OpenCV 90°旋转

顺时针旋转90°思路

原始图像像素矩阵2行2列：

| 1 | 2 |   ---------| 3 | 4 | 

| 1 | 2 |     T        | 1 | 3 |     Y轴镜像    | 3 | 1 |---------   ------->   ---------   ------->    ---------| 3 | 4 |              | 2 | 4 |               | 4 | 2 |

逆时针旋转90°思路

| 1 | 2 |     T        | 1 | 3 |     X轴镜像    | 2 | 4 |---------   ------->   ---------    ------->   ---------| 3 | 4 |              | 2 | 4 |               | 1 | 3 |

OpenCV代码

#include <iostream>#include <string>#include <vector>#include <opencv2/core/core.hpp>#include <opencv2/highgui/highgui.hpp>#include <opencv2/imgproc/imgproc.hpp>using namespace std;using namespace cv;void myRotateClockWise90(Mat &src){    if (src.empty())    {        return;    }    // 矩阵转置    transpose(src, src);     //0: 沿X轴翻转； >0: 沿Y轴翻转； <0: 沿X轴和Y轴翻转    flip(src, src, 1);}void myRotateAntiClockWise90(Mat &src){    if (src.empty())    {        return;    }    transpose(src, src);    flip(src, src, 0);}int main(int argc, char* argv[]){    const string imgpath = "D:/opencv.jpg";    Mat src = imread(imgpath, 1);    Mat srcT;    transpose(src, srcT);    imwrite("D:/opencvT.jpg", srcT);    Mat srcClockWise90 = src.clone();    myRotateClockWise90(srcClockWise90);    imwrite("D:/opencvCW90.jpg", srcClockWise90);    Mat srcAntiClockWise90 = src.clone();    myRotateAntiClockWise90(srcAntiClockWise90);    imwrite("D:/opencvACW90.jpg", srcAntiClockWise90);    return 0;}

测试结果

• 输入图像

• 输入图像的矩阵转置

• 输入图像顺时针旋转90°后的图像

• 输入图像逆时针选择90°后的图像

参考

opencv 图片旋转90度