/*
* $RCSfile: MatchCDFDescriptor.java,v $
*
* Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
*
* Use is subject to license terms.
*
* $Revision: 1.1 $
* $Date: 2005/02/11 04:57:38 $
* $State: Exp $
*/
package com.lightcrafts.mediax.jai.operator;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.image.RenderedImage;
import java.awt.image.renderable.ParameterBlock;
import java.awt.image.renderable.RenderableImage;
import com.lightcrafts.mediax.jai.Histogram;
import com.lightcrafts.mediax.jai.JAI;
import com.lightcrafts.mediax.jai.OperationDescriptorImpl;
import com.lightcrafts.mediax.jai.ParameterBlockJAI;
import com.lightcrafts.mediax.jai.RenderableOp;
import com.lightcrafts.mediax.jai.RenderedOp;
import com.lightcrafts.mediax.jai.registry.RenderableRegistryMode;
import com.lightcrafts.mediax.jai.registry.RenderedRegistryMode;
/**
* An <code>OperationDescriptor</code> describing the "MatchCDF" operation.
*
* <p> The "MatchCDF" operation performs a piecewise linear mapping of the
* pixel values of an image such that the Cumulative Distribution Function
* (CDF) of the destination image matches as closely as possible a specified
* Cumulative Distribution Function. The desired CDF is described by an
* array of the form <pre>float CDF[numBands][numBins[b]]</pre> where
* <pre>numBins[b]</pre> denotes the number of bins in the histogram of the
* source image for band <i>b</i>. Each element in the array
* <pre>CDF[b]</pre> must be non-negative, the array must represent a non-
* decreasing sequence, and the last element of the array must be 1.0F.
* The source image must have a <code>Histogram</code> object available via
* its <code>getProperty()</code> method.
*
* <p><table border=1>
* <caption>Resource List</caption>
* <tr><th>Name</th> <th>Value</th></tr>
* <tr><td>GlobalName</td> <td>MatchCDF</td></tr>
* <tr><td>LocalName</td> <td>MatchCDF</td></tr>
* <tr><td>Vendor</td> <td>com.lightcrafts.media.jai</td></tr>
* <tr><td>Description</td> <td>Matches pixel values to a supplied CDF.</td></tr>
* <tr><td>DocURL</td> <td>http://java.sun.com/products/java-media/jai/forDevelopers/jai-apidocs/javax/media/jai/operator/MatchCDFDescriptor.html</td></tr>
* <tr><td>Version</td> <td>1.0</td></tr>
* <tr><td>arg0Desc</td> <td>The desired Cumulative Distribution Function.</td></tr>
* </table></p>
*
* <p><table border=1>
* <caption>Parameter List</caption>
* <tr><th>Name</th> <th>Class Type</th>
* <th>Default Value</th></tr>
* <tr><td>CDF</td> <td>float[][]</td>
* <td>CDF for histogram equalization</td>
* </table></p>
*
* @see java.awt.image.DataBuffer
* @see com.lightcrafts.mediax.jai.ImageLayout
* @see com.lightcrafts.mediax.jai.OperationDescriptor
*/
public class MatchCDFDescriptor extends OperationDescriptorImpl {
/**
* The resource strings that provide the general documentation
* and specify the parameter list for this operation.
*/
private static final String[][] resources = {
{"GlobalName", "MatchCDF"},
{"LocalName", "MatchCDF"},
{"Vendor", "com.lightcrafts.media.jai"},
{"Description", JaiI18N.getString("MatchCDFDescriptor0")},
{"DocURL", "http://java.sun.com/products/java-media/jai/forDevelopers/jai-apidocs/javax/media/jai/operator/MatchCDFDescriptor.html"},
{"Version", JaiI18N.getString("DescriptorVersion")},
{"arg0Desc", "The desired Cumulative Distribution Function."},
};
/** The parameter class list for this operation. */
private static final Class[] paramClasses = {
float[][].class
};
/** The parameter name list for this operation. */
private static final String[] paramNames = {
"CDF"
};
/** The parameter default value list for this operation. */
private static final Object[] paramDefaults = {
null
};
private static final String[] supportedModes = {
"rendered",
"renderable"
};
/** Constructor. */
public MatchCDFDescriptor() {
super(resources, supportedModes, 1,
paramNames, paramClasses, paramDefaults, null);
}
/**
* Validates the input sources and parameter.
*
* <p> In addition to the standard checks performed by the
* superclass method, this method checks that the source image
* contains a "histogram" property and that the "CDF" array
* is appropriate for it.
*/
public boolean validateArguments(String modeName,
ParameterBlock args,
StringBuffer msg) {
if (!super.validateArguments(modeName, args, msg)) {
return false;
}
if (!modeName.equalsIgnoreCase("rendered"))
return true;
// Get the source and the CDF array.
RenderedImage src = args.getRenderedSource(0);
float[][] CDF = (float[][])args.getObjectParameter(0);
// Ensure that the Histogram is available and that the CDF array
// is appropriate for it.
Object prop = src.getProperty("histogram");
if(prop == null || prop.equals(Image.UndefinedProperty)) {
// Property is null or undefined.
msg.append(getName() + " " +
JaiI18N.getString("MatchCDFDescriptor1"));
return false;
} else if(!(prop instanceof Histogram)) {
// Property is not a Histogram.
msg.append(getName() + " " +
JaiI18N.getString("MatchCDFDescriptor2"));
return false;
} else {
Histogram hist = (Histogram)prop;
int numBands = hist.getNumBands();
if (CDF == null) {
int[] numBins = hist.getNumBins();
CDF = new float[numBands][];
for (int b = 0; b < numBands; b++) {
CDF[b] = new float[numBins[b]];
for (int i = 0; i < numBins[b]; i++)
CDF[b][i] = (i + 1)/numBins[b];
}
}
if(CDF.length != numBands) {
// CDF length does not match Histogram.
msg.append(getName() + " " +
JaiI18N.getString("MatchCDFDescriptor3"));
return false;
}
for(int b = 0; b < numBands; b++) {
if(CDF[b].length != hist.getNumBins(b)) {
// Check that CDF length for this band matches Histogram.
msg.append(getName() + " " +
JaiI18N.getString("MatchCDFDescriptor4"));
return false;
}
}
for(int b = 0; b < numBands; b++) {
float[] CDFband = CDF[b];
int length = CDFband.length;
if(CDFband[length-1] != 1.0) {
// Last CDF array element value is not 1.0.
msg.append(getName() + " " +
JaiI18N.getString("MatchCDFDescriptor7"));
return false;
}
for(int i = 0; i < length; i++) {
if(CDFband[i] < 0.0F) {
// Negative CDF value.
msg.append(getName() + " " +
JaiI18N.getString("MatchCDFDescriptor5"));
return false;
} else if(i != 0) {
if(CDFband[i] < CDFband[i-1]) {
// Decreasing sequence.
msg.append(getName() + " " +
JaiI18N.getString("MatchCDFDescriptor6"));
return false;
}
}
}
}
return true;
}
}
/**
* Matches pixel values to a supplied CDF.
*
* <p>Creates a <code>ParameterBlockJAI</code> from all
* supplied arguments except <code>hints</code> and invokes
* {@link JAI#create(String,ParameterBlock,RenderingHints)}.
*
* @see JAI
* @see ParameterBlockJAI
* @see RenderedOp
*
* @param source0 <code>RenderedImage</code> source 0.
* @param CDF The desired Cumulative Distribution Function.
* May be <code>null</code>.
* @param hints The <code>RenderingHints</code> to use.
* May be <code>null</code>.
* @return The <code>RenderedOp</code> destination.
* @throws IllegalArgumentException if <code>source0</code> is <code>null</code>.
*/
public static RenderedOp create(RenderedImage source0,
float[][] CDF,
RenderingHints hints) {
ParameterBlockJAI pb =
new ParameterBlockJAI("MatchCDF",
RenderedRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
pb.setParameter("CDF", CDF);
return JAI.create("MatchCDF", pb, hints);
}
/**
* Matches pixel values to a supplied CDF.
*
* <p>Creates a <code>ParameterBlockJAI</code> from all
* supplied arguments except <code>hints</code> and invokes
* {@link JAI#createRenderable(String,ParameterBlock,RenderingHints)}.
*
* @see JAI
* @see ParameterBlockJAI
* @see RenderableOp
*
* @param source0 <code>RenderableImage</code> source 0.
* @param CDF The desired Cumulative Distribution Function.
* May be <code>null</code>.
* @param hints The <code>RenderingHints</code> to use.
* May be <code>null</code>.
* @return The <code>RenderableOp</code> destination.
* @throws IllegalArgumentException if <code>source0</code> is <code>null</code>.
*/
public static RenderableOp createRenderable(RenderableImage source0,
float[][] CDF,
RenderingHints hints) {
ParameterBlockJAI pb =
new ParameterBlockJAI("MatchCDF",
RenderableRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
pb.setParameter("CDF", CDF);
return JAI.createRenderable("MatchCDF", pb, hints);
}
}