/*** 光晕效果

*@parambmp

*@paramx 光晕中心点在bmp中的x坐标

*@paramy 光晕中心点在bmp中的y坐标

*@paramr 光晕的半径

*@return

*/

public Bitmap halo(Bitmap bmp, int x, int y, floatr)

{long start =System.currentTimeMillis();//高斯矩阵

int[] gauss = new int[] { 1, 2, 1, 2, 4, 2, 1, 2, 1};int width =bmp.getWidth();int height =bmp.getHeight();

Bitmap bitmap=Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565);int pixR = 0;int pixG = 0;int pixB = 0;int pixColor = 0;int newR = 0;int newG = 0;int newB = 0;int delta = 18; //值越小图片会越亮，越大则越暗

int idx = 0;int[] pixels = new int[width *height];

bmp.getPixels(pixels,0, width, 0, 0, width, height);for (int i = 1, length = height - 1; i < length; i++)

{for (int k = 1, len = width - 1; k < len; k++)

{

idx= 0;int distance = (int) (Math.pow(k - x, 2) + Math.pow(i - y, 2));//不是中心区域的点做模糊处理

if (distance > r *r)

{for (int m = -1; m <= 1; m++)

{for (int n = -1; n <= 1; n++)

{

pixColor= pixels[(i + m) * width + k +n];

pixR=Color.red(pixColor);

pixG=Color.green(pixColor);

pixB=Color.blue(pixColor);

newR= newR + (int) (pixR *gauss[idx]);

newG= newG + (int) (pixG *gauss[idx]);

newB= newB + (int) (pixB *gauss[idx]);

idx++;

}

}

newR/=delta;

newG/=delta;

newB/=delta;

newR= Math.min(255, Math.max(0, newR));

newG= Math.min(255, Math.max(0, newG));

newB= Math.min(255, Math.max(0, newB));

pixels[i* width + k] = Color.argb(255, newR, newG, newB);

newR= 0;

newG= 0;

newB= 0;

}

}

}

bitmap.setPixels(pixels,0, width, 0, 0, width, height);long end =System.currentTimeMillis();

Log.d("may", "used time="+(end -start));returnbitmap;

}