圖像的縮放

	resize(image, image, Size(round(image.cols * 0.5), round(image.rows * 0.5)));

?輸入圖像 輸出圖像 大小變換

canny邊緣算子的使用

	cvtColor(image, gray, COLOR_BGR2GRAY);
	Canny(gray, canny_mat, 40, 100);

?必須先轉(zhuǎn)化為灰度圖，作為輸入 超過100是真的邊緣 低于40是確定不是邊緣 在中間若連接邊緣 則為邊緣?

普通旋轉(zhuǎn)縮放變換（仿射變換）

?獲取仿射變換矩陣

	float angel = -10.0, scale = 1;
	Mat dstmat;
	Point2f center(image.cols * 0.5, image.rows * 0.5);
	Mat affine_matrix = getRotationMatrix2D(center, angel, scale);

獲取仿射變換的矩陣 中心點(diǎn) 旋轉(zhuǎn)角度 大小是否變換

-10是順時(shí)針轉(zhuǎn)

仿射變換函數(shù)

warpAffine(image, dstmat, affine_matrix,image.size());

輸入圖 輸出圖 仿射變換矩陣 畫布的大小?

這樣的仿射變換有旋轉(zhuǎn)的缺陷，因?yàn)榇笮『驮瓐D一樣，但旋轉(zhuǎn)后，外接矩形肯定大于原圖，所以溢出的部分會看不到，后期會更新改進(jìn)版

點(diǎn)到點(diǎn)的仿射變換（6變量?所以要3個點(diǎn)對3個點(diǎn)）

	Mat affine_Mat;
	const cv::Point2f src_pt[] = {
		  cv::Point2f(100,100),
		  cv::Point2f(20,30),
		  cv::Point2f(70,90),
	};
	const cv::Point2f warp_pt[] = {
		  cv::Point2f(50,100),
		  cv::Point2f(50,20),
		  cv::Point2f(70,96),
	};

	Mat affine_matrix2 = cv::getAffineTransform(src_pt, warp_pt);

	warpAffine(image, affine_Mat, affine_matrix2,image.size());

一個點(diǎn)對應(yīng)一個點(diǎn)?

計(jì)算機(jī)會幫我們求出仿射變換的矩陣

點(diǎn)到點(diǎn)的透射變換（8變量?所以要4個點(diǎn)對4個點(diǎn)）

	Mat perspective_Mat;
	cv::Point2f pts1[] = {
		cv::Point2f(150,150),
		cv::Point2f(150,300),
		cv::Point2f(350,300),
		cv::Point2f(350,150),

	};
	cv::Point2f pts2[] = {
	cv::Point2f(200,150),
	cv::Point2f(200,300),
	cv::Point2f(340,270),
	cv::Point2f(340,180),
	};

	Mat perspective_matrix = cv::getPerspectiveTransform(pts1, pts2);
	warpPerspective(image, perspective_Mat, perspective_matrix, image.size());

?總體代碼：文章來源地址http://www.zghlxwxcb.cn/news/detail-628252.html

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


int main() {
	Mat image = imread("lena.jpeg");
	imshow("lena", image);
	waitKey(0);
	cvDestroyAllWindows();

	resize(image, image, Size(round(image.cols * 0.5), round(image.rows * 0.5)));
	imshow("lena", image);
	waitKey(0);
	cvDestroyAllWindows();

	Mat gray;
	Mat canny_mat;
	cvtColor(image, gray, COLOR_BGR2GRAY);
	Canny(gray, canny_mat, 40, 100);
	imshow("canny_mat", canny_mat);
	waitKey(0);
	cvDestroyAllWindows();	

	float angel = -10.0, scale = 1;
	Mat dstmat;
	Point2f center(image.cols * 0.5, image.rows * 0.5);
	Mat affine_matrix = getRotationMatrix2D(center, angel, scale);
	warpAffine(image, dstmat, affine_matrix,image.size());
	imshow("dstmat", dstmat);
	waitKey(0);
	cvDestroyAllWindows();


	Mat affine_Mat;
	const cv::Point2f src_pt[] = {
		  cv::Point2f(100,100),
		  cv::Point2f(20,30),
		  cv::Point2f(70,90),
	};
	const cv::Point2f warp_pt[] = {
		  cv::Point2f(50,100),
		  cv::Point2f(50,20),
		  cv::Point2f(70,96),
	};

	Mat affine_matrix2 = cv::getAffineTransform(src_pt, warp_pt);

	warpAffine(image, affine_Mat, affine_matrix2,image.size());
	imshow("affine_Mat", affine_Mat);
	waitKey(0);
	cvDestroyAllWindows();



	Mat perspective_Mat;
	cv::Point2f pts1[] = {
		cv::Point2f(150,150),
		cv::Point2f(150,300),
		cv::Point2f(350,300),
		cv::Point2f(350,150),

	};
	cv::Point2f pts2[] = {
	cv::Point2f(200,150),
	cv::Point2f(200,300),
	cv::Point2f(340,270),
	cv::Point2f(340,180),
	};

	Mat perspective_matrix = cv::getPerspectiveTransform(pts1, pts2);
	warpPerspective(image, perspective_Mat, perspective_matrix, image.size());
	imshow("perspective_Mat", perspective_Mat);
	waitKey(0);
	cvDestroyAllWindows();

	//疑問 圖像的平移如何實(shí)現(xiàn)  image.size（）是什么個東西 如何改變圖像大小？


	
	return 0;
}

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