目标 在这个教程中你将学到如何: 使用OpenCV函数 findContours使用OpenCV函数 drawContours 原理 例程 教程的代码在下面给出. 你也可以从 这里 下载 #include "opencv2/highgui/highgui.hpp" #include "opencv2/imgproc/imgproc.hpp" #include <iostream> #include <stdio.h> #include <stdlib.h> using namespace cv; using namespace std; Mat src; Mat src_gray; int thresh = 100; int max_thresh = 255; RNG rng(12345); /// Function header void thresh_callback(int, void* ); /** @function main */ int main( int argc, char** argv ) { /// 加载源图像 src = imread( argv[1], 1 ); /// 转成灰度并模糊化降噪 cvtColor( src, src_gray, CV_BGR2GRAY ); blur( src_gray, src_gray, Size(3,3) ); /// 创建窗体 char* source_window = "Source"; namedWindow( source_window, CV_WINDOW_AUTOSIZE ); imshow( source_window, src ); createTrackbar( " Canny thresh:", "Source", &thresh, max_thresh, thresh_callback ); thresh_callback( 0, 0 ); waitKey(0); return(0); } /** @function thresh_callback */ void thresh_callback(int, void* ) { Mat canny_output; vector<vector<Point> > contours; vector<Vec4i> hierarchy; /// 用Canny算子检测边缘 Canny( src_gray, canny_output, thresh, thresh*2, 3 ); /// 寻找轮廓 findContours( canny_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) ); /// 绘出轮廓 Mat drawing = Mat::zeros( canny_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, i, color, 2, 8, hierarchy, 0, Point() ); } /// 在窗体中显示结果 namedWindow( "Contours", CV_WINDOW_AUTOSIZE ); imshow( "Contours", drawing ); } 例程说明 结果¶ 原图和检测到的轮廓如下: