/*
* $RCSfile: DilateDescriptor.java,v $
*
* Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
*
* Use is subject to license terms.
*
* $Revision: 1.1 $
* $Date: 2005/02/11 04:57:34 $
* $State: Exp $
*/
package javax.media.jai.operator;
import com.sun.media.jai.util.AreaOpPropertyGenerator;
import java.awt.RenderingHints;
import java.awt.image.RenderedImage;
import javax.media.jai.JAI;
import javax.media.jai.KernelJAI;
import javax.media.jai.OperationDescriptorImpl;
import javax.media.jai.ParameterBlockJAI;
import javax.media.jai.PropertyGenerator;
import javax.media.jai.RenderedOp;
import javax.media.jai.registry.RenderedRegistryMode;
/**
* An <code>OperationDescriptor</code> describing the "Dilate" operation.
*
* Dilation for gray scale images can be charaterized by "slide, add and max",
* while for binary images by "slide and set". As always, the kernel
* is expected to come with a key position.
*
* <p> Dilation, unlike convolution and most neighborhood operations,
* actually can grow the image region. But to conform with other
* image neighborhood operations, the border pixels are set to 0.
* For a 3 x 3 kernel with the key point at the center, there will
* be a pixel wide 0 stripe around the border.
*
* <p>When applied to multi-band images the dilation operator processes
* each band independently using the methodology which would be applied
* to single band images of the same data type.
*
* <p> <b> Gray scale dilation</b> is a spatial operation that computes
* each output sample by adding elements of a kernel to the samples
* surrounding a particular source sample and taking the maximum.
* A mathematical expression is:
*
* <p> For a kernel K with a key position (xKey,yKey), the dilation
* of image I at (x,y) is given by:
* <pre>
* max{ I(x-i, y-j) + K(xKey+i, yKey+j): some (i,j) restriction }
*
* where the (i,j) restriction means:
* all possible (i,j) so that both I(x-i,y-j) and K(xKey+i, yKey+j)
* are defined, that is, these indices are in bounds.
*
* </pre>
* <p>Intuitively in 2D, the kernel is like
* an umbrella and the key point is the handle. When the handle moves
* all over the image surface, the upper outbounds of all the umbrella
* positions is the dilation. Thus if you want the image to dilate in
* the upper right direction, the following kernel would do with
* the bold face key position.
*
* <p><center>
* <table border=1>
* <tr align=center><td>0</td><td>0</td><td>50</td> </tr>
* <tr align=center><td>0</td><td>50</td><td>0</td> </tr>
* <tr align=center><td><b>0</b></td><td>0</td><td>0</td> </tr>
* </table></center>
*
* <p> Note also that zero kernel have effects on the dilation!
* That is because of the "max" in the add and max process. Thus
* a 3 x 1 zero kernel with the key position at the bottom of the kernel
* dilates the image upwards.
*
* <p>
* After the kernel is rotated 180 degrees, Pseudo code for dilation operation
* is as follows. Of course, you should provide the kernel in its
* (unrotated) original form. Assuming the kernel K is of size M rows x N cols
* and the key position is (xKey, yKey).
*
* <pre>
* // gray-scale dilation:
* for every dst pixel location (x,y){
* dst[x][y] = -infinity;
* for (i = -xKey; i < M - xKey; i++){
* for (j = -yKey; j < N - yKey; j++){
* if((x+i, y+j) are in bounds of src &&
* (xKey+i, yKey+j) are in bounds of K){
* tmp = src[x + i][y + j]+ K[xKey + i][yKey + j];
* dst[x][y] = max{tmp, dst[x][y]};
* }
* }
* }
* }
* </pre>
*
* <p> The kernel cannot be bigger in any dimension than the image data.
*
* <p> <b>Binary Image Dilation</b>
* requires the kernel K to be binary, that is, have values 0 or 1
* for all kernel entries.
* Intuitively, starting from dst image being a duplicate of src,
* binary dilation slides the kernel K to place the key position
* at every non-zero point (x,y) in src image and set dst positions
* under ones of K to 1.
*
* <p> After the kernel is rotated 180 degrees, the pseudo code for
* dilation operation is as follows. (Of course, you should provide
* the kernel in its original unrotated form.)
*
* <pre>
*
* // binary dilation
* for every dst pixel location (x,y){
* dst[x][y] = src[x][y];
* for (i = -xKey; i < M - xKey; i++){
* for (j = -yKey; j < N - yKey; j++){
* if(src[x+i,y+i]==1 && Key(xKey+i, yKey+j)==1){
* dst[x][y] = 1; break;
* }
* }
* }
* }
*
* It should be noted that this operation automatically adds a
* value of <code>Boolean.TRUE</code> for the
* <code>JAI.KEY_REPLACE_INDEX_COLOR_MODEL</code> to the given
* <code>configuration</code> so that the operation is performed
* on the pixel values instead of being performed on the indices into
* the color map if the source(s) have an <code>IndexColorModel</code>.
* This addition will take place only if a value for the
* <code>JAI.KEY_REPLACE_INDEX_COLOR_MODEL</code> has not already been
* provided by the user. Note that the <code>configuration</code> Map
* is cloned before the new hint is added to it. The operation can be
* smart about the value of the <code>JAI.KEY_REPLACE_INDEX_COLOR_MODEL</code>
* <code>RenderingHints</code>, i.e. while the default value for the
* <code>JAI.KEY_REPLACE_INDEX_COLOR_MODEL</code> is
* <code>Boolean.TRUE</code>, in some cases the operator could set the
* default.
*
* <p><table border=1>
* <caption>Resource List</caption>
* <tr><th>Name</th> <th>Value</th></tr>
* <tr><td>GlobalName</td> <td>Dilate</td></tr>
* <tr><td>LocalName</td> <td>Dilate</td></tr>
* <tr><td>Vendor</td> <td>com.sun.media.jai</td></tr>
* <tr><td>Description</td> <td>Performs kernel based Dilate on
* an image.</td></tr>
* <tr><td>DocURL</td> <td>http://java.sun.com/products/java-media/jai/forD
evelopers/jai-apidocs/javax/media/jai/operator/DilateDescriptor.html</td
></tr>
* <tr><td>Version</td> <td>1.1</td></tr>
* <tr><td>arg0Desc</td> <td>The dilate kernel.</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>kernel</td> <td>javax.media.jai.KernelJAI</td>
* <td>NO_PARAMETER_DEFAULT</td>
* </table></p>
*
* </pre>
* <p> Reference: An Introduction to Nonlinear Image Processing,
* by Edward R. Bougherty and Jaakko Astola,
* Spie Optical Engineering Press, 1994.
*
* @see javax.media.jai.OperationDescriptor
* @see javax.media.jai.KernelJAI
* @see javax.media.jai.operator.ErodeDescriptor
*
* @since JAI 1.1
*/
public class DilateDescriptor extends OperationDescriptorImpl {
/**
* The resource strings that provide the general documentation and
* specify the parameter list for a Dilate operation.
*/
private static final String[][] resources = {
{"GlobalName", "Dilate"},
{"LocalName", "Dilate"},
{"Vendor", "com.sun.media.jai"},
{"Description", JaiI18N.getString("DilateDescriptor0")},
{"DocURL", "http://java.sun.com/products/java-media/jai/forDevelopers/jaiapi/<br>javax.media.jai.operator.DilateDescriptor.html"},
{"Version", JaiI18N.getString("DescriptorVersion")},
{"arg0Desc", JaiI18N.getString("DilateDescriptor1")}
};
/** The parameter names for the Dilate operation. */
private static final String[] paramNames = {
"kernel"
};
/** The parameter class types for the Dilate operation. */
private static final Class[] paramClasses = {
javax.media.jai.KernelJAI.class
};
/** The parameter default values for the Dilate operation. */
private static final Object[] paramDefaults = {
NO_PARAMETER_DEFAULT
};
/** Constructor. */
public DilateDescriptor() {
super(resources, 1, paramClasses, paramNames, paramDefaults);
}
/**
* Returns an array of <code>PropertyGenerators</code> implementing
* property inheritance for the "Dilate" operation.
*
* @return An array of property generators.
*/
public PropertyGenerator[] getPropertyGenerators() {
PropertyGenerator[] pg = new PropertyGenerator[1];
pg[0] = new AreaOpPropertyGenerator();
return pg;
}
/**
* Performs binary kernel based Dilate operation on the 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 kernel The binary convolution kernel.
* @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>.
* @throws IllegalArgumentException if <code>kernel</code> is <code>null</code>.
*/
public static RenderedOp create(RenderedImage source0,
KernelJAI kernel,
RenderingHints hints) {
ParameterBlockJAI pb =
new ParameterBlockJAI("Dilate",
RenderedRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
pb.setParameter("kernel", kernel);
return JAI.create("Dilate", pb, hints);
}
}