1 #include "opencv2/highgui/highgui.hpp" 2 #include "opencv2/imgproc/imgproc.hpp" 3 4 #include <iostream> 5 6 using namespace cv; 7 using namespace std; 8 9 static void help() 10 { 11 cout << "This program demonstrates finding the minimum enclosing box, triangle or circle of a set\n" 12 << "of points using functions: minAreaRect() minEnclosingTriangle() minEnclosingCircle().\n" 13 << "Random points are generated and then enclosed.\n\n" 14 << "Press ESC, 'q' or 'Q' to exit and any other key to regenerate the set of points.\n\n" 15 << "Call:\n" 16 << "./minarea\n" 17 << "Using OpenCV v" << CV_VERSION << "\n" << endl; 18 } 19 20 int main( int /*argc*/, char** /*argv*/ ) 21 { 22 help(); 23 24 Mat img(500, 500, CV_8UC3); 25 RNG& rng = theRNG(); 26 27 for(;;) 28 { 29 int i, count = rng.uniform(1, 101); 30 vector<Point> points; 31 32 // Generate a random set of points 33 for( i = 0; i < count; i++ ) 34 { 35 Point pt; 36 pt.x = rng.uniform(img.cols/4, img.cols*3/4); 37 pt.y = rng.uniform(img.rows/4, img.rows*3/4); 38 39 points.push_back(pt); 40 } 41 42 // Find the minimum area enclosing bounding box 43 RotatedRect box = minAreaRect(Mat(points)); 44 45 // Find the minimum area enclosing triangle 46 vector<Point2f> triangle; 47 48 minEnclosingTriangle(points, triangle); 49 50 // Find the minimum area enclosing circle 51 Point2f center, vtx[4]; 52 float radius = 0; 53 minEnclosingCircle(Mat(points), center, radius); 54 box.points(vtx); 55 56 img = Scalar::all(0); 57 58 // Draw the points 59 for( i = 0; i < count; i++ ) 60 circle( img, points[i], 3, Scalar(0, 0, 255), FILLED, LINE_AA ); 61 62 // Draw the bounding box 63 for( i = 0; i < 4; i++ ) 64 line(img, vtx[i], vtx[(i+1)%4], Scalar(0, 255, 0), 1, LINE_AA); 65 66 // Draw the triangle 67 for( i = 0; i < 3; i++ ) 68 line(img, triangle[i], triangle[(i+1)%3], Scalar(255, 255, 0), 1, LINE_AA); 69 70 // Draw the circle 71 circle(img, center, cvRound(radius), Scalar(0, 255, 255), 1, LINE_AA); 72 73 imshow( "Rectangle, triangle & circle", img ); 74 75 char key = (char)waitKey(); 76 if( key == 27 || key == 'q' || key == 'Q' ) // 'ESC' 77 break; 78 } 79 80 return 0; 81 } 82
