/*
* Copyright 2013 Carnegie Mellon University. All Rights Reserved. Use is
* subject to license terms. See the file "license.terms" for information on
* usage and redistribution of this file, and for a DISCLAIMER OF ALL
* WARRANTIES.
*/
package edu.cmu.sphinx.frontend;
import static java.lang.Double.parseDouble;
import static java.lang.Integer.parseInt;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import edu.cmu.sphinx.frontend.denoise.Denoise;
import edu.cmu.sphinx.frontend.frequencywarp.MelFrequencyFilterBank;
import edu.cmu.sphinx.frontend.frequencywarp.MelFrequencyFilterBank2;
import edu.cmu.sphinx.frontend.transform.*;
import edu.cmu.sphinx.linguist.acoustic.tiedstate.KaldiLoader;
import edu.cmu.sphinx.linguist.acoustic.tiedstate.Loader;
import edu.cmu.sphinx.util.props.*;
/**
* Cepstrum is an auto-configurable DataProcessor which is used to compute a
* specific cepstrum (for a target acoustic model) given the spectrum. The
* Cepstrum is computed using a pipeline of front end components which are
* selected, customized or ignored depending on the feat.params file which
* characterizes the target acoustic model for which this cepstrum is computed.
* A typical legacy MFCC Cepstrum will use a MelFrequencyFilterBank, followed
* by a DiscreteCosineTransform. A typical denoised MFCC Cepstrum will use a
* MelFrequencyFilterBank, followed by a Denoise component, followed by a
* DiscreteCosineTransform2, followed by a Lifter component. The
* MelFrequencyFilterBank parameters (numberFilters, minimumFrequency and
* maximumFrequency) are auto-configured based on the values found in
* feat.params.
*
* @author Horia Cucu
*/
public class AutoCepstrum extends BaseDataProcessor {
/**
* The property specifying the acoustic model for which this cepstrum will
* be configured. For this acoustic model (AM) it is mandatory to specify a
* location in the configuration file. The Cepstrum will be configured
* based on the feat.params file that will be found in the specified AM
* location.
*/
@S4Component(type = Loader.class)
public final static String PROP_LOADER = "loader";
protected Loader loader;
/**
* The filter bank which will be used for creating the cepstrum. The filter
* bank is always inserted in the pipeline and its minimum frequency,
* maximum frequency and number of filters are configured based on the
* "lowerf", "upperf" and "nfilt" values in the feat.params file of the
* target acoustic model.
*/
protected BaseDataProcessor filterBank;
/**
* The denoise component which could be used for creating the cepstrum. The
* denoise component is inserted in the pipeline only if
* "-remove_noise yes" is specified in the feat.params file of the target
* acoustic model.
*/
protected Denoise denoise;
/**
* The property specifying the DCT which will be used for creating the
* cepstrum. If "-transform legacy" is specified in the feat.params file of
* the target acoustic model or if the "-transform" parameter does not
* appear in this file at all, the legacy DCT component is inserted in the
* pipeline. If "-transform dct" is specified in the feat.params file of
* the target acoustic model, then the current DCT component is inserted in
* the pipeline.
*/
protected DiscreteCosineTransform dct;
/**
* The lifter component which could be used for creating the cepstrum. The
* lifter component is inserted in the pipeline only if
* "-lifter <lifterValue>" is specified in the feat.params file of the
* target acoustic model.
*/
protected Lifter lifter;
/**
* The list of <code>DataProcessor</code>s which were auto-configured for
* this Cepstrum component.
*/
protected List<DataProcessor> selectedDataProcessors;
public AutoCepstrum(Loader loader) throws IOException {
initLogger();
this.loader = loader;
loader.load();
initDataProcessors();
}
public AutoCepstrum() {
}
/*
* (non-Javadoc)
* @see
* edu.cmu.sphinx.util.props.Configurable#newProperties(edu.cmu.sphinx.util
* .props.PropertySheet)
*/
@Override
public void newProperties(PropertySheet ps) throws PropertyException {
super.newProperties(ps);
loader = (Loader) ps.getComponent(PROP_LOADER);
try {
loader.load();
} catch (IOException e) {
throw new PropertyException(e);
}
initDataProcessors();
}
private void initDataProcessors() {
try {
Properties featParams = loader.getProperties();
selectedDataProcessors = new ArrayList<DataProcessor>();
double lowFreq = parseDouble(featParams.getProperty("-lowerf"));
double hiFreq = parseDouble(featParams.getProperty("-upperf"));
int numFilter = parseInt(featParams.getProperty("-nfilt"));
// TODO: should not be there, but for now me must preserve
// backward compatibility with the legacy code.
if (loader instanceof KaldiLoader)
filterBank = new MelFrequencyFilterBank2(lowFreq,
hiFreq,
numFilter);
else
filterBank = new MelFrequencyFilterBank(lowFreq,
hiFreq,
numFilter);
selectedDataProcessors.add(filterBank);
if ((featParams.get("-remove_noise") == null)
|| (featParams.get("-remove_noise").equals("yes"))) {
denoise = new Denoise(Denoise.class.getField("LAMBDA_POWER")
.getAnnotation(S4Double.class)
.defaultValue(),
Denoise.class.getField("LAMBDA_A")
.getAnnotation(S4Double.class)
.defaultValue(),
Denoise.class.getField("LAMBDA_B")
.getAnnotation(S4Double.class)
.defaultValue(),
Denoise.class.getField("LAMBDA_T")
.getAnnotation(S4Double.class)
.defaultValue(),
Denoise.class.getField("MU_T")
.getAnnotation(S4Double.class)
.defaultValue(),
Denoise.class.getField("MAX_GAIN")
.getAnnotation(S4Double.class)
.defaultValue(),
Denoise.class.getField("SMOOTH_WINDOW")
.getAnnotation(S4Integer.class)
.defaultValue());
// denoise.newProperties();
denoise.setPredecessor(selectedDataProcessors
.get(selectedDataProcessors.size() - 1));
selectedDataProcessors.add(denoise);
}
if ((featParams.get("-transform") != null)
&& (featParams.get("-transform").equals("dct"))) {
dct = new DiscreteCosineTransform2(
numFilter,
DiscreteCosineTransform.class
.getField("PROP_CEPSTRUM_LENGTH")
.getAnnotation(S4Integer.class)
.defaultValue());
} else if ((featParams.get("-transform") != null)
&& (featParams.get("-transform").equals("kaldi")))
{
dct = new KaldiDiscreteCosineTransform(
numFilter,
DiscreteCosineTransform.class
.getField("PROP_CEPSTRUM_LENGTH")
.getAnnotation(S4Integer.class)
.defaultValue());
} else {
dct = new DiscreteCosineTransform(numFilter,
DiscreteCosineTransform.class
.getField("PROP_CEPSTRUM_LENGTH")
.getAnnotation(S4Integer.class)
.defaultValue());
}
dct.setPredecessor(selectedDataProcessors
.get(selectedDataProcessors.size() - 1));
selectedDataProcessors.add(dct);
if (featParams.get("-lifter") != null) {
lifter = new Lifter(Integer.parseInt((String) featParams
.get("-lifter")));
lifter.setPredecessor(selectedDataProcessors
.get(selectedDataProcessors.size() - 1));
selectedDataProcessors.add(lifter);
}
logger.info("Cepstrum component auto-configured as follows: "
+ toString());
} catch (NoSuchFieldException exc) {
throw new RuntimeException(exc);
}
}
/*
* (non-Javadoc)
* @see
* edu.cmu.sphinx.frontend.DataProcessor#initialize(edu.cmu.sphinx.frontend
* .CommonConfig)
*/
@Override
public void initialize() {
super.initialize();
for (DataProcessor dataProcessor : selectedDataProcessors)
dataProcessor.initialize();
}
/**
* Returns the processed Data output, basically calls
* <code>getData()</code> on the last processor.
*
* @return a Data object that has been processed by the cepstrum
* @throws DataProcessingException if a data processor error occurs
*/
@Override
public Data getData() throws DataProcessingException {
DataProcessor dp;
dp = selectedDataProcessors.get(selectedDataProcessors.size() - 1);
return dp.getData();
}
/**
* Sets the predecessor for this DataProcessor. The predecessor is actually
* the spectrum builder.
*
* @param predecessor the predecessor of this DataProcessor
*/
@Override
public void setPredecessor(DataProcessor predecessor) {
filterBank.setPredecessor(predecessor);
}
/**
* Returns a description of this Cepstrum component in the format:
* <cepstrum name> {<DataProcessor1>, <DataProcessor2> ...
* <DataProcessorN>}
*
* @return a description of this Cepstrum
*/
@Override
public String toString() {
StringBuilder description = new StringBuilder(super.toString())
.append(" {");
for (DataProcessor dp : selectedDataProcessors)
description.append(dp).append(", ");
description.setLength(description.length() - 2);
return description.append('}').toString();
}
}