opencv图片矩形ROI区域矫正

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/qq_36576377/article/details/79604813

void ImgCorrection(Mat imageSource)
{
	Mat image;
	imageSource.copyTo(image);
	GaussianBlur(image, image, Size(3, 3), 0);  //滤波  
	threshold(image, image, 100, 255, CV_THRESH_BINARY);  //二值化  
	imshow("二值化", image);
	Mat element = getStructuringElement(2, Size(7, 7));  //膨胀腐蚀核  

	dilate(image, image, element);

	imshow("膨胀", image);

	Mat image1;
	Laplacian(image, image1, image.depth(), 1);//拉普拉斯变换寻找边界
	imshow("边界", image1);

	//寻找直线  
	vector<Vec2f>lines;
	HoughLines(image1, lines, 1, CV_PI / 150, 60, 0, 0);
	Mat DrawLine = Mat::zeros(image1.size(), CV_8UC1);
	//Mat DrawLine = Mat::zeros(image1.size(), image1.type());
	for (int i = 0; i<lines.size(); i++)
	{
		float rho = lines[i][0];
		float theta = lines[i][1];
		Point pt1, pt2;
		double a = cos(theta), b = sin(theta);
		double x0 = a*rho, y0 = b*rho;
		pt1.x = cvRound(x0 + 1000 * (-b));
		pt1.y = cvRound(y0 + 1000 * a);
		pt2.x = cvRound(x0 - 1000 * (-b));
		pt2.y = cvRound(y0 - 1000 * a);
		line(DrawLine, pt1, pt2, Scalar(255), 1, CV_AA);
	}
	imshow("直线", DrawLine);

	Point2f P1[4];
	Point2f P2[4];
	vector<Point2f>corners;
	goodFeaturesToTrack(DrawLine, corners, 4, 0.1, 10, Mat()); //角点检测  

	cout << "角点坐标：" << endl;

	for (int i = 0; i<corners.size(); i++)//四个角点的坐标
	{
		circle(DrawLine, corners[i], 3, Scalar(255), 3);
		P1[i] = corners[i];
		cout << corners[i].x << " " << corners[i].y << endl;
	}
	imshow("交点", DrawLine);

	P2[0] = Point2f(0, 0);
	P2[1] = Point2f(0, imageSource.rows);
	P2[2] = Point2f(imageSource.cols, imageSource.rows);
	P2[3] = Point2f(imageSource.cols, 0);
	Mat elementTransf;
	elementTransf = getAffineTransform(P1, P2);
	warpAffine(imageSource, imageSource, elementTransf, imageSource.size(), 1, 0, Scalar(255));
	
	imwrite("corrImge.jpg", imageSource);//校正后的图片保存
	
}