blur a Bitmap Image by radius - Android Graphics

Android examples for Graphics:Bitmap Blur

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Description

blur a Bitmap Image by radius

Demo Code


//package com.book2s;
import android.graphics.Bitmap;

public class Main {
    public static Bitmap blur(Bitmap bitmap, int radius) {
        int iterations = 1;
        //      int radius = 8;
        int width = bitmap.getWidth();
        int height = bitmap.getHeight();
        int[] inPixels = new int[width * height];
        int[] outPixels = new int[width * height];
        Bitmap blured = Bitmap.createBitmap(width, height,
                Bitmap.Config.ARGB_8888);
        bitmap.getPixels(inPixels, 0, width, 0, 0, width, height);
        for (int i = 0; i < iterations; i++) {
            blur(inPixels, outPixels, width, height, radius);
            blur(outPixels, inPixels, height, width, radius);
        }/*from  w  ww  .  ja v  a2s .com*/
        blured.setPixels(inPixels, 0, width, 0, 0, width, height);
        return blured;
    }

    private static void blur(int[] in, int[] out, int width, int height,
            int radius) {
        int widthMinus1 = width - 1;
        int tableSize = 2 * radius + 1;
        int divide[] = new int[256 * tableSize];

        for (int index = 0; index < 256 * tableSize; index++) {
            divide[index] = index / tableSize;
        }

        int inIndex = 0;

        for (int y = 0; y < height; y++) {
            int outIndex = y;
            int ta = 0, tr = 0, tg = 0, tb = 0;

            for (int i = -radius; i <= radius; i++) {
                int rgb = in[inIndex + clamp(i, 0, width - 1)];
                ta += (rgb >> 24) & 0xff;
                tr += (rgb >> 16) & 0xff;
                tg += (rgb >> 8) & 0xff;
                tb += rgb & 0xff;
            }

            for (int x = 0; x < width; x++) {
                out[outIndex] = (divide[ta] << 24) | (divide[tr] << 16)
                        | (divide[tg] << 8) | divide[tb];

                int i1 = x + radius + 1;
                if (i1 > widthMinus1)
                    i1 = widthMinus1;
                int i2 = x - radius;
                if (i2 < 0)
                    i2 = 0;
                int rgb1 = in[inIndex + i1];
                int rgb2 = in[inIndex + i2];

                ta += ((rgb1 >> 24) & 0xff) - ((rgb2 >> 24) & 0xff);
                tr += ((rgb1 & 0xff0000) - (rgb2 & 0xff0000)) >> 16;
                tg += ((rgb1 & 0xff00) - (rgb2 & 0xff00)) >> 8;
                tb += (rgb1 & 0xff) - (rgb2 & 0xff);
                outIndex += height;
            }
            inIndex += width;
        }
    }

    private static int clamp(int x, int a, int b) {
        return (x < a) ? a : (x > b) ? b : x;
    }
}

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