edu.cmu.sphinx.frontend.feature
Class S3FeatureExtractor

java.lang.Object
  extended by edu.cmu.sphinx.frontend.BaseDataProcessor
      extended by edu.cmu.sphinx.frontend.feature.S3FeatureExtractor
All Implemented Interfaces:
DataProcessor, Configurable

public class S3FeatureExtractor
extends BaseDataProcessor

Computes the delta and double delta of input cepstrum (or plp or ...). The delta is the first order derivative and the double delta (a.k.a. delta delta) is the second order derivative of the original cepstrum. They help model the speech signal dynamics. The output data is a FloatData object with a float array of size three times the original cepstrum.

The format of the outputted feature is:

12 cepstra (c[1] through c[12])
followed by delta cepstra (delta c[1] through delta c[12])
followed by c[0], delta c[0]
followed by delta delta c[0] through delta delta c[12]


Field Summary
static java.lang.String PROP_FEATURE_WINDOW
          The name of the SphinxProperty for the window of the S3FeatureExtractor.
static int PROP_FEATURE_WINDOW_DEFAULT
          The default value of PROP_FEATURE_WINDOW.
 
Constructor Summary
S3FeatureExtractor()
           
 
Method Summary
 Data getData()
          Returns the next Data object produced by this S3FeatureExtractor.
 void initialize()
          Initializes this DataProcessor.
 void newProperties(PropertySheet ps)
          This method is called when this configurable component needs to be reconfigured.
 
Methods inherited from class edu.cmu.sphinx.frontend.BaseDataProcessor
getPredecessor, getTimer, setPredecessor, toString
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Field Detail

PROP_FEATURE_WINDOW

@S4Integer(defaultValue=3)
public static final java.lang.String PROP_FEATURE_WINDOW
The name of the SphinxProperty for the window of the S3FeatureExtractor.

See Also:
Constant Field Values

PROP_FEATURE_WINDOW_DEFAULT

public static final int PROP_FEATURE_WINDOW_DEFAULT
The default value of PROP_FEATURE_WINDOW.

See Also:
Constant Field Values
Constructor Detail

S3FeatureExtractor

public S3FeatureExtractor()
Method Detail

newProperties

public void newProperties(PropertySheet ps)
                   throws PropertyException
Description copied from interface: Configurable
This method is called when this configurable component needs to be reconfigured.

Specified by:
newProperties in interface Configurable
Overrides:
newProperties in class BaseDataProcessor
Parameters:
ps - a property sheet holding the new data
Throws:
PropertyException - if there is a problem with the properties.

initialize

public void initialize()
Description copied from class: BaseDataProcessor
Initializes this DataProcessor. This is typically called after the DataProcessor has been configured.

Specified by:
initialize in interface DataProcessor
Overrides:
initialize in class BaseDataProcessor

getData

public Data getData()
             throws DataProcessingException
Returns the next Data object produced by this S3FeatureExtractor.

Specified by:
getData in interface DataProcessor
Specified by:
getData in class BaseDataProcessor
Returns:
the next available Data object, returns null if no Data is available
Throws:
DataProcessingException - if there is a data processing error