marf.FeatureExtraction.FFT
Class FFT

java.lang.Object
  marf.Storage.StorageManager
      marf.FeatureExtraction.FeatureExtraction
          marf.FeatureExtraction.FFT.FFT

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, IFeatureExtraction, IStorageManager

public class FFT
extends FeatureExtraction

Class FFT implements Fast Fourier Transform.

$Id: FFT.java,v 1.55 2006/12/28 06:01:57 mokhov Exp $

Since:

0.0.1

Version:

$Revision: 1.55 $

Author:

Stephen Sinclair, Serguei Mokhov

See Also:

Serialized Form

Field Summary

static int	DEFAULT_CHUNK_SIZE Default number (1024) of doubles per chunk in the window.
protected int	iChunkSize FFT chunk size.

Fields inherited from class marf.FeatureExtraction.FeatureExtraction

adFeatures, oFeatureSet, oPreprocessing

Fields inherited from class marf.Storage.StorageManager

bDumpOnNotFound, iCurrentDumpMode, oObjectToSerialize, strFilename

Fields inherited from interface marf.FeatureExtraction.IFeatureExtraction

MARF_INTERFACE_CODE_REVISION

Fields inherited from interface marf.Storage.IStorageManager

DUMP_BINARY, DUMP_CSV_TEXT, DUMP_GZIP_BINARY, DUMP_HTML, DUMP_SQL, DUMP_XML, MARF_INTERFACE_CODE_REVISION, STORAGE_FILE_EXTENSIONS

Constructor Summary

FFT(IPreprocessing poPreprocessing)
FFT Constructor.

Method Summary

boolean	extractFeatures() FFT Implementation of extractFeatures().
boolean	extractFeatures(double[] padSampleData) Extracts features from the provided sample array.
protected boolean	extractFeaturesImplementation(Sample poSample) Does the actual business logic of the FFT feature extraction.
int	getChunkSize() Allows getting the current chunk size.
static java.lang.String	getMARFSourceCodeRevision() Returns source code revision information.
int	setChunkSize(int piChunkSize) Allows setting a non-default chunk size.

Methods inherited from class marf.FeatureExtraction.FeatureExtraction

backSynchronizeObject, clone, getFeaturesArray, getPreprocessing, setPreprocessing

Methods inherited from class marf.Storage.StorageManager

dump, dumpBinary, dumpCSV, dumpGzipBinary, dumpHTML, dumpSQL, dumpXML, enableDumpOnNotFound, equals, getDefaultExtension, getDefaultExtension, getDumpMode, getFilename, getObjectToSerialize, hashCode, restore, restoreBinary, restoreCSV, restoreGzipBinary, restoreHTML, restoreSQL, restoreXML, setDumpMode, setFilename, toString

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_CHUNK_SIZE

public static final int DEFAULT_CHUNK_SIZE

Default number (1024) of doubles per chunk in the window. Feature vector will be half of the chunk size.

See Also:

Constant Field Values

iChunkSize

protected int iChunkSize

FFT chunk size. Must be a power of 2.

Since:

0.3.0.4

Constructor Detail

FFT

public FFT(IPreprocessing poPreprocessing)

FFT Constructor.

Parameters:

poPreprocessing - Preprocessing module reference

Throws:

java.lang.ClassCastException - if a feature extraction module parameter supplied and is not of type Integer

java.lang.IllegalArgumentException - if the chunk size parameter is less than 1 or not a power of 2

Method Detail

extractFeatures

public final boolean extractFeatures()
                              throws FeatureExtractionException

FFT Implementation of extractFeatures(). Sample is taken from an IPreprocessing module from the pipeline.

Specified by:

extractFeatures in interface IFeatureExtraction

Overrides:

extractFeatures in class FeatureExtraction

Returns:

true if there were features extracted, false otherwise

Throws:

FeatureExtractionException - in case of any errors while doing stuff

See Also:

IFeatureExtraction.extractFeatures()

extractFeatures

public final boolean extractFeatures(double[] padSampleData)
                              throws FeatureExtractionException

Extracts features from the provided sample array.

Parameters:

padSampleData - the sample to extract features from

Returns:

boolean true if there were features extracted, false otherwise

Throws:

FeatureExtractionException - if there was an error while extracting features

Since:

0.3.0.6

See Also:

IFeatureExtraction.extractFeatures(double[])

extractFeaturesImplementation

protected final boolean extractFeaturesImplementation(Sample poSample)
                                               throws FeatureExtractionException

Does the actual business logic of the FFT feature extraction.

Parameters:

poSample - sample to extract features from

Returns:

true if there were features extracted, false otherwise

Throws:

FeatureExtractionException - in case of any errors while doing stuff

Since:

0.3.0.6

setChunkSize

public int setChunkSize(int piChunkSize)

Allows setting a non-default chunk size. Must be a power of 2.

Parameters:

piChunkSize - new chunk size

Returns:

the old value of the chunk size (in case some callers are interested in backing it up)

Throws:

java.lang.IllegalArgumentException - if the chunk size parameter is less than 1 or not a power of 2

Since:

0.3.0.4

getChunkSize

public int getChunkSize()

Allows getting the current chunk size.

Returns:

the current chunk size

Since:

0.3.0.4

getMARFSourceCodeRevision

public static java.lang.String getMARFSourceCodeRevision()

Returns source code revision information.

Returns:

revision string

Since:

0.3.0.2