WindowsPhone中在大图中截取小图(图片分割)

 1  private void btnSavePhotos_Click(object sender, RoutedEventArgs e)
 2         {
 3             
 4             WriteableBitmap w1 = new WriteableBitmap(image, null);//截取大图先
 5             //开始循环切图
 6             for (int i = 7; i >=0; i--)
 7             {
 8                 //传递参数到裁剪方法中(大图的位图,小图的起点x和y,长和宽)
 9                 CutImage(w1, (i % 4) * 120, Math.Floor(i / 4) * 120, 120, 120,i);
10             }
11         }
12 
13         private void CutImage(WriteableBitmap wb, double x, double y, double width, double height,int imageId)
14         {
15             // 裁剪方法
16             Image img1 = new Image();
17             img1.Stretch = Stretch.None;
18             //移动大图的起点到小图起点
19             img1.RenderTransform = new TranslateTransform { X = -1 * x, Y = -1 * y };
20             img1.Source = wb;
21             Canvas C = new Canvas();
22             C.Width = width;
23             C.Height = height;
24             C.Children.Add(img1);
25             WriteableBitmap bitmap = new WriteableBitmap(C, null);
26             using (MemoryStream stream = new MemoryStream())
27             {
28                 Extensions.SaveJpeg(bitmap, stream, bitmap.PixelWidth, bitmap.PixelHeight, 0, 100);
29                 using (MediaLibrary library = new MediaLibrary())
30                 {
31                     library.SavePicture("/" + "QQImageWall"  + "-"+ imageId, stream.ToArray());
32                 }
33             }
34         }