org.openimaj.audio.features.JAudioFeatureExtractor Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of audio-processing Show documentation
Show all versions of audio-processing Show documentation
Implementations of various audio processors (e.g. multichannel conversion, volume change, ...).
/**
* Copyright (c) 2011, The University of Southampton and the individual contributors.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of the University of Southampton nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
*
*/
package org.openimaj.audio.features;
import org.openimaj.audio.AudioStream;
import org.openimaj.audio.SampleChunk;
import org.openimaj.audio.processor.AudioProcessor;
import org.openimaj.audio.samples.SampleBuffer;
import org.openimaj.feature.DoubleFV;
import org.openimaj.feature.FeatureExtractor;
import org.openimaj.util.array.ArrayUtils;
/**
* This class provides an OpenIMAJ wrapper for the JAudio library of feature extractors.
* It provides the marshalling of data from the OpenIMAJ audio streams into
* the data structures necessary for the jAudio FeatureExtractor interface.
*
* @author David Dupplaw ([email protected])
* @created 23 May 2013
* @version $Author$, $Revision$, $Date$
*/
public abstract class JAudioFeatureExtractor extends AudioProcessor
implements FeatureExtractor
{
/** The jaudio feature extractor */
protected jAudioFeatureExtractor.AudioFeatures.FeatureExtractor featureExtractor;
/** The feature that was last calculated */
private double[][] lastCalculatedFeature;
/**
* Default constructor for ad-hoc processing.
*/
public JAudioFeatureExtractor()
{
}
/**
* Chainable constructor
* @param as The audio stream to chain to.
*/
public JAudioFeatureExtractor( final AudioStream as )
{
super( as );
}
/**
* Process the given sample buffer.
* @param sb The sample buffer
* @return The sample buffer
*/
public SampleBuffer process( final SampleBuffer sb )
{
final double[][] chanSamples = sb.asDoubleChannelArray();
this.lastCalculatedFeature = new double[chanSamples.length][];
for( int c = 0; c < sb.getFormat().getNumChannels(); c++ )
this.lastCalculatedFeature[c] = this.process( chanSamples[c], sb.getFormat().getSampleRateKHz()*1000d );
return sb;
}
/**
* Process the given sample data.
* @param samples The samples
* @param sampleRate The sample rate of the data
* @return The features
*/
public double[][] process( final double[][] samples, final double sampleRate )
{
final double[][] featureVectors = new double[samples.length][];
for( int i = 0; i < samples.length; i++ )
featureVectors[i] = this.process( samples[i], sampleRate );
return featureVectors;
}
/**
* Process the given sample array for a single channel
* @param samples The samples for a single channel
* @param sampleRate The sample rate of the data
* @return The feature for the single channel
*/
public double[] process( final double[] samples, final double sampleRate )
{
// Process the feature
try
{
final double[] f = this.featureExtractor.extractFeature( samples, sampleRate,
this.getExtraInputs( samples, sampleRate ) );
return f;
}
catch( final Exception e )
{
e.printStackTrace();
}
// If an exception occurs we return null
return null;
}
/**
* Returns the extra inputs required by a specific feature extractor
* @param samples The samples for a single channel
* @param sampleRate The sample rate of the data
* @return The extra input
*/
public abstract double[][] getExtraInputs( double[] samples, double sampleRate );
/**
* {@inheritDoc}
* @see org.openimaj.audio.processor.AudioProcessor#process(org.openimaj.audio.SampleChunk)
*/
@Override
public SampleChunk process( final SampleChunk sample ) throws Exception
{
this.process( sample.getSampleBuffer() );
return sample;
}
/**
* Calculates the feature for each channel, then flattens the channel arrays
* into a single {@link DoubleFV}.
*
* {@inheritDoc}
* @see org.openimaj.feature.FeatureExtractor#extractFeature(java.lang.Object)
*/
@Override
public DoubleFV extractFeature( final SampleChunk sc )
{
// Calculate the feature vector for this frame.
this.process( sc.getSampleBuffer() );
return new DoubleFV( ArrayUtils.reshape( this.lastCalculatedFeature ) );
}
/**
* @return the lastCalculatedFeature
*/
public double[][] getLastCalculatedFeature()
{
return this.lastCalculatedFeature;
}
/**
* @param lastCalculatedFeature the lastCalculatedFeature to set
*/
public void setLastCalculatedFeature( final double[][] lastCalculatedFeature )
{
this.lastCalculatedFeature = lastCalculatedFeature;
}
}