OpenCV3之——图像仿射变换warpAffine()和getRotationMatrix2D()

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#include <opencv2/opencv.hpp>
#include <iostream>
using namespace std;
using namespace cv;

#define WINDOW_NAME1 "原始图窗口"
#define WINDOW_NAME2 "经过warp后的图像"
#define WINDOW_NAME3 "经过warp和rotate后的图像"

int main() {
	system("color 1A");
	//定义两组点，表示两个三角形
	Point2f srcTriangle[3];
	Point2f dstTriangle[3];

	//定义一些Mat变量
	Mat rotMat(2, 3, CV_32FC1);
	Mat warpMat(2, 3, CV_32FC1);
	Mat srcImage, dstImage_warp, dstImage_warp_rotate;

	srcImage = imread("1.jpg",1);
	if (!srcImage.data) {
		printf("读取图片错误！\n");
		return false;
	}
	dstImage_warp = Mat::zeros(srcImage.rows, srcImage.cols, srcImage.type());

	//设置源图像和目标图像上的三组点以计算仿射变换
	srcTriangle[0] = Point2f(0, 0);
	srcTriangle[1] = Point2f(static_cast<float>(srcImage.cols - 1), 1);
	srcTriangle[2] = Point2f(0, static_cast<float>(srcImage.rows - 1));

	dstTriangle[0] = Point2f(static_cast<float>(srcImage.cols*0.0), static_cast<float>(srcImage.rows*0.33));
	dstTriangle[1] = Point2f(static_cast<float>(srcImage.cols*0.65), static_cast<float>(srcImage.rows*0.35));
	dstTriangle[2] = Point2f(static_cast<float>(srcImage.cols*0.15), static_cast<float>(srcImage.rows*0.6));

	//求得仿射变换
	warpMat = getAffineTransform(srcTriangle, dstTriangle);

	//对原图像应用上面求得的仿射变换
	warpAffine(srcImage, dstImage_warp, warpMat, dstImage_warp.size());

	//对图像进行缩放后再旋转
	//计算绕图像中心顺时针旋转50度缩放因子为0.6的旋转矩阵
	Point center = Point(dstImage_warp.cols / 2, dstImage_warp.rows / 2);
	double angle = -30.0;
	double scale = 0.8;
	//通过上面的旋转细节信息求得选装矩阵
	rotMat = getRotationMatrix2D(center, angle, scale);

	//旋转已缩放后的图像
	warpAffine(dstImage_warp, dstImage_warp_rotate, rotMat, dstImage_warp.size());

	//显示结果
	imshow(WINDOW_NAME1, srcImage);
	imshow(WINDOW_NAME2, dstImage_warp);
	imshow(WINDOW_NAME3, dstImage_warp_rotate);

	waitKey(0);
	return 0;
}