Java Image Blur blur(int[] srcPixels, int[] dstPixels, int width, int height, float[] kernel, int radius)

Description

Blurs the source pixels into the destination pixels.

License

Open Source License

Parameter

Parameter	Description
srcPixels	the source pixels
dstPixels	the destination pixels
width	the width of the source picture
height	the height of the source picture
kernel	the kernel of the blur effect
radius	the radius of the blur effect

Declaration

private static void blur(int[] srcPixels, int[] dstPixels, int width, int height, float[] kernel, int radius) 

Method Source Code

//package com.java2s;
/*//w w w. j  av a  2 s  .  c o  m
 * %W% %E%
 *
 * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

public class Main {
    /**
     * <p>Blurs the source pixels into the destination pixels. The force of the blur is specified by the radius which
     * must be greater than 0.</p> <p>The source and destination pixels arrays are expected to be in the INT_ARGB
     * format.</p> <p>After this method is executed, dstPixels contains a transposed and filtered copy of
     * srcPixels.</p>
     *
     * @param srcPixels the source pixels
     * @param dstPixels the destination pixels
     * @param width     the width of the source picture
     * @param height    the height of the source picture
     * @param kernel    the kernel of the blur effect
     * @param radius    the radius of the blur effect
     */
    private static void blur(int[] srcPixels, int[] dstPixels, int width, int height, float[] kernel, int radius) {
        float a;
        float r;
        float g;
        float b;

        int ca;
        int cr;
        int cg;
        int cb;

        for (int y = 0; y < height; y++) {
            int index = y;
            int offset = y * width;

            for (int x = 0; x < width; x++) {
                a = r = g = b = 0.0f;

                for (int i = -radius; i <= radius; i++) {
                    int subOffset = x + i;
                    if (subOffset < 0 || subOffset >= width) {
                        subOffset = (x + width) % width;
                    }

                    int pixel = srcPixels[offset + subOffset];
                    float blurFactor = kernel[radius + i];

                    a += blurFactor * ((pixel >> 24) & 0xFF);
                    r += blurFactor * ((pixel >> 16) & 0xFF);
                    g += blurFactor * ((pixel >> 8) & 0xFF);
                    b += blurFactor * ((pixel) & 0xFF);
                }

                ca = (int) (a + 0.5f);
                cr = (int) (r + 0.5f);
                cg = (int) (g + 0.5f);
                cb = (int) (b + 0.5f);

                dstPixels[index] = ((ca > 255 ? 255 : ca) << 24) | ((cr > 255 ? 255 : cr) << 16)
                        | ((cg > 255 ? 255 : cg) << 8) | (cb > 255 ? 255 : cb);
                index += height;
            }
        }
    }

    /**
     * <p>Blurs the source pixels into the destination pixels. The force of the blur is specified by the radius which
     * must be greater than 0.</p> <p>The source and destination pixels arrays are expected to be in the BYTE_GREY
     * format.</p> <p>After this method is executed, dstPixels contains a transposed and filtered copy of
     * srcPixels.</p>
     *
     * @param srcPixels the source pixels
     * @param dstPixels the destination pixels
     * @param width     the width of the source picture
     * @param height    the height of the source picture
     * @param kernel    the kernel of the blur effect
     * @param radius    the radius of the blur effect
     */
    static void blur(byte[] srcPixels, byte[] dstPixels, int width, int height, float[] kernel, int radius) {
        float p;
        int cp;
        for (int y = 0; y < height; y++) {
            int index = y;
            int offset = y * width;
            for (int x = 0; x < width; x++) {
                p = 0.0f;
                for (int i = -radius; i <= radius; i++) {
                    int subOffset = x + i;
                    //                    if (subOffset < 0) subOffset = 0;
                    //                    if (subOffset >= width) subOffset = width-1;
                    if (subOffset < 0 || subOffset >= width) {
                        subOffset = (x + width) % width;
                    }
                    int pixel = srcPixels[offset + subOffset] & 0xFF;
                    float blurFactor = kernel[radius + i];
                    p += blurFactor * pixel;
                }
                cp = (int) (p + 0.5f);
                dstPixels[index] = (byte) (cp > 255 ? 255 : cp);
                index += height;
            }
        }
    }
}

Related

1. blur(BufferedImage image, Kernel kernel)
2. blurImage(BufferedImage image, float blurValue)
3. blurImage(BufferedImage img, BufferedImage dest)
4. blurPass(int[] srcPixels, int[] dstPixels, int width, int height, int radius)
5. blurredImage(BufferedImage source, double radius)