C#联合OpenCV（四）图像的旋转、翻转、仿射变换

图像的翻转

 public static void Forexample()
        {
            
            var Src_Images = Cv2.ImRead("lenna.png", ImreadModes.Color);
            var SRC = new Mat();
            var SRC1 = new Mat();
            Cv2.Flip(Src_Images, SRC, FlipMode.X);
            Cv2.Flip(Src_Images, SRC1, FlipMode.Y);
            Cv2.ImShow("1", Src_Images);
            Cv2.ImShow("2", SRC);
            Cv2.ImShow("3", SRC1);
           
        }

可以实现XY的转置翻转 镜像

//转置矩阵
        public static void Transpose(InputArray src, OutputArray dst)
        {
            //需要搭配使用
            Cv2.Flip(src,dst,FlipMode.XY);
            Cv2.Transpose(src, dst);
          
        }

 图像的旋转

rotate 这个算子只能旋转固定的角度。90度180度270度

  public static void Forexample()
        {
            
            var Src_Images = Cv2.ImRead("lenna.png", ImreadModes.Color);
            var SRC = new Mat();
            var SRC1 = new Mat();
            var SRC2 = new Mat();
          

            //90度
            Cv2.Rotate(Src_Images, SRC, RotateFlags.Rotate90Clockwise);
            //180度
            Cv2.Rotate(Src_Images, SRC2, RotateFlags.Rotate180);
            //270度
            Cv2.Rotate(Src_Images, SRC1, RotateFlags.Rotate90Counterclockwise);
            

            Cv2.ImShow("1", Src_Images);
            Cv2.ImShow("2", SRC);
            Cv2.ImShow("3", SRC1);
            Cv2.ImShow("4", SRC2);

        }

 图像的任意角度旋转+仿射变换

//仿射变换
            //方法一  旋转缩放
            //Point center = new Point(SrcImage.Cols / 2, SrcImage.Rows / 2);
            //double angle =0;
            //double scale = 1;
            //Mat rot_mat = Cv2.GetRotationMatrix2D(center, angle, scale);

            //方法二  旋转平移缩放
            Point center = new Point(SrcImage.Cols / 2, SrcImage.Rows / 2);
            double angle = 60.0 / 180.0 * Cv2.PI;//旋转角度，正值表示逆时针旋转
            //旋转平移缩放
            Mat rot_mat = GetTransformRotationMatrix2D(center, 100, 0, 0, 1);
            Mat warp_rotate_dst =new Mat();
            Cv2.WarpAffine(SrcImage, warp_rotate_dst, rot_mat, SrcImage.Size());
            Cv2.ImShow("warp_rotate_dst", warp_rotate_dst);
            Cv2.ImShow("origindst", SrcImage);

 旋转平移封装代码

 public static Mat GetTransformRotationMatrix2D(OpenCvSharp.Point2f center, double Translation_X, double Translation_Y, double Rotate_Angle, double Scale = 1)
        {

            Mat M = Mat.Zeros(2, 3, MatType.CV_64FC1);

            M.At<double>(0, 0) = (double)(Scale * Math.Cos(Rotate_Angle * Math.PI / 180));
            M.At<double>(0, 1) = -(double)(Scale * Math.Sin(Rotate_Angle * Math.PI / 180));
            M.At<double>(1, 0) = (double)(Scale * Math.Sin(Rotate_Angle * Math.PI / 180));
            M.At<double>(1, 1) = (double)(Scale * Math.Cos(Rotate_Angle * Math.PI / 180));

            M.At<double>(0, 2) = (double)((1 - M.At<double>(0, 0)) * center.X - M.At<double>(0, 1) * center.Y + Translation_X);
            M.At<double>(1, 2) = (double)(M.At<double>(0, 1) * center.X + (1 - M.At<double>(0, 0)) * center.Y + Translation_Y);


            return M;
        }

图像的平移

 修改代码

 Mat rot_mat = GetTransformRotationMatrix2D(center, 0, 0, 45, 1);

 图像的旋转