Specified by:

transform in interface Transform

Throws:

IllegalArgumentException

inverseTransform

public float[][] inverseTransform(float[] real,
                                  float[] imaginary)
                           throws UnsupportedOperationException

Specified by:

inverseTransform in interface Transform

Throws:

UnsupportedOperationException

transform

public float[][] transform(float[] real,
                           float[] imaginary)
                    throws UnsupportedOperationException

Specified by:

transform in interface Transform

Throws:

UnsupportedOperationException

fourierToConstantQTransform

public float[][] fourierToConstantQTransform(float[] real,
                                             float[] imaginary)

Converts the result of a fourier transform (see Transform.transform(float[])) into the result of the Mauch2010 transform. This method allows you to split the transform into its two parts - the FFT part and the processing of the FFT results.

Parameters:

real - real data (frequency domain)

imaginary - imaginary data (frequency domain)

Returns:

result of this constant Q transform

getQ

public float getQ()

getFrequencies

public float[] getFrequencies()

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object