1 using System;
 2 using System.IO;
 3 using System.Drawing;    
 4 
 5 class MainClass
 6     {
 7         public static void Main(string[] args)
 8         {
 9             //图片一的文件路径
10             Stream blackImageReader = new FileStream("/Users/shiyidu/Desktop//1.jpg", FileMode.Open);
11             Bitmap blackImage = new Bitmap(blackImageReader);
12 
13             //图片二的文件路径
14             Stream whiteImageReader = new FileStream("/Users/shiyidu/Desktop//2.jpg", FileMode.Open);
15             Bitmap whiteImage = new Bitmap(whiteImageReader);
16 
17             //生成最终图片
18             Bitmap finalImage = CalculateHiddenImage(blackImage, whiteImage);
19 
20             //最终图片保存路径
21             Stream imageCreater = new FileStream("/Users/shiyidu/Desktop//final.png", FileMode.Create);
22             finalImage.Save(imageCreater, System.Drawing.Imaging.ImageFormat.Png);
23         }
24 
25         private static Bitmap CalculateHiddenImage(Bitmap blackImage, Bitmap whiteImage)
26         {
27             int b_width = blackImage.Width;
28             int b_height = blackImage.Height;
29             int w_width = whiteImage.Width;
30             int w_height = whiteImage.Height;
31 
32             //设定最终图片的尺寸
33             int f_width = Math.Max(b_width, w_width);
34             int f_height = Math.Max(b_height, w_height);
35 
36             Bitmap result = new Bitmap(f_width, f_height);
37 
38             //黑色图片距离边缘的距离
39             int b_widthOffset = b_width == f_width ? 0 : (f_width - b_width) / 2;
40             int b_heightOffset = b_height == f_height ? 0 : (f_height - b_height) / 2;
41 
42             //白色图片离边缘距离
43             int w_widthOffset = w_width == f_width ? 0 : (f_width - w_width) / 2;
44             int w_heightOffset = w_height == f_height ? 0 : (f_height - w_height) / 2;
45 
46             for (int x = 0; x < f_width; x++) {
47                 for (int y = 0; y < f_height; y++) {
48                     //上下左右交叉排列黑白像素
49                     bool blackPixel = (x + y) % 2 == 0 ? true : false;
50 
51                     int coor_x;
52                     int coor_y;
53                     //决定当前像素位置是否对应图一或图二某像素，如果没有，跳过循环
54                     bool validPixel = true;
55                     if (blackPixel) {
56                         coor_x = x - b_widthOffset;
57                         if (coor_x > b_width - 1) validPixel = false;
58                         coor_y = y - b_heightOffset;
59                         if (coor_y > b_height - 1) validPixel = false;
60                     } else {
61                         coor_x = x - w_widthOffset;
62                         if (coor_x > w_width - 1) validPixel = false;
63                         coor_y = y - w_heightOffset;
64                         if (coor_y > w_height - 1) validPixel = false;
65                     }
66 
67                     validPixel = validPixel && coor_x >= 0 && coor_y >= 0;
68                     if (!validPixel) continue;
69 
70                     //根据颜色计算像素灰度，设定透明度
71                     if (blackPixel) {
72                         Color origin = blackImage.GetPixel(coor_x, coor_y);
73                         int gray = (origin.R * 19595 + origin.G * 38469 + origin.B * 7472) >> 16;
74                         Color finalColor = Color.FromArgb(255 - gray, Color.Black);
75                         result.SetPixel(x, y, finalColor);
76                     } else {
77                         Color origin = whiteImage.GetPixel(coor_x, coor_y);
78                         int gray = (origin.R * 19595 + origin.G * 38469 + origin.B * 7472) >> 16;
79                         Color finalColor = Color.FromArgb(gray, Color.White);
80                         result.SetPixel(x, y, finalColor);
81                     }
82                 }
83             }
84 
85             return result;
86         }
87     }