用C#怎么实现图像的分块?

用C#怎么实现图像的分块?
用C#怎么实现图像的分块?

用C#怎么实现图像的分块?
实现思路
.NET Framework GDI+ 为我们提供了一组丰富地类来编辑图形图像.有关.NET Framework GDI+的详细资料请查阅msdn相关文档.这里只简要叙述本程序要用的的几个类.
System.Drawing.Image.LoadFile 方法可以从指定的文件创建 Image 对象.System.Drawing.Image.Save方法可以将此 Image 对象保存到指定文件.System.Drawing.Image.Width和System.Drawing.Image.Height属性可以得到图片的宽度和高度.
System.Drawing.Graphics类可以编辑图像.System.Drawing.Graphics.DrawImage方法在指定位置并且按指定大小绘制指定的 Image 对象的指定部分.
图片分隔说明：就是把一张大图,按指定的宽度和高度分隔成一组小块
对初学者的提示：在我们读书时学过的数学坐标如图2所示,在GDI＋里的坐标如图3所示
3.实现代码
1public class CropImageManipulator
2 {
3 public CropImageManipulator()
4 {
5
6 }
7
8 // 不含扩展名的文件名
9 private string _fileNameWithoutExtension;
10 // 文件扩展名
11 private string _fileExtension;
12 // 文件所属的文件夹
13 private string _fileDirectory;
14 public string Cropping(string inputImgPath,int cropWidth,int cropHeight)
15 {
16 this._fileNameWithoutExtension = System.IO.Path.GetFileNameWithoutExtension(inputImgPath);
17 this._fileExtension = System.IO.Path.GetExtension(inputImgPath);
18 this._fileDirectory = System.IO.Path.GetDirectoryName(inputImgPath);
19
20 // 装载要分隔的图片
21 Image inputImg = Image.FromFile(inputImgPath);
22 int imgWidth = inputImg.Width;
23 int imgHeight = inputImg.Height;
24
25 // 计算要分几格
26 int widthCount = (int)Math.Ceiling((imgWidth * 1.00) / (cropWidth * 1.00));
27 int heightCount = (int)Math.Ceiling((imgHeight * 1.00) / (cropHeight * 1.00));
28 //----------------------------------------------------------------------
29 ArrayList areaList = new ArrayList();
30
31 System.Text.StringBuilder sb = new System.Text.StringBuilder();
32 sb.Append("

");
33 sb.Append(System.Environment.NewLine);
34
35 int i = 0;
36 for (int iHeight = 0; iHeight < heightCount ; iHeight ++)
37 {
38 sb.Append("");
39 sb.Append(System.Environment.NewLine);
40 for (int iWidth = 0; iWidth < widthCount ; iWidth ++)
41 {
42 //string fileName = "";
43 string fileName = string.Format("",this._fileNameWithoutExtension,i,this._fileExtension);
44 sb.Append("");
45 sb.Append(System.Environment.NewLine);
46
47
48 int pointX = iWidth * cropWidth;
49 int pointY = iHeight * cropHeight;
50 int areaWidth = ((pointX + cropWidth) > imgWidth) (imgWidth - pointX) :cropWidth;
51 int areaHeight = ((pointY + cropHeight) > imgHeight) (imgHeight - pointY) :cropHeight;
52 string s = string.Format("{0};{1};{2};{3}",pointX,pointY,areaWidth,areaHeight);
53
54 Rectangle rect = new Rectangle(pointX,pointY,areaWidth,areaHeight);
55 areaList.Add(rect);
56 i ++;
57 }
58 sb.Append("");
59 sb.Append(System.Environment.NewLine);
60 }
61
62 sb.Append("

" + fileName + "

");
63
64
65 //----------------------------------------------------------------------
66
67 for (int iLoop = 0 ; iLoop < areaList.Count ; iLoop ++)
68 {
69 Rectangle rect = (Rectangle)areaList[iLoop];
70 string fileName = this._fileDirectory + "\\" + this._fileNameWithoutExtension + "_" + iLoop.ToString() + this._fileExtension;
71 Bitmap newBmp = new Bitmap(rect.Width,rect.Height,PixelFormat.Format24bppRgb);
72 Graphics newBmpGraphics = Graphics.FromImage(newBmp);
73 newBmpGraphics.DrawImage(inputImg,new Rectangle(0,0,rect.Width,rect.Height),rect,GraphicsUnit.Pixel);
74 newBmpGraphics.Save();
75 switch (this._fileExtension.ToLower())
76 {
77 case ".jpg":
78 case ".jpeg":
79 newBmp.Save(fileName,ImageFormat.Jpeg);
80 break;
81 case "gif":
82 newBmp.Save(fileName,ImageFormat.Gif);
83 break;
84 }
85
86 }
87 inputImg.Dispose();
88 string html = sb.ToString();
89 return html;
90 }
91
92 }