通过C++ wrapper实现访问图像像素

 1 template<class T> class Image
 2 {
 3     private:
 4         IlpImage *imgp;
 5     public:
 6         Image(IplImage* img = 0)
 7         {
 8             imgp = img;
 9         }
10         inline T* operator[](const int rowIndx)
11         {
12             return( (T*)(imgp ->imageData + rowIndx * imgp ->widthStep));
13         }
14 };
15 
16 typedef struct {
17     unsigned char b, g, r;
18 }RgbPixel;
19 
20 typedef struct {
21     float b, g, r;
22 }RgbPixelFloat;
23 
24 typedef Image<RgbPixel>      RgbImage;
25 typedef Imgae<RgbPixelFloat> RgbImageFloat;
26 typedef Image<unsigned char> BwImage;
27 typedef Image<float>         BwImageFloat;

例：对3通道的字节型图像访问如下：

1 IplImage* img = cvCreateImage(cvSize(640, 480), IPL_DEPTH_8U, 3);
2 RgbImage imgA(img);
3 //假设访问第K通道、第i行、第j列的像素
4 imgA[i][j].b = 111;
5 imgA[i][j].g = 111;
6 imgA[i][j].r = 111;