android中比较两张图片的相似度

 public static String similarity (Bitmap b,Bitmap viewBt) {
             //把图片转换为Bitmap
      
            Bitmap bm_one = b;
            Bitmap bm_two = viewBt;
             //保存图片所有像素个数的数组，图片宽×高
             int[] pixels_one = new int[bm_one.getWidth()*bm_one.getHeight()];
             int[] pixels_two = new int[bm_two.getWidth()*bm_two.getHeight()];
             //获取每个像素的RGB值
            bm_one.getPixels(pixels_one,0,bm_one.getWidth(),0,0,bm_one.getWidth(),bm_one.getHeight());
            bm_two.getPixels(pixels_two,0,bm_two.getWidth(),0,0,bm_two.getWidth(),bm_two.getHeight());
             //如果图片一个像素大于图片2的像素，就用像素少的作为循环条件。避免报错
             if (pixels_one. length >= pixels_two. length) {
                   //对每一个像素的RGB值进行比较
                   for( int i = 0; i < pixels_two. length; i++){
                int clr_one = pixels_one[i];
                int clr_two = pixels_two[i];
                //RGB值一样就加一（以便算百分比）
                if (clr_one == clr_two) {
                    t++;
                } else {
                               f++;
                           }
            }
            } else {
                   for( int i = 0; i < pixels_one. length; i++){
                int clr_one = pixels_one[i];
                int clr_two = pixels_two[i];
                if (clr_one == clr_two) {
                    t++;
                        } else {
                               f++;
                        }
            }
                  
            }
            
             return "相似度为：" +myPercent ( t, t+ f );
            
      }
    /**
     * 百分比的计算
     * @author xupp
     * @param y(母子)
     * @param z（分子）
     * @return 百分比（保留小数点后两位）
     */
    public static String myPercent (int y, int z)
    {
        String baifenbi= ""; //接受百分比的值
         double baiy=y*1.0;
        double baiz=z*1.0;
        double fen=baiy/baiz;
        DecimalFormat df1 = new DecimalFormat( "00.00%"); //##.00%   百分比格式，后面不足2位的用0补齐
        baifenbi= df1.format(fen);
        return baifenbi;
    }