java 图像卷积运算，高斯模糊以及拉普拉斯算子

public void filter(double[][] mask) {
		toGray();//灰度化
		int mh = mask.length;
		int mw = mask[1].length;
		int sh = (mh+1)/2;
		int sw = (mw+1)/2;
		double maskSum = math.sum(mask);
		int[] d= new int[w*h];
		
		for(int i=(mh-1)/2+1;i<h-(mh-1)/2;i++){
			for(int j=(mw-1)/2+1;j<w-(mw-1)/2;j++){
				
			   int s = 0;
		       for(int m=0; m<mh ; m++){
		    	   for(int n=0;n<mw;n++){
		    		   s = s + (int)(mask[m]
*this.data[j+n-sw +(i+m-sh)*w]);
		    	   }
		       }
		       
		       if(maskSum != 0)
		    	   s /= maskSum;
		       
		       if(s < 0)
		    	   s =0;
		       if(s > 255)
		    	   s = 255;
		       d[j + i * w] = s;   
			}
		}
		
		this.data = d;
	}