/*
* $RCSfile: MedianFilterDescriptor.java,v $
*
* Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
*
* Use is subject to license terms.
*
* $Revision: 1.1 $
* $Date: 2005/02/11 04:57:39 $
* $State: Exp $
*/
package com.lightcrafts.mediax.jai.operator;
import com.lightcrafts.media.jai.util.AreaOpPropertyGenerator;
import java.awt.RenderingHints;
import java.awt.image.RenderedImage;
import java.awt.image.renderable.ParameterBlock;
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.RenderedOp;
import com.lightcrafts.mediax.jai.operator.MedianFilterShape;
import com.lightcrafts.mediax.jai.registry.RenderedRegistryMode;
/**
* An <code>OperationDescriptor</code> describing the "MedianFilter" operation.
*
* <p> The "MedianFilter" operation is a non-linear filter which is
* useful for removing isolated lines or pixels while preserving the
* overall appearance of an image. The filter is implemented by moving
* a mask over the image. For each position of the mask, the
* center pixel is replaced by the median of the pixel values covered
* by the mask.
*
* <p> There are several shapes possible for the mask. The
* MedianFilter operation supports three shapes, as follows:
*
* <p> Square Mask:
* <pre>
* x x x
* x x x
* x x x
* </pre>
*
* <p> Plus Mask:
* <pre>
* x
* x x x
* x
* </pre>
*
* <p> X Mask:
* <pre>
* x x
* x
* x x
* </pre>
*
* <p> The Median operation may also be used to compute the "separable
* median" of a 3x3 or 5x5 region of pixels. The separable median is
* defined as the median of the medians of each row. For example, if
* the pixel values in a 3x3 window are equal to:
*
* <pre>
* [ 1 2 3 ]
* [ 5 6 7 ]
* [ 4 8 9 ]
* </pre>
*
* then the overall (non-separable) median value is 5, while the
* separable median is equal to the median of the three row medians:
* median(1, 2, 3) = 2, median(5, 6, 7) = 6, and median(4, 8, 9) = 8,
* yielding an overall median of 6. The separable median may be
* obtained by specifying a mask of type MEDIAN_MASK_SQUARE_SEPARABLE.
*
* 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 align=center border=1>
* <caption>Resource List</caption>
* <tr><th>Name</th> <th>Value</th></tr>
* <tr><td>GlobalName</td> <td>MedianFilter</td></tr>
* <tr><td>LocallName</td> <td>MedianFilter</td></tr>
* <tr><td>Vendor</td> <td>com.lightcrafts.media.jai</td></tr>
* <tr><td>Description</td> <td>Performs median filtering on an image.</td></tr>
* <tr><td>DocURL</td> <td>http://java.sun.com/products/java-media/jai/forDevelopers/jaiapi/com.lightcrafts.mediax.jai.operator.MedianFilterDescriptor.html</td></tr>
* <tr><td>Version</td> <td>1.0</td></tr>
* <tr><td>arg0Desc</td> <td>The shape of the mask to be used for Median Filtering.</td></tr>
* <tr><td>arg1Desc</td> <td>The size (width/height) of the mask to be used in Median Filtering.</td></tr>
* </table></p>
*
* <p><table align=center border=1>
* <caption>Parameter List</caption>
* <tr><th>Name</th> <th>Class Type</th>
* <th>Default Value</th></tr>
* <tr><td>maskShape</td> <td>com.lightcrafts.mediax.jai.operator.MedianFilterShape</td>
* <td>MEDIAN_MASK_SQUARE</td>
* <tr><td>maskSize</td> <td>java.lang.Integer</td>
* <td>3</td>
* </table></p>
*
* @see com.lightcrafts.mediax.jai.OperationDescriptor
* @see MedianFilterShape
*/
public class MedianFilterDescriptor extends OperationDescriptorImpl {
/**
* Default 3x3 Windows
*/
/** Square shaped mask. */
public static final MedianFilterShape MEDIAN_MASK_SQUARE =
new MedianFilterShape("MEDIAN_MASK_SQUARE", 1);
/** Plus shaped mask. */
public static final MedianFilterShape MEDIAN_MASK_PLUS =
new MedianFilterShape("MEDIAN_MASK_PLUS", 2);
/** X shaped mask. */
public static final MedianFilterShape MEDIAN_MASK_X =
new MedianFilterShape("MEDIAN_MASK_X", 3);
/** Separable square mask. */
public static final MedianFilterShape MEDIAN_MASK_SQUARE_SEPARABLE =
new MedianFilterShape("MEDIAN_MASK_SQUARE_SEPARABLE", 4);
/**
* The resource strings that provide the general documentation
* and specify the parameter list for this operation.
*/
private static final String[][] resources = {
{"GlobalName", "MedianFilter"},
{"LocalName", "MedianFilter"},
{"Vendor", "com.lightcrafts.media.jai"},
{"Description", JaiI18N.getString("MedianFilterDescriptor0")},
{"DocURL", "http://java.sun.com/products/java-media/jai/forDevelopers/jaiapi/com.lightcrafts.mediax.jai.operator.MedianFilterDescriptor.html"},
{"Version", JaiI18N.getString("DescriptorVersion2")},
{"arg0Desc", JaiI18N.getString("MedianFilterDescriptor1")},
{"arg1Desc", JaiI18N.getString("MedianFilterDescriptor2")}
};
/** The parameter class list for this operation. */
private static final Class[] paramClasses = {
MedianFilterShape.class, java.lang.Integer.class
};
/** The parameter name list for this operation. */
private static final String[] paramNames = {
"maskShape","maskSize"
};
/** The parameter default value list for this operation. */
private static final Object[] paramDefaults = {
MEDIAN_MASK_SQUARE, new Integer(3)
};
/** Constructor for the MedianFilterDescriptor. */
public MedianFilterDescriptor() {
super(resources, 1, paramClasses, paramNames, paramDefaults);
}
/**
* Returns the minimum legal value of a specified numeric parameter
* for this operation.
*/
public Number getParamMinValue(int index) {
if (index == 0) {
return null;
} else if (index == 1){
return new Integer(1);
} else {
throw new ArrayIndexOutOfBoundsException();
}
}
/**
* Returns the maximum legal value of a specified numeric parameter
* for this operation.
*/
public Number getParamMaxValue(int index) {
if (index == 0) {
return null;
} else if (index == 1){
return new Integer(Integer.MAX_VALUE);
} else {
throw new ArrayIndexOutOfBoundsException();
}
}
/**
* Returns an array of <code>PropertyGenerators</code> implementing
* property inheritance for the "MedianFilter" operation.
*
* @return An array of property generators.
*/
public PropertyGenerator[] getPropertyGenerators() {
PropertyGenerator[] pg = new PropertyGenerator[1];
pg[0] = new AreaOpPropertyGenerator();
return pg;
}
/**
* Performs median filtering on 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 maskShape The mask shape to be used for Median Filtering.
* May be <code>null</code>.
* @param maskSize The mask size to be used for Median Filtering.
* 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,
MedianFilterShape maskShape,
Integer maskSize,
RenderingHints hints) {
ParameterBlockJAI pb =
new ParameterBlockJAI("MedianFilter",
RenderedRegistryMode.MODE_NAME);
pb.setSource("source0", source0);
pb.setParameter("maskShape", maskShape);
pb.setParameter("maskSize", maskSize);
return JAI.create("MedianFilter", pb, hints);
}
}