OpenCV之凸包检测基础

凸包

 

convecHull()函数

代码

生成若干个坐标值随机的彩色点, 用convexHull函数对点连接起来的图形球凸包

#include 
#include   
#include  

using namespace cv;
using namespace std;


int main()
{
	//初始化变量和随机值
	Mat image(600, 600, CV_8UC3);
	RNG& rng = theRNG();

	//循环,按下ESC,Q,q键程序退出,否则有键按下便一直更新
	while (1)
	{
		//参数初始化
		char key;//键值
		int count = (unsigned)rng % 100 + 3;//随机生成点的数量
		vector points; //点值

		//随机生成点坐标
		for (int i = 0; i < count; i++)
		{
			Point point;
			point.x = rng.uniform(image.cols / 4, image.cols * 3 / 4);
			point.y = rng.uniform(image.rows / 4, image.rows * 3 / 4);
			points.push_back(point);
		}

		//检测凸包
		vector hull;
		convexHull((points), hull, true);

		//绘制出随机颜色的点
		for (int i = 0; i < count; i++)
		{
			circle(image, points[i], 3, Scalar(rng.uniform(0, 255), rng.uniform(0, 255), rng.uniform(0, 255)), FILLED, LINE_8);
		}
		int hullcount = (int)hull.size(); // 凸包的边数
		Point point0 = points[hull[hullcount - 1]]; //连接凸包边的坐标点

		//绘制凸包的边
		for (int i = 0; i < hullcount; i++)
		{
			Point point = points[hull[i]];
			line(image, point0, point, Scalar(255, 255, 255), 2, LINE_8);
			point0 = point;
		}
		
		//显示效果图
		imshow("凸包检测示例", image);

		//按下ESC,Q,或者q, 程序退出
		key = (char)waitKey();
		if (key == 27 || key == 'q' || key == 'Q')
		{
			break;
		}
	}

	waitKey(0);
	return 0;
}

效果