/*
* $RCSfile: PhaseDescriptor.java,v $
*
* Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
*
* Use is subject to license terms.
*
* $Revision: 1.1 $
* $Date: 2005/02/11 04:57:42 $
* $State: Exp $
*/
package com.lightcrafts.mediax.jai.operator;
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.JAI;
import com.lightcrafts.mediax.jai.OperationDescriptorImpl;
import com.lightcrafts.mediax.jai.ParameterBlockJAI;
import com.lightcrafts.mediax.jai.PropertyGenerator;
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 "Phase" operation.
*
* <p> The "Phase" operation computes the phase angle of each pixel of a
* complex image. The source image must have an even number of bands, with
* the even bands (0, 2, ...) representing the real parts and the odd bands
* (1, 3, ...) the imaginary parts of each complex pixel. The destination
* image has at most half the number of bands of the source image with each
* sample in a pixel representing the phase angle of the corresponding complex
* source sample. The angular values of the destination image are defined
* for a given sample by the pseudocode:
*
* <pre>dst[x][y][b] = Math.atan2(src[x][y][2*b+1], src[x][y][2*b])</pre>
*
* where the number of bands <i>b</i> varies from zero to one less than the
* number of bands in the destination image.
*
* <p> For integral image datatypes, the result will be rounded and
* scaled so the the "natural" arctangent range [-PI, PI) is remapped into
* the range [0, MAX_VALUE); the result for floating point image datatypes
* is the value returned by the atan2() method.
*
* <p>"Phase" defines a PropertyGenerator that sets the "COMPLEX"
* property of the image to <code>java.lang.Boolean.FALSE</code>, which may
* be retrieved by calling the <code>getProperty()</code> method with
* "COMPLEX" as the property name.
*
* <p><table border=1>
* <caption>Resource List</caption>
* <tr><th>Name</th> <th>Value</th></tr>
* <tr><td>GlobalName</td> <td>Phase</td></tr>
* <tr><td>LocalName</td> <td>Phase</td></tr>
* <tr><td>Vendor</td> <td>com.lightcrafts.media.jai</td></tr>
* <tr><td>Description</td> <td>Computes the phase angle of each pixel of
* an image.</td></tr>
* <tr><td>DocURL</td> <td>http://java.sun.com/products/java-media/jai/forDevelopers/jai-apidocs/javax/media/jai/operator/PhaseDescriptor.html</td></tr>
* <tr><td>Version</td> <td>1.0</td></tr>
* </table></p>
*
* <p> No parameters are needed for the "Phase" operation.
*
* @see com.lightcrafts.mediax.jai.OperationDescriptor
*/
public class PhaseDescriptor extends OperationDescriptorImpl {
/**
* The resource strings that provide the general documentation
* and specify the parameter list for this operation.
*/
private static final String[][] resources = {
{"GlobalName", "Phase"},
{"LocalName", "Phase"},
{"Vendor", "com.lightcrafts.media.jai"},
{"Description", JaiI18N.getString("PhaseDescriptor0")},
{"DocURL", "http://java.sun.com/products/java-media/jai/forDevelopers/jai-apidocs/javax/media/jai/operator/PhaseDescriptor.html"},
{"Version", JaiI18N.getString("DescriptorVersion")}
};
private static final String[] supportedModes = {
"rendered",
"renderable"
};
/** Constructor. */
public PhaseDescriptor() {
super(resources, supportedModes, 1, null, null, null, null);
}
/**
* Validates the input source.
*
* <p> In addition to the standard checks performed by the
* superclass method, this method checks that the source image
* has an even number of bands.
*/
protected boolean validateSources(String modeName,
ParameterBlock args,
StringBuffer msg) {
if (!super.validateSources(modeName, args, msg)) {
return false;
}
if (!modeName.equalsIgnoreCase("rendered"))
return true;
RenderedImage src = args.getRenderedSource(0);
int bands = src.getSampleModel().getNumBands();
if (bands % 2 != 0) {
msg.append(getName() + " " +
JaiI18N.getString("PhaseDescriptor1"));
return false;
}
return true;
}
/**
* Returns an array of <code>PropertyGenerators</code> implementing
* property inheritance for the "Phase" operation.
*
* @return An array of property generators.
*/
public PropertyGenerator[] getPropertyGenerators(String modeName) {
PropertyGenerator[] pg = new PropertyGenerator[1];
pg[0] = new ComplexPropertyGenerator();
return pg;
}
/**
* Computes the phase angle of each pixel of an image.
*
* <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 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,
RenderingHints hints) {
ParameterBlockJAI pb =
new ParameterBlockJAI("Phase",
RenderedRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
return JAI.create("Phase", pb, hints);
}
/**
* Computes the phase angle of each pixel of an image.
*
* <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 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,
RenderingHints hints) {
ParameterBlockJAI pb =
new ParameterBlockJAI("Phase",
RenderableRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
return JAI.createRenderable("Phase", pb, hints);
}
}