Java画像の拡大・縮小

<span style="font-size:14px;"><span style="font-size:10px;">p<span style="font-family:Courier New;">ublic void Todouble(){
		int[] doubleData = new int[2*w*2*h];
		for (int y = 0; y < h; y++) {
            for (int x = 0; x < w; x++) {
            	doubleData[2*x + 2*y *2* w] = data[x + y * w];
            }
		}
		
		this.h = 2*h;
		this.w = 2*w;
		for (int y = 0; y < h; y++) {
            for (int x = 0; x < w; x++) {
            	if(y%2 == 1)
            		doubleData[x + y*w] = doubleData[x + (y-1)*w];
            	if(x%2 == 1)
            		doubleData[x + y*w] = doubleData[x-1 + y*w];
            }
		}
		this.data = doubleData;
		
	}</span></span></span>

<span   style="max-width:90%"><span style="font-size:10px;">public void reduce(int a){//a是缩小的<span style="font-family:Times New Roman;">倍数</span>
		int nw = w/a;
		int nh = h/a;
		int[] d = new int[nw*nh];
		
		for (int y = 0; y < nh; y++) {
                  for (int x = 0; x < nw; x++) {
            	   d[x + y*nw] = data[a*x + a*y * w];
                  }
		}
		this.h = nh;
		this.w = nw;
		this.data = d;
	}</span></span>