图像中的像素格效果是最常见的图像特效，可以隐藏或者模糊一些不想被显示出来的图像细
节，是常用的图像处理手段。
像素格效果的算法其实非常的简单，只是对图像进行块扫描，求出每个像素块的平均RGB
值，然后赋值到块中的每个像素点，最后输出处理以后的图像，而像素块的扫描有点类似
卷积的处理。具体算法步骤如下：
1. 按照从左到右，自上而下的顺序，扫描每个像素点。
2. 对扫描到的像素，计算出它属于的像素块，并且计算像素块的平均RGB值
3. 将RGB赋值给扫描到的像素点。
4. 循环上面2，3步骤，直到所有像素点都完成。
程序效果：
像素格滤镜源代码如下：
- package com.process.blur.study;
- /**
- * @author gloomy fish
- * @date 2012-05-30
- *
- */
- import java.awt.image.BufferedImage;
- public class PixellateFilter extends AbstractBufferedImageOp {
- private int size;
- public PixellateFilter() {
- size = 10; // default block size=10x10
- }
- public PixellateFilter(int size) {
- this.size = size;
- }
- @Override
- public BufferedImage filter(BufferedImage src, BufferedImage dest) {
- int width = src.getWidth();
- int height = src.getHeight();
- if ( dest == null )
- dest = createCompatibleDestImage( src, null );
- int[] inPixels = new int[width*height];
- int[] outPixels = new int[width*height];
- getRGB( src, 0, 0, width, height, inPixels );
- int index = 0;
- int offsetX = 0, offsetY = 0;
- int newX = 0, newY = 0;
- double total = size*size;
- double sumred = 0, sumgreen = 0, sumblue = 0;
- for(int row=0; row<height; row++) {
- int ta = 0, tr = 0, tg = 0, tb = 0;
- for(int col=0; col<width; col++) {
- newY = (row/size) * size;
- newX = (col/size) * size;
- offsetX = newX + size;
- offsetY = newY + size;
- for(int subRow =newY; subRow < offsetY; subRow++) {
- for(int subCol =newX; subCol < offsetX; subCol++) {
- if(subRow <0 || subRow >= height) {
- continue;
- }
- if(subCol < 0 || subCol >=width) {
- continue;
- }
- index = subRow * width + subCol;
- ta = (inPixels[index] >> 24) & 0xff;
- sumred += (inPixels[index] >> 16) & 0xff;
- sumgreen += (inPixels[index] >> 8) & 0xff;
- sumblue += inPixels[index] & 0xff;
- }
- }
- index = row * width + col;
- tr = (int)(sumred/total);
- tg = (int)(sumgreen/total);
- tb = (int)(sumblue/total);
- outPixels[index] = (ta << 24) | (tr << 16) | (tg << 8) | tb;
- sumred = sumgreen = sumblue = 0; // reset them...
- }
- }
- setRGB( dest, 0, 0, width, height, outPixels );
- return dest;
- }
- }
