com.tagtraum.jipes.math

Class ConstantQTransformFactory

java.lang.Object

com.tagtraum.jipes.math.ConstantQTransformFactory

public abstract class ConstantQTransformFactory
extends Object

Factory for Constant-Q-Transforms. Using the factory allows for sliding-in a faster, perhaps native implementation.

In order to use a factory other than the default factory, you need to specify its classname with the system property com.tagtraum.jipes.math.ConstantQTransformFactory.

The default implementation is equivalent to the one described by Brown and Puckette in their 1992 paper An Efficient Algorithm for the Calculation of a Constant Q Transform.

Date: 5/16/11

Author:

Hendrik Schreiber

See Also:

Brown, J.C. and Puckette, M.S. (1992). "An Efficient Algorithm for the Calculation of a Constant Q Transform", J. Acoust. Soc. Am. 92, 2698-2701. (1992), Matlab implementation by Benjamin Blankertz

Field Summary

Fields

Modifier and Type	Field and Description
static float	DEFAULT_THRESHOLD
static String	FACTORYCLASS_PROPERTY_NAME

Constructor Summary

Constructors

Constructor and Description
ConstantQTransformFactory()

Method Summary

Modifier and Type	Method and Description
abstract Transform	create(float minFreq, float maxFreq, int binsPerOctave, float sampleRate, float threshold) Creates an instance of the constant-Q-transform.
static ConstantQTransformFactory	getInstance() Creates a factory for Constant Q Transform objects.

Methods inherited from class java.lang.Object

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

Field Detail

FACTORYCLASS_PROPERTY_NAME

public static final String FACTORYCLASS_PROPERTY_NAME

DEFAULT_THRESHOLD

public static final float DEFAULT_THRESHOLD

See Also:

Constant Field Values

Constructor Detail

ConstantQTransformFactory

public ConstantQTransformFactory()

Method Detail

getInstance

public static ConstantQTransformFactory getInstance()

Creates a factory for Constant Q Transform objects.

Returns:

factory instance

create

public abstract Transform create(float minFreq,
                                 float maxFreq,
                                 int binsPerOctave,
                                 float sampleRate,
                                 float threshold)

Creates an instance of the constant-Q-transform.

Parameters:

minFreq - min frequency

maxFreq - max frequency

binsPerOctave - total bins per octave

sampleRate - sample rate

threshold - magnitude threshold used for creating the sparse matrix used in the kernel - see DEFAULT_THRESHOLD

Returns:

Constant Q transform instance