jAudioFeatureExtractor.AudioFeatures
Class LPC

java.lang.Object
  extended by jAudioFeatureExtractor.AudioFeatures.FeatureExtractor
      extended by jAudioFeatureExtractor.AudioFeatures.LPC

public class LPC
extends FeatureExtractor

Calculates linear predictive coeffecients of an signal. Also includes a warping factor lambda that is disabled by default. Based upon code published at www.musicdsp.org.

2005. Music-dsp source code archive [online]. [cited 17 May 2005]. Available from the World Wide Web: (http://musicdsp.org/archive.php?classid=2#137)

Author:
Daniel McEnnis

Field Summary
 
Fields inherited from class jAudioFeatureExtractor.AudioFeatures.FeatureExtractor
definition, dependencies, offsets, parent
 
Constructor Summary
LPC()
          Basic constructor for LPC that sets definition, dependencies, and offsets field.
 
Method Summary
 java.lang.Object clone()
          Provide a complete copy of this feature.
 double[] extractFeature(double[] samples, double sampling_rate, double[][] other_feature_values)
          Code taken from www.musicdsp.org.
 java.lang.String getElement(int index)
          Function permitting an unintelligent outside function (ie.
 void setElement(int index, java.lang.String value)
          Function permitting an unintelligent outside function (ie.
 void setLambda(double l)
          Provides a mechanism for editing the 'frequency warping' factor in the LPC code from musicdsp.
 void setNumDimensions(int n)
          Edits the number of LPC coeffecients to be calculated.
 
Methods inherited from class jAudioFeatureExtractor.AudioFeatures.FeatureExtractor
getDepenedencies, getDepenedencyOffsets, getFeatureDefinition, setParent, setWindow
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

LPC

public LPC()
Basic constructor for LPC that sets definition, dependencies, and offsets field.

Method Detail

extractFeature

public double[] extractFeature(double[] samples,
                               double sampling_rate,
                               double[][] other_feature_values)
                        throws java.lang.Exception
Code taken from www.musicdsp.org.

mail.mutagene.net.2005. Music dsp source archive [online] [cited May 10, 2005] Available on world wide web (http://musicdsp.org/archive.php?classid=2#137)

Specified by:
extractFeature in class FeatureExtractor
Parameters:
samples - The samples to extract the feature from.
sampling_rate - The sampling rate that the samples are encoded with.
other_feature_values - The values of other features that are needed to calculate this value. The order and offsets of these features must be the same as those returned by this class's getDependencies and getDependencyOffsets methods respectively. The first indice indicates the feature/window and the second indicates the value.
Returns:
The extracted feature value(s).
Throws:
java.lang.Exception - Throws an informative exception if the feature cannot be calculated.
See Also:
FeatureExtractor.extractFeature(double[], double, double[][])

clone

public java.lang.Object clone()
Provide a complete copy of this feature. Used to implement the prottype pattern

Specified by:
clone in class FeatureExtractor

getElement

public java.lang.String getElement(int index)
                            throws java.lang.Exception
Function permitting an unintelligent outside function (ie. EditFeatures frame) to get the default values used to populate the table's entries. The correct index values are inferred from definition.attribute value.

Overrides:
getElement in class FeatureExtractor
Parameters:
index - which of AreaMoment's attributes should be edited.
Throws:
java.lang.Exception

setElement

public void setElement(int index,
                       java.lang.String value)
                throws java.lang.Exception
Function permitting an unintelligent outside function (ie. EditFeatures frame) to set the default values used to popylate the table's entries. Like getElement, the correct index values are inferred from the definition.attributes value.

Overrides:
setElement in class FeatureExtractor
Parameters:
index - attribute to be set
value - new value of the attribute
Throws:
java.lang.Exception

setNumDimensions

public void setNumDimensions(int n)
                      throws java.lang.Exception
Edits the number of LPC coeffecients to be calculated. This is a unique feature in that the number of dimensions of the feature are changed by this function, requiring a reference back to the parent to redraw the table displaying this information.

Parameters:
n - number of coeffecients to be calculated.
Throws:
java.lang.Exception - thrown if less than 1 feature is to be calculated.

setLambda

public void setLambda(double l)
               throws java.lang.Exception
Provides a mechanism for editing the 'frequency warping' factor in the LPC code from musicdsp.

Parameters:
l - new lmbda value
Throws:
java.lang.Exception - throws if the lambda value is not a real number.