/*
* $RCSfile: ClampDescriptor.java,v $
*
* Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
*
* Use is subject to license terms.
*
* $Revision: 1.1 $
* $Date: 2005/02/11 04:57:31 $
* $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.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 "Clamp" operation.
*
* <p> The Clamp operation takes one rendered or renderable source
* image, and sets all the pixels whose value is below a "low" value
* to that low value and all the pixels whose value is above a "high"
* value to that high value. The pixels whose value is between the
* "low" value and the "high" value are left unchanged.
*
* <p> A different set of "low" and "high" values may be applied to each
* band of the source image, or the same set of "low" and "high" values
* may be applied to all bands of the source. If the number of "low" and
* "high" values supplied is less than the number of bands of the source,
* then the values from entry 0 are applied to all the bands. Each "low"
* value must be less than or equal to its corresponding "high" value.
*
* <p> The destination pixel values are defined by the pseudocode:
* <pre>
* lowVal = (low.length < dstNumBands) ?
* low[0] : low[b];
* highVal = (high.length < dstNumBands) ?
* high[0] : high[b];
*
* if (src[x][y][b] < lowVal) {
* dst[x][y][b] = lowVal;
* } else if (src[x][y][b] > highVal) {
* dst[x][y][b] = highVal;
* } else {
* dst[x][y][b] = src[x][y][b];
* }
* </pre>
*
* <p><table border=1>
* <caption>Resource List</caption>
* <tr><th>Name</th> <th>Value</th></tr>
* <tr><td>GlobalName</td> <td>Clamp</td></tr>
* <tr><td>LocalName</td> <td>Clamp</td></tr>
* <tr><td>Vendor</td> <td>com.lightcrafts.media.jai</td></tr>
* <tr><td>Description</td> <td>Clamps the pixel values of an image
* to a specified range.</td></tr>
* <tr><td>DocURL</td> <td>http://java.sun.com/products/java-media/jai/forDevelopers/jai-apidocs/javax/media/jai/operator/ClampDescriptor.html</td></tr>
* <tr><td>Version</td> <td>1.0</td></tr>
* <tr><td>arg0Desc</td> <td>The lower boundary for each band.</td></tr>
* <tr><td>arg1Desc</td> <td>The upper boundary for each band.</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>low</td> <td>double[]</td>
* <td>{0.0}</td>
* <tr><td>high</td> <td>double[]</td>
* <td>{255.0}</td>
* </table></p>
*
* @see com.lightcrafts.mediax.jai.OperationDescriptor
*/
public class ClampDescriptor extends OperationDescriptorImpl {
/**
* The resource strings that provide the general documentation
* and specify the parameter list for this operation.
*/
private static final String[][] resources = {
{"GlobalName", "Clamp"},
{"LocalName", "Clamp"},
{"Vendor", "com.lightcrafts.media.jai"},
{"Description", JaiI18N.getString("ClampDescriptor0")},
{"DocURL", "http://java.sun.com/products/java-media/jai/forDevelopers/jai-apidocs/javax/media/jai/operator/ClampDescriptor.html"},
{"Version", JaiI18N.getString("DescriptorVersion")},
{"arg0Desc", JaiI18N.getString("ClampDescriptor1")},
{"arg1Desc", JaiI18N.getString("ClampDescriptor2")}
};
/** The parameter class list for this operation. */
private static final Class[] paramClasses = {
double[].class, double[].class
};
/** The parameter name list for this operation. */
private static final String[] paramNames = {
"low", "high"
};
/** The parameter default value list for this operation. */
private static final Object[] paramDefaults = {
new double[] {0.0}, new double[] {255.0}
};
/** Constructor. */
public ClampDescriptor() {
super(resources, 1, paramClasses, paramNames, paramDefaults);
}
/** Returns <code>true</code> since renderable operation is supported. */
public boolean isRenderableSupported() {
return true;
}
/**
* Validates the input parameters.
*
* <p> In addition to the standard checks performed by the
* superclass method, this method checks that "low" and "high"
* have length at least 1 and that each "low" value is less than
* or equal to the corresponding "high" value.
*/
protected boolean validateParameters(ParameterBlock args,
StringBuffer msg) {
if (!super.validateParameters(args, msg)) {
return false;
}
double[] low = (double[])args.getObjectParameter(0);
double[] high = (double[])args.getObjectParameter(1);
if (low.length < 1 || high.length < 1) {
msg.append(getName() + " " +
JaiI18N.getString("ClampDescriptor3"));
return false;
}
int length = Math.min(low.length, high.length);
for (int i = 0; i < length; i++) {
if (low[i] > high[i]) {
msg.append(getName() + " " +
JaiI18N.getString("ClampDescriptor4"));
return false;
}
}
return true;
}
/**
* Clamps the pixel values of an image to a specified range.
*
* <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 low The lower boundary for each band.
* May be <code>null</code>.
* @param high The upper boundary for each band.
* 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,
double[] low,
double[] high,
RenderingHints hints) {
ParameterBlockJAI pb =
new ParameterBlockJAI("Clamp",
RenderedRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
pb.setParameter("low", low);
pb.setParameter("high", high);
return JAI.create("Clamp", pb, hints);
}
/**
* Clamps the pixel values of an image to a specified range.
*
* <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 low The lower boundary for each band.
* May be <code>null</code>.
* @param high The upper boundary for each band.
* 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,
double[] low,
double[] high,
RenderingHints hints) {
ParameterBlockJAI pb =
new ParameterBlockJAI("Clamp",
RenderableRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
pb.setParameter("low", low);
pb.setParameter("high", high);
return JAI.createRenderable("Clamp", pb, hints);
}
}