#include "opencv2/imgproc/imgproc.hpp"#include "opencv2/highgui/highgui.hpp"#include <math.h>#include <iostream>using namespace cv;using namespace std;static void help(){    cout    << "\nThis program illustrates the use of findContours and drawContours\n"    << "The original image is put up along with the image of drawn contours\n"    << "Usage:\n"    << "./contours2\n"    << "\nA trackbar is put up which controls the contour level from -3 to 3\n"    << endl;}const int w = 500;int levels = 3;vector<vector<Point> > contours;vector<Vec4i> hierarchy;static void on_trackbar(int, void*){    Mat cnt_img = Mat::zeros(w, w, CV_8UC3);    int _levels = levels - 3;    drawContours( cnt_img, contours, _levels <= 0 ? 3 : -1, Scalar(128,255,255),                  3, LINE_AA, hierarchy, std::abs(_levels) );    imshow("contours", cnt_img);}int main( int argc, char** argv){    cv::CommandLineParser parser(argc, argv, "{help h||}");    if (parser.has("help"))    {        help();        return 0;    }//    Mat img = Mat::zeros(w, w, CV_8UC1);    //Jeff --> we don‘t need to draw this by ourselves.    //Draw 6 faces//    for( int i = 0; i < 6; i++ )//    {//        int dx = (i%2)*250 - 30;//        int dy = (i/2)*150;//        const Scalar white = Scalar(255);//        const Scalar black = Scalar(0);//        if( i == 0 )//        {//            for( int j = 0; j <= 10; j++ )//            {//                double angle = (j+5)*CV_PI/21;//                line(img, Point(cvRound(dx+100+j*10-80*cos(angle)),//                    cvRound(dy+100-90*sin(angle))),//                    Point(cvRound(dx+100+j*10-30*cos(angle)),//                    cvRound(dy+100-30*sin(angle))), white, 1, 8, 0);//            }//        }//        ellipse( img, Point(dx+150, dy+100), Size(100,70), 0, 0, 360, white, -1, 8, 0 );//        ellipse( img, Point(dx+115, dy+70), Size(30,20), 0, 0, 360, black, -1, 8, 0 );//        ellipse( img, Point(dx+185, dy+70), Size(30,20), 0, 0, 360, black, -1, 8, 0 );//        ellipse( img, Point(dx+115, dy+70), Size(15,15), 0, 0, 360, white, -1, 8, 0 );//        ellipse( img, Point(dx+185, dy+70), Size(15,15), 0, 0, 360, white, -1, 8, 0 );//        ellipse( img, Point(dx+115, dy+70), Size(5,5), 0, 0, 360, black, -1, 8, 0 );//        ellipse( img, Point(dx+185, dy+70), Size(5,5), 0, 0, 360, black, -1, 8, 0 );//        ellipse( img, Point(dx+150, dy+100), Size(10,5), 0, 0, 360, black, -1, 8, 0 );//        ellipse( img, Point(dx+150, dy+150), Size(40,10), 0, 0, 360, black, -1, 8, 0 );//        ellipse( img, Point(dx+27, dy+100), Size(20,35), 0, 0, 360, white, -1, 8, 0 );//        ellipse( img, Point(dx+273, dy+100), Size(20,35), 0, 0, 360, white, -1, 8, 0 );//    }    Mat img = imread("/home/unsw/lolo.jpg");    Mat gray;    cvtColor(img, gray, COLOR_RGB2GRAY );    Mat binary;    threshold(gray, binary, 200,255,THRESH_BINARY);    // (1) Pic One Show: show the faces    namedWindow( "image", 1 );    imshow( "image", binary );    // (2) Pic Two Show    //Extract the contours so that    vector<vector<Point> > contours0;    findContours( binary, contours0, hierarchy, RETR_TREE, CHAIN_APPROX_SIMPLE);    contours.resize(contours0.size());    for( size_t k = 0; k < contours0.size(); k++ )        approxPolyDP(Mat(contours0[k]), contours[k], 3, true);    // Jeff --> the same name to bind window and trackbar together.    //          qt qml to draw would be much better.    //          callback: on_trackbar()    namedWindow( "contours", 1 );    createTrackbar( "levels+3", "contours", &levels, 7, on_trackbar );    on_trackbar(0,0);    waitKey();    return 0;}

 1 static int getContoursByCplus(char* Imgname, double minarea, double whRatio)   2 {   3     cv::Mat src, dst, canny_output;   4     /// Load source image and convert it to gray   5     src = http://www.mamicode.com/imread(Imgname, 0);   6    7     if (!src.data)   8     {   9         std::cout << "read data error!" << std::endl;  10         return -1;  11     }  12     blur(src, src, Size(3, 3));  13   14       15     //the pram. for findContours,  16     vector<vector<Point> > contours;  17     vector<Vec4i> hierarchy;  18   19     /// Detect edges using canny  20     Canny(src, canny_output, 80, 255, 3);  21     /// Find contours  22     findContours(canny_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0));  23     //CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE  24   25     double maxarea = 0;  26     int maxAreaIdx = 0;  27   28     for (int i = 0; i<contours.size(); i++)  29     {  30   31         double tmparea = fabs(contourArea(contours[i]));  32         if (tmparea>maxarea)  33         {  34             maxarea = tmparea;  35             maxAreaIdx = i;  36             continue;  37         }  38           39         if (tmparea < minarea)  40         {  41             // *** 删除面积小于设定值的轮廓  42             contours.erase(contours.begin() + i);   43             std::wcout << "delete a small area" << std::endl;  44             continue;  45         }  46         //计算轮廓的直径宽高  47         Rect aRect =boundingRect(contours[i]);  48         if ((aRect.width / aRect.height)<whRatio)  49         {  50             // *** 删除宽高比例小于设定值的轮廓  51             contours.erase(contours.begin() + i);   52             std::wcout << "delete a unnomalRatio area" << std::endl;  53             continue;  54         }  55     }  56     /// Draw contours,彩色轮廓  57     dst= Mat::zeros(canny_output.size(), CV_8UC3);  58     for (int i = 0; i< contours.size(); i++)  59     {  60         //随机颜色  61         Scalar color = Scalar(rng.uniform(0, 255), rng.uniform(0, 255), rng.uniform(0, 255));  62         drawContours(dst, contours, i, color, 2, 8, hierarchy, 0, Point());  63     }  64     // Create Window  65     char* source_window = "countors";  66     namedWindow(source_window, CV_WINDOW_NORMAL);  67     imshow(source_window, dst);  68     cv:; waitKey(0);  69       70     return 0;  71 }