寻找并画出轮廓

#include "stdafx.h"
#include "highgui.hpp"
#include "cv.hpp"
#include "iostream"
using namespace cv;
using namespace std;

int main() 
{
//读取图像
Mat img = imread("H:\\contours.png", 0);
//若读取错误，则显示"Load image error！"
if (img.empty())
{
cout << "Load image error!" << endl;
cin.get();
return -1;
}
imshow("source image", img);
//canny边缘检测
Mat edges;
Canny(img, edges, 100, 255);
//寻找轮廓
vector<vector<Point>>contours;
vector<Vec4i>hierarchy;
findContours(edges, contours, hierarchy,CV_RETR_CCOMP,CV_CHAIN_APPROX_SIMPLE,Point());
//画出轮廓
Mat contours_img = Mat::zeros(edges.size(),CV_8UC3);
for (int i = 0; i < contours.size(); i++)
{
Scalar color = Scalar(255, 255, 255, 0);
drawContours(contours_img, contours, i, color,2,8,hierarchy,0,Point());
}
imshow("contours image", contours_img);

while (1) 
{
if (waitKey(15) == 27)
break;
}
return 0;
}