AbstractConvolveImageOp.java

/*
 * Copyright (c) 2009 Piotr Piastucki
 * 
 * This file is part of Patchca CAPTCHA library.
 * 
 *  Patchca is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *  
 *  Patchca 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 Lesser General Public License for more details.
 *  
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with Patchca. If not, see <http://www.gnu.org/licenses/>.
 */
package com.xiongyingqi.captcha.filter.library;


public abstract class AbstractConvolveImageOp extends AbstractImageOp {

    private float[][] matrix;

    protected AbstractConvolveImageOp(float[][] matrix) {
        this.matrix = matrix;
    }

    @Override
    protected void filter(int[] inPixels, int[] outPixels, int width, int height) {
        long time1 = System.currentTimeMillis();
        int matrixWidth = matrix[0].length;
        int matrixHeight = matrix.length;
        int mattrixLeft = -matrixWidth / 2;
        int matrixTop = -matrixHeight / 2;
        for (int y = 0; y < height; y++) {
            int ytop = y + matrixTop;
            int ybottom = y + matrixTop + matrixHeight;
            for (int x = 0; x < width; x++) {
                float[] sum = {0.5f, 0.5f, 0.5f, 0.5f};
                int xleft = x + mattrixLeft;
                int xright = x + mattrixLeft + matrixWidth;
                int matrixY = 0;
                for (int my = ytop; my < ybottom; my++, matrixY++) {
                    int matrixX = 0;
                    for (int mx = xleft; mx < xright; mx++, matrixX++) {
                        int pixel = getPixel(inPixels, mx, my, width, height, EDGE_ZERO);
                        float m = matrix[matrixY][matrixX];
                        sum[0] += m * ((pixel >> 24) & 0xff);
                        sum[1] += m * ((pixel >> 16) & 0xff);
                        sum[2] += m * ((pixel >> 8) & 0xff);
                        sum[3] += m * (pixel & 0xff);
                    }
                }
                outPixels[x + y * width] = (limitByte((int) sum[0]) << 24) | (limitByte((int) sum[1]) << 16) | (limitByte((int) sum[2]) << 8) | (limitByte((int) sum[3]));
            }
        }
        long time2 = System.currentTimeMillis() - time1;
        //System.out.println("AbstractConvolveImageOp " + time2);

    }


}