/*
* Copyright (c) 1997, 1999, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package java.awt.image;
/**
* The <code>Kernel</code> class defines a matrix that describes how a
* specified pixel and its surrounding pixels affect the value
* computed for the pixel's position in the output image of a filtering
* operation. The X origin and Y origin indicate the kernel matrix element
* that corresponds to the pixel position for which an output value is
* being computed.
*
* @see ConvolveOp
*/
public class Kernel implements Cloneable {
private int width;
private int height;
private int xOrigin;
private int yOrigin;
private float data[];
private static native void initIDs();
static {
ColorModel.loadLibraries();
initIDs();
}
/**
* Constructs a <code>Kernel</code> object from an array of floats.
* The first <code>width</code>*<code>height</code> elements of
* the <code>data</code> array are copied.
* If the length of the <code>data</code> array is less
* than width*height, an <code>IllegalArgumentException</code> is thrown.
* The X origin is (width-1)/2 and the Y origin is (height-1)/2.
* @param width width of the kernel
* @param height height of the kernel
* @param data kernel data in row major order
* @throws IllegalArgumentException if the length of <code>data</code>
* is less than the product of <code>width</code> and
* <code>height</code>
*/
public Kernel(int width, int height, float data[]) {
this.width = width;
this.height = height;
this.xOrigin = (width-1)>>1;
this.yOrigin = (height-1)>>1;
int len = width*height;
if (data.length < len) {
throw new IllegalArgumentException("Data array too small "+
"(is "+data.length+
" and should be "+len);
}
this.data = new float[len];
System.arraycopy(data, 0, this.data, 0, len);
}
/**
* Returns the X origin of this <code>Kernel</code>.
* @return the X origin.
*/
final public int getXOrigin(){
return xOrigin;
}
/**
* Returns the Y origin of this <code>Kernel</code>.
* @return the Y origin.
*/
final public int getYOrigin() {
return yOrigin;
}
/**
* Returns the width of this <code>Kernel</code>.
* @return the width of this <code>Kernel</code>.
*/
final public int getWidth() {
return width;
}
/**
* Returns the height of this <code>Kernel</code>.
* @return the height of this <code>Kernel</code>.
*/
final public int getHeight() {
return height;
}
/**
* Returns the kernel data in row major order.
* The <code>data</code> array is returned. If <code>data</code>
* is <code>null</code>, a new array is allocated.
* @param data if non-null, contains the returned kernel data
* @return the <code>data</code> array containing the kernel data
* in row major order or, if <code>data</code> is
* <code>null</code>, a newly allocated array containing
* the kernel data in row major order
* @throws IllegalArgumentException if <code>data</code> is less
* than the size of this <code>Kernel</code>
*/
final public float[] getKernelData(float[] data) {
if (data == null) {
data = new float[this.data.length];
}
else if (data.length < this.data.length) {
throw new IllegalArgumentException("Data array too small "+
"(should be "+this.data.length+
" but is "+
data.length+" )");
}
System.arraycopy(this.data, 0, data, 0, this.data.length);
return data;
}
/**
* Clones this object.
* @return a clone of this object.
*/
public Object clone() {
try {
return super.clone();
} catch (CloneNotSupportedException e) {
// this shouldn't happen, since we are Cloneable
throw new InternalError();
}
}
}