opencv仿射变换

#include <opencv2/opencv.hpp>

/*
功能：对一系列坐标点进行平移仿射变换
参数：
srcPoints:输入点坐标
dstPoints:变换后的点坐标
x:x方向平移的距离
y:y方向平移的距离
*/
void tranlatePoints(std::vector<cv::Point2f>& srcPoints, std::vector<cv::Point2f>& dstPoints,double x,double y)
{
?? ?cv::Mat affineMatrix = (cv::Mat_<double>(2, 3) << 1, 0, x, 0, 1,y);
?? ?cv::transform(srcPoints, dstPoints, affineMatrix);
}

/*
功能：对一系列点进行旋转仿射变换
参数：
srcPoints:输入点坐标
dstPoints:变换后的点坐标
basePoint:旋转基准点
zoomRate:缩放比例，默认为1表示不缩放
*/
void rotatePoints(std::vector<cv::Point2f>& srcPoints, std::vector<cv::Point2f>& dstPoints, cv::Point& basePoint,int degree, float zoomRate=1)
{
?? ?cv::Mat affineMatrix = cv::getRotationMatrix2D(basePoint,degree,zoomRate);
?? ?cv::transform(srcPoints, dstPoints, affineMatrix);
}

/*
功能：对一系列点进行缩放仿射变换
参数：
srcPoints:输入点坐标
dstPoints:变换后的点坐标
basePoint:缩放基准点
zoomRate:缩放比例
*/
void zoomPoints(std::vector<cv::Point2f>& srcPoints, std::vector<cv::Point2f>& dstPoints, cv::Point& basePoint,float zoomRate)
{
?? ?cv::Mat affineMatrix = cv::getRotationMatrix2D(basePoint,0,zoomRate);
?? ?cv::transform(srcPoints, dstPoints, affineMatrix);
}

/*
功能：对一张图片进行平移
参数：
src:要平移的图片
dst:平移的结果
x:x方向平移的距离
y:y方向平移的距离
*/
void translateImage(cv::Mat& src, cv::Mat& dst, double x, double y)
{
?? ?cv::Mat M = (cv::Mat_<double>(2, 3) << 1, 0, x, 0, 1, y);
?? ?cv::warpAffine(src, dst, M, src.size());
}

/*
功能：对一张图片进行旋转
参数：
image:输入图像
imgOut:旋转后的图像
angle:旋转角度
*/
void rotateImage(cv::Mat& image, cv::Mat& imgOut, int angle)
{
?? ?/*
?? ?对旋转的进行改进，由于图形是一个矩形，旋转后的新图像的形状是一个原图像的外接矩形
?? ?因此需要重新计算出旋转后的图形的宽和高
?? ?*/
?? ?int width = image.cols;
?? ?int height = image.rows;

?? ?double radian = angle * CV_PI / 180.;//角度转换为弧度
?? ?double width_rotate = fabs(width*cos(radian)) + fabs(height*sin(radian));
?? ?double height_rotate = fabs(width*sin(radian)) + fabs(height*cos(radian));

?? ?//旋转中心 原图像中心点
?? ?cv::Point2f center((float)width / 2.0, (float)height / 2.0);
?? ?//旋转矩阵
?? ?cv::Mat m1 = cv::getRotationMatrix2D(center, angle, 1.0);
?? ?//m1为2行3列通道数为1的矩阵
?? ?//变换矩阵的中心点相当于平移一样 原图像的中心点与新图像的中心点的相对位置
?? ?m1.at<double>(0, 2) += (width_rotate - width) / 2.;
?? ?m1.at<double>(1, 2) += (height_rotate - height) / 2.;
?? ?if (image.channels() == 1)
?? ?{
?? ??? ?cv::warpAffine(image, imgOut, m1, cv::Size(width_rotate, height_rotate), cv::INTER_LINEAR, 0, cv::Scalar(0));
?? ?}
?? ?else if (image.channels() == 3)
?? ?{
?? ??? ?cv::warpAffine(image, imgOut, m1, cv::Size(width_rotate, height_rotate), cv::INTER_LINEAR, 0, cv::Scalar(0,0,0));
?? ?}
}

/*
功能：对一张图片进行缩放
参数：
src:输入图像
dst:缩放后的图像
basePoint:缩放基准点
zoomRate:缩放比例
*/
void zoomImage(cv::Mat& src, cv::Mat& dst, cv::Point& rotaPoint, float zoomRate)
{
?? ?cv::Mat M = cv::getRotationMatrix2D(rotaPoint, 0, zoomRate);
?? ?cv::warpAffine(src, dst, M, src.size());
}

//#define TESTPOINTS
#define TESTIMAGE

int main() {
#ifdef TESTPOINTS
?? ?// 创建原始点集
?? ?std::vector<cv::Point2f> srcPoints = { cv::Point2f(100, 100), cv::Point2f(200, 200), cv::Point2f(300, 300) };
?? ?//变换点集
?? ?std::vector<cv::Point2f> dstPoints;
?? ?//tranlatePoints(srcPoints, dstPoints, 10, 10);
?? ?cv::Point point(0, 0);
?? ?//rotatePoints(srcPoints, dstPoints, point,180);
?? ?//zoomPoints(srcPoints, dstPoints, point, 0.5);

?? ?// 输出结果
?? ?std::cout << "原始点集: ";
?? ?for (const auto& point : srcPoints) {
?? ??? ?std::cout << point << " ";
?? ?}
?? ?std::cout << std::endl;

?? ?std::cout << "仿射变换后的点集: ";
?? ?for (const auto& point : dstPoints) {
?? ??? ?std::cout << point << " ";
?? ?}
?? ?std::cout << std::endl;
#endif // TESTPOINTS

#ifdef TESTIMAGE
?? ?cv::Mat img1 = cv::imread("D:/20240103141532.png");
?? ?cv::Mat dst;
?? ?//translateImage(img1, dst, -50, 50);
?? ?//cv::imshow("src",img1);
?? ?//cv::imshow("1", dst);
?? ?//cv::waitKey(0);
?? ?
?? ?//for (int i = 0; i < 36; i++)
?? ?//{
?? ?//?? ?rotateImage(img1, dst,i * 10);
?? ?//?? ?cv::imshow("1", dst);
?? ?//?? ?cv::waitKey(0);
?? ?//}

?? ?//int width = img1.cols;
?? ?//int height = img1.rows;
?? ?//cv::Point basePoint((float)width / 2.0, (float)height / 2.0);
?? ?//zoomImage(img1, dst, basePoint, 0.5);
?? ?//cv::imshow("src", img1);
?? ?//cv::imshow("1", dst);
?? ?//cv::waitKey(0);
#endif // TESTIMAGE
?? ?return 0;
}