找了好久Atkinson的Java实现，始终没找到现成的，只有一个pde的参考：

https://github.com/danielepiccone/dithering_algorithms/blob/master/atkinson_color/atkinson_color.pde

用Java重新写了一下，核心代码如：

public class BMPConverter {public static byte[][] atkinsonDither(RGBTriple[][] image, RGBTriple[] palette) {int s = 1;byte[][] result = new byte[image.length][image[0].length];// Scan imagefor (int x = s; x < image.length-2*s; x+=s) {for (int y = 0; y < image[x].length-2*s; y+=s) {// Calculate pixelRGBTriple oldpixel = image[x][y];byte index = findNearestColor(oldpixel, palette);RGBTriple newpixel = palette[index];RGBTriple quant_error = new RGBTriple(oldpixel.getRed() - newpixel.getRed(), oldpixel.getGreen() - newpixel.getGreen(), oldpixel.getBlue() - newpixel.getBlue());result[x][y] = index;// Atkinson algorithm http://verlagmartinkoch.at/software/dither/index.htmlRGBTriple s1 = image[x+s][y];image[x+s][y] = adjustRGB(s1, quant_error);RGBTriple s2 = image[x-s][y+s];image[x-s][y+s] = adjustRGB(s2, quant_error);RGBTriple s3 = image[x][y+s];image[x][y+s] = adjustRGB(s3, quant_error);RGBTriple s4 = image[x+s][y+s];image[x+s][y+s] = adjustRGB(s4, quant_error);RGBTriple s5 = image[x+2*s][y];image[x+2*s][y] = adjustRGB(s5, quant_error);RGBTriple s6 = image[x][y+2*s];image[x][y+2*s] = adjustRGB(s6, quant_error);}}return result;}private static RGBTriple adjustRGB(RGBTriple originalRGB, RGBTriple error) {return new RGBTriple((new Double(originalRGB.getRed() +  1.0/8 * error.getRed())).intValue(),(new Double(originalRGB.getGreen() + 1.0/8 * error.getGreen())).intValue(),(new Double(originalRGB.getBlue() + 1.0/8 * error.getBlue()).intValue()));}private static byte findNearestColor(RGBTriple color, RGBTriple[] palette) {int minDistanceSquared = 255 * 255 + 255 * 255 + 255 * 255 + 1;byte bestIndex = 0;for (byte i = 0; i < palette.length; i++) {int Rdiff = (color.channels[0] & 0xff) - (palette[i].channels[0] & 0xff);int Gdiff = (color.channels[1] & 0xff) - (palette[i].channels[1] & 0xff);int Bdiff = (color.channels[2] & 0xff) - (palette[i].channels[2] & 0xff);int distanceSquared = Rdiff * Rdiff + Gdiff * Gdiff + Bdiff * Bdiff;if (distanceSquared < minDistanceSquared) {minDistanceSquared = distanceSquared;bestIndex = i;}}return bestIndex;}}public class RGBTriple {public final byte[] channels;public RGBTriple() {channels = new byte[3];}public RGBTriple(int R, int G, int B) {channels = new byte[]{(byte) R, (byte) G, (byte) B};}public byte getRed() {return channels[0];}public byte getGreen() {return channels[1];}public byte getBlue() {return channels[2];}
}

显示的效果如：