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图像平移：

　　　　　　1.不改变图像大小

　　　　　　 2.改变图像大小

 编程按照目标图像的角度去编写

不改变大小的平移  1 void imageTranslation1(Mat& src, Mat& dst, const int& xoffset, const int& yoffset) 2 { 3     cvtColor(src, src, CV_BGR2GRAY); 4     const int height = src.rows; 5     const int width  = src.cols; 6     dst.create(src.size(), src.type()); 7     dst.setTo(0); 8     for (size_t i = 0; i < height; i++) 9     {10         for (size_t j = 0; j < width; j++)11         {12             int x = j - xoffset;//列x=j13             int y = i - yoffset;//行y=i14             if (x >= 0 && y >= 0 && x <= width && y <= height)15             {16                 dst.at
     
      (i, j) = src.at
      
       (y, x);17             }18         }19     }20 }
      
     

 

//----改变图像大小的平移void imageTranslation2(Mat& src, Mat& dst, const int& xoffset, const int& yoffset){    cvtColor(src, src, CV_BGR2GRAY);    dst.create(Size(src.cols + abs(xoffset), src.rows + abs(yoffset)), src.type());    dst.setTo(0);    const int height = dst.rows;    const int width  = dst.cols;    for (size_t i = 0; i < height; i++)    {        for (size_t j = 0; j < width; j++)        {            int x = j - xoffset;//列x=j            int y = i - yoffset;//行y=i            if (x >= 0 && y >= 0 && x <= width && y <= height)            {                dst.at
     
      (i, j) = src.at
      
       (y, x);            }        }    }}
      
     

 

 

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图像的缩放：

　　　　　　　　　　1.基于等间隔提取图像缩放

　　　　　　 　2.基于区域子块提取图像缩放

等间隔  1 void imageReduction1(Mat& src, Mat& dst, float kx, float ky) 2 { 3      4     cvtColor(src, src, CV_BGR2GRAY); 5     dst.create(Size(cvRound(src.cols*kx), cvRound(src.rows*ky)), src.type()); 6     const int height = dst.rows; 7     const int width  = dst.cols; 8     dst.setTo(0); 9     for (size_t i = 0; i < height; i++)10     {11         for (size_t j = 0; j < width; j++)12         {13             int y = static_cast
     
      ((i + 1) / kx);14             int x = static_cast
      
       ((j + 1) / ky);15             dst.at
       
        (i, j) = src.at
        
         (y, x);16         }17     }18 }
        
       
      
     

区域子块  1 void imageReduction2(Mat& src, Mat& dst, float kx, float ky) 2 { 3  4     cvtColor(src, src, CV_BGR2GRAY); 5     dst.create(cvRound(src.rows*ky), cvRound(src.cols*kx), src.type()); 6     int height = src.rows; 7     int width  = src.cols; 8     dst.setTo(0); 9     const int dx = cvRound(1 / kx);10     const int dy = cvRound(1 / ky);11     for (size_t i = 0, x = 0; i < height; i += dy, x++)12     {13         for (size_t j = 0, y = 0; j < width; j += dx, y++)14         {15             dst.at
     
      (x,y) = areaAverage(src, Point(j, i), Point(j + dx, i + dy));16         }17     }18 19 }20 //--------求一个矩形区域像素平均值21 uchar areaAverage(Mat& src, Point& leftPoint, Point& rightPoint)22 {23     Mat roi = src(Rect(leftPoint, rightPoint));24     const int height = roi.rows;25     const int width  = roi.cols;26     float sumPix = 0;27     for (size_t i = 0; i < height; i++)28     {29         for (size_t j = 0; j < width; j++)30         {31             sumPix += (roi.at
      
       (i, j) / (height*width));32         }33     }34     return sumPix;35 }
      
     

 

 图像旋转

　　　　　　　没怎么看懂书上的代码