1   /// <summary>
 2 
 3         /// 比较两张图片的像素，确定阴影图片位置
 4 
 5         /// </summary>
 6 
 7         /// <param name="oldBmp"></param>
 8 
 9         /// <param name="newBmp"></param>
10 
11         /// <returns></returns>
12 
13         public static int GetArgb(Bitmap oldBmp, Bitmap newBmp)
14 
15         {
16 
17             //由于阴影图片四个角存在黑点(矩形1*1)
18 
19             for (int i = 0; i < newBmp.Width; i++)
20 
21             {
22 
23  
24 
25                 for (int j = 0; j < newBmp.Height; j++)
26 
27                 {
28 
29                     if ((i>=0&&i<=1)&&((j>=0&&j<=1)||(j>= (newBmp.Height-2)&&j<=(newBmp.Height - 1))))
30 
31                     {
32 
33                         continue;
34 
35                     }
36 
37                     if ((i >= (newBmp.Width-2) && i <= (newBmp.Width - 1)) && ((j >= 0 && j <= 1) || (j >= (newBmp.Height - 2) && j <= (newBmp.Height - 1))))
38 
39                     {
40 
41                         continue;
42 
43                     }
44 
45                  
46 
47                     //获取该点的像素的RGB的颜色
48 
49                     Color oldColor = oldBmp.GetPixel(i, j);
50 
51                     Color newColor = newBmp.GetPixel(i, j);
52 
53                     if (Math.Abs(oldColor.R - newColor.R) > 60 || Math.Abs(oldColor.G - newColor.G) > 60 || Math.Abs(oldColor.B - newColor.B) > 60)
54 
55                     {
56 
57                         return i;
58 
59                     }
60 
61  
62 
63  
64 
65                 }
66 
67             }
68 
69             return 0;
70 
71         }
72 
73