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Provides a single jar containing all JAITools modules which you can use instead of including individual modules in your project. Note: It does not include the Jiffle scripting language or Jiffle image operator.
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/* 
 *  Copyright (c) 2009-2011, Michael Bedward. All rights reserved. 
 *   
 *  Redistribution and use in source and binary forms, with or without modification, 
 *  are permitted provided that the following conditions are met: 
 *   
 *  - Redistributions of source code must retain the above copyright notice, this  
 *    list of conditions and the following disclaimer. 
 *   
 *  - Redistributions in binary form must reproduce the above copyright notice, this 
 *    list of conditions and the following disclaimer in the documentation and/or 
 *    other materials provided with the distribution.   
 *   
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 
 *  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
 *  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
 *  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR 
 *  ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
 *  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 
 *  ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 */   

package org.jaitools.media.jai.kernel;

import javax.media.jai.KernelJAI;

import org.jaitools.numeric.CompareOp;

/**
 * Static utility methods for KernelJAI objects.
 *
 * @author Michael Bedward
 * @since 1.0
 * @version $Id$
 */
public class KernelUtil {

    /**
     * Create a copy of the input kernel with element values
     * standardized to sum to 1.0. The input kernel's
     * dimensions and location of the key element are retained
     * by the new kernel.
     *
     * @param kernel the input kernel
     * @return a new KernelJAI object
     */
    public static KernelJAI standardize(KernelJAI kernel) {
        float[] data = kernel.getKernelData();
        float sum = 0f;
        for (float f : data) {
            sum += f;
        }

        for (int i = 0; i < data.length; i++) {
            data[i] /= sum;
        }

        return new KernelJAI(
                kernel.getWidth(),
                kernel.getHeight(),
                kernel.getXOrigin(),
                kernel.getYOrigin(),
                data);
    }
    
    /**
     * Creates a new kernel by copying the one provided and setting the element
     * at {@code (x, y)} to {@code value}.
     * 
     * @param kernel the existing kernel
     * @param x element X ordinate
     * @param y element Y ordinate
     * @param newValue new element value
     * 
     * @return the new kernel
     * 
     * @throws IllegalArgumentException if {@code kernel} is {@code null} or
     *         {@code x} or {@code y} are out of bounds
     */
    public static KernelJAI setElement(KernelJAI kernel, int x, int y, float newValue) {
        if (kernel == null) {
            throw new IllegalArgumentException("kernel must not be null");
        }
        
        float data[] = kernel.getKernelData();
        final int w = kernel.getWidth();
        final int h = kernel.getHeight();
        
        if (x < 0 || x >= w) {
            throw new IllegalArgumentException("x out of bounds: " + x);
        }
        if (y < 0 || y >= w) {
            throw new IllegalArgumentException("y out of bounds: " + y);
        }
        
        int index = y * w + x;
        data[index] = newValue;
        return new KernelJAI(w, h, kernel.getXOrigin(), kernel.getYOrigin(), data);
    }

    /**
     * A utility function that returns a string representation of
     * a KernelJAI object's data.
     *
     * @param kernel the input kernel
     * @param multiLine if true, each row of kernel data is followed by a newline;
     * if false, the string contains no newlines
     *
     * @return a String
     */
    public static String kernelToString(KernelJAI kernel, boolean multiLine) {
        float[] data = kernel.getKernelData();
        int w = kernel.getWidth();
        int h = kernel.getHeight();
        StringBuilder sb = new StringBuilder();

        boolean binaryData = true;
        for (int i = 0; i < data.length && binaryData; i++) {
            if (!(CompareOp.aequal(data[i], 0) || CompareOp.aequal(data[i], 1))) {
                binaryData = false;
            }
        }

        int k = 0;
        sb.append("[");
        for (int i = 0; i < w; i++) {
            sb.append("[");
            for (int j = 0; j < h; j++, k++) {
                if (binaryData) {
                    sb.append((int) data[k]);
                } else {
                    sb.append(String.format("%.4f", data[k]));
                    if (j < w-1) sb.append(" ");
                }
            }
            sb.append("]");
            if (i < w - 1) {
                if (multiLine) {
                    sb.append("\n ");
                } else {
                    sb.append(" ");
                }
            }
        }
        sb.append("]");

        return sb.toString();
    }

}