OpenCV学习7

一 学习内容

1 绘制直线

2 绘制曲线

3 添加文本

4 绘制N条随机直线

二 代码

#include <opencv2/opencv.hpp>
#include <iostream>

using namespace std;
using namespace cv;

Mat dst;
void MyLines();
void Rectangle();
void MyEllipse();
void MyCircle();
void MyPolygon();
void MyRandomLines();
int main(int argc, char** argv) {
	Mat src2;
	src2 = imread("e:/2 opencv_projects_zl/desk4.jpg");

	if (!src2.data) {
		cout << "Load Image Desk2 Error...\n" << endl;
		return -1;
	}
	char Figure_name[] = "Figure1";
	namedWindow(Figure_name, CV_WINDOW_AUTOSIZE);
	imshow(Figure_name, src2);

	// 学习新内容
	//1. 生成一张背景图，并在背景图上绘制线
	//dst = Mat::zeros(src2.size(),src2.type());
	dst = Mat(src2.size(), src2.type());
	dst = Scalar(50, 80, 20);
	//绘线
	MyLines();
	Rectangle();
	MyEllipse();
	MyCircle();
	MyPolygon();
	//添加文本
	putText(dst,"World!", Point(dst.cols / 2 -50, dst.rows / 2),CV_FONT_HERSHEY_COMPLEX,1.0,Scalar(200,220,60),3,8);
	char Figure_name2[] = "Figure2";
	namedWindow(Figure_name2, CV_WINDOW_AUTOSIZE);
	imshow(Figure_name2, dst);

	//绘制随机直线
	MyRandomLines();

	waitKey(0);
	return 0;
}

void MyLines() {//绘制直线
	Point p1 = Point(20, 30);
	Point p2;
	p2.x = 20;
	p2.y = 300;

	Scalar color = Scalar(0, 0, 255);
	//line(dst,p1,p2,color,1,LINE_8);
	line(dst, p1, p2, color, 1, LINE_AA);//更改线型
}

void Rectangle() {//绘制矩形
	Rect rect = Rect(20,30,50,30);//起始位置为x=20,y=30，宽和高分别为50,30
	Scalar color_rect = Scalar(255, 0, 0);
	rectangle(dst,rect,color_rect,1,LINE_4);
}

void MyEllipse() {//绘制椭圆
	Scalar color_ellipse = Scalar(0, 255, 0);
	ellipse(dst,Point(dst.cols/2,dst.rows/2),Size(dst.cols/4,dst.rows/8),0,0,360, color_ellipse,2,LINE_8);// 倾斜度0度，圆弧起始度为0，结束角度为360
	ellipse(dst, Point(dst.cols / 2, dst.rows / 2), Size(dst.cols / 4, dst.rows / 8), 45, 0, 360, color_ellipse, 2, LINE_8);// 倾斜度45度
	ellipse(dst, Point(dst.cols / 2, dst.rows / 2), Size(dst.cols / 4, dst.rows / 8), 90, 0, 360, color_ellipse, 2, LINE_8);// 倾斜度90度
	ellipse(dst, Point(dst.cols / 2, dst.rows / 2), Size(dst.cols / 4, dst.rows / 8), 135, 0, 360, color_ellipse, 2, LINE_8);// 倾斜度135度
}

void MyCircle() {//绘制圆
	Scalar color_circle = Scalar(0, 255, 255);
	Point Central_Point = Point(dst.cols / 2 , dst.rows / 2 );
	int radius = dst.cols / 4;
	circle(dst,Central_Point, radius, color_circle,3,LINE_4);
	
}

void MyPolygon() {//绘制多边形
	Point pts[1][5];
	pts[0][0] = Point(60,80);
	pts[0][1] = Point(60, 100);
	pts[0][2] = Point(80, 100);
	pts[0][3] = Point(80, 80);
	pts[0][4] = Point(60, 80);

	const Point* ppts[] = {pts[0]};
	int npt[]= {5};
	Scalar color_poly = Scalar(255, 255, 0);
	fillPoly(dst,ppts,npt,1,color_poly,8);

}

void MyRandomLines() {//绘制随机直线
	RNG rng(123456);//随机数总值?
	Point pt1;
	Point pt2;
	Mat dst2 = Mat::zeros(dst.size(),dst.type());
	char Figure_name3[] = "Figure3";
	namedWindow(Figure_name3, CV_WINDOW_AUTOSIZE);
	for (size_t i = 0; i < 100; i++)
	{
		pt1.x = rng.uniform(0,dst.cols);
		pt2.x = rng.uniform(0, dst.cols);
		pt1.y = rng.uniform(0, dst.rows);
		pt2.y = rng.uniform(0, dst.rows);

		Scalar color_random = Scalar(rng.uniform(0,255), rng.uniform(0, 255), rng.uniform(0, 255));
		if (waitKey(50)>0) {
			break;
		}
		line(dst2,pt1,pt2,color_random,1,8);
		imshow(Figure_name3, dst2);
	}

}

三 调试结果