openCV图像处理笔记C++的创建包围轮廓的矩形和圆形边界框

源码如下：

#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include 
#include 
#include 

using namespace cv;
using namespace std;

// 函数声明
void thresh_callback(int, void*);
//数据说明
Mat src;
Mat src_gray;
int thresh = 100;
int max_thresh = 255;
RNG rng(12345);
int width22 = 2160, higth22 = 1440;	//自定义展示图像的效果图大小
/** @主函数 */
int main()

{
	src = imread("D://xlxl//pp2.jpg", 1);	// 载入原图像, 返回3通道图像
	cvtColor(src, src_gray, COLOR_BGR2GRAY);  // 转化成灰度图像
	blur(src_gray, src_gray, Size(30, 30));	  //灰度图像进行平滑处理

	
	char* source_window01 = "灰度平滑处理图";		// 创建窗口
	namedWindow(source_window01, WINDOW_AUTOSIZE); 	
	resizeWindow(source_window01, width22, higth22);
	moveWindow(source_window01, 0, 0);
	imshow(source_window01, src);


	createTrackbar(" Threshold:", "Source", &thresh, max_thresh, thresh_callback);
	thresh_callback(0, 0);

	waitKey(10);
	return(0);
}


void thresh_callback(int, void*)
{
	Mat threshold_output;
	vector > contours;
	vector hierarchy;

	// 使用Threshold检测边缘
	threshold(src_gray, threshold_output, thresh, 255, THRESH_BINARY);
	
	findContours(threshold_output, contours, hierarchy, RETR_TREE, CHAIN_APPROX_SIMPLE, Point(0, 0));  //找到轮廓

	//多边形逼近轮廓 + 获取矩形和圆形边界框
	vector > contours_poly(contours.size());
	vector boundRect(contours.size());
	vectorcenter(contours.size());
	vectorradius(contours.size());

	for (int i = 0; i < contours.size(); i++)
	{
		approxPolyDP(Mat(contours[i]), contours_poly[i], 3, true);
		boundRect[i] = boundingRect(Mat(contours_poly[i]));
		minEnclosingCircle(contours_poly[i], center[i], radius[i]);
	}
	
	// 画多边形轮廓 + 包围的矩形框 + 圆形框
	Mat drawing = Mat::zeros(threshold_output.size(), CV_8UC3);
	for (int i = 0; i< contours.size(); i++)
	{
		Scalar color = Scalar(rng.uniform(0, 255), rng.uniform(0, 255), rng.uniform(0, 255));
		drawContours(drawing, contours_poly, i, color, 1, 8, vector(), 0, Point());
		rectangle(drawing, boundRect[i].tl(), boundRect[i].br(), color, 2, 8, 0);
		circle(drawing, center[i], (int)radius[i], color, 2, 8, 0);
	}
	// 显示在一个窗口
	/*namedWindow("Contours", WINDOW_AUTOSIZE);
	imshow("Contours", drawing);*/
	char* source_window02 = "检测边框图";		// 创建窗口
	namedWindow(source_window02, WINDOW_AUTOSIZE);
	resizeWindow(source_window02, width22, higth22);
	moveWindow(source_window02,  width22, higth22);
	imshow(source_window02, drawing);
	waitKey(0);
}

原文地址：http://www.opencv.org.cn/opencvdoc/2.3.2/html/doc/tutorials/imgproc/shapedescriptors/bounding_rects_circles/bounding_rects_circles.html、
基本功能
//使用OpenCV函数 boundingRect 来计算包围轮廓的矩形框.
//使用OpenCV函数 minEnclosingCircle 来计算完全包围已有轮廓最小圆.
效果如图：

效果还不错。