/*
* $RCSfile: LogDescriptor.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 javax.media.jai.operator;
import java.awt.RenderingHints;
import java.awt.image.RenderedImage;
import java.awt.image.renderable.RenderableImage;
import javax.media.jai.JAI;
import javax.media.jai.OperationDescriptorImpl;
import javax.media.jai.ParameterBlockJAI;
import javax.media.jai.RenderableOp;
import javax.media.jai.RenderedOp;
import javax.media.jai.registry.RenderableRegistryMode;
import javax.media.jai.registry.RenderedRegistryMode;
/**
* An <code>OperationDescriptor</code> describing the "Log" operation.
*
* <p> The "Log" operation takes the natural logarithm of the pixel
* values of an image. The operation is done on a per-pixel, per-band
* basis. For integral data types, the result will be rounded and
* clamped as needed. The pixel values of the destination image are
* defined as:
* <pre>
* dst[x][y][b] = java.lang.Math.log(src[x][y][b])
* </pre>
*
* <p> For all integral data types, the log of 0 is set to 0. For
* signed integral data types (<code>short</code> and <code>int</code>),
* the log of a negative pixel value is set to -1.
*
* <p> For all floating point data types ((<code>float</code> and
* <code>double</code>), the log of 0 is set to <code>-Infinity</code>,
* and the log of a negative pixel value is set to <code>NaN</code>.
*
* <p><table border=1>
* <caption>Resource List</caption>
* <tr><th>Name</th> <th>Value</th></tr>
* <tr><td>GlobalName</td> <td>Log</td></tr>
* <tr><td>LocalName</td> <td>Log</td></tr>
* <tr><td>Vendor</td> <td>com.sun.media.jai</td></tr>
* <tr><td>Description</td> <td>Computes the natural logarithm of the pixel values
* 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/LogDescriptor.html</td></tr>
* <tr><td>Version</td> <td>1.0</td></tr>
* </table></p>
*
* <p> No parameters are needed for the "Log" operation.
*
* @see javax.media.jai.OperationDescriptor
*/
public class LogDescriptor extends OperationDescriptorImpl {
/**
* The resource strings that provide the general documentation
* and specify the parameter list for this operation.
*/
private static final String[][] resources = {
{"GlobalName", "Log"},
{"LocalName", "Log"},
{"Vendor", "com.sun.media.jai"},
{"Description", JaiI18N.getString("LogDescriptor0")},
{"DocURL", "http://java.sun.com/products/java-media/jai/forDevelopers/jai-apidocs/javax/media/jai/operator/LogDescriptor.html"},
{"Version", JaiI18N.getString("DescriptorVersion")}
};
/** Constructor. */
public LogDescriptor() {
super(resources, 1, null, null, null);
}
/** Returns <code>true</code> since renderable operation is supported. */
public boolean isRenderableSupported() {
return true;
}
/**
* Computes the natural logarithm of the pixel values 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("Log",
RenderedRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
return JAI.create("Log", pb, hints);
}
/**
* Computes the natural logarithm of the pixel values 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("Log",
RenderableRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
return JAI.createRenderable("Log", pb, hints);
}
}