OPENCV Screen Tracking

#include <stdio.h>#include<iostream>#include"opencv2/imgproc/imgproc.hpp"#include"opencv2/core/core.hpp"#include"opencv2/features2d/features2d.hpp"#include"opencv2/highgui/highgui.hpp"#include"opencv2/calib3d/calib3d.hpp"#include"opencv2/nonfree/nonfree.hpp"using namespaceCV;intMainintargcChar**argv) {Cvcapture* Capture = Cvcreatefilecapture ("Sign3.mp4" ); Mat Img_object= Imread ("pic3.jpg", Cv_load_image_grayscale); Mat Frame=Cvqueryframe (Capture);    Mat Img_scene;    Cvtcolor (frame, img_scene, Cv_bgr2gray); intMinhessian = -;    Surffeaturedetector detector (Minhessian); Std::vector<KeyPoint>Keypoints_object, Keypoints_scene;    Detector.detect (Img_object, keypoints_object);    Surfdescriptorextractor extractor;    Mat Descriptors_object, Descriptors_scene;    Extractor.compute (Img_object, Keypoints_object, Descriptors_object);    Flannbasedmatcher Matcher; Std::vector< Dmatch >matches; Std::vector<Point2f>obj; Std::vector<Point2f>scene;  while(1) {Frame=Cvqueryframe (Capture);        Cvtcolor (frame, img_scene, Cv_bgr2gray); if(!img_object.data | |!img_scene.data) {Std::cout<<" --(!) Error reading Images"<< Std::endl;return-1; } //--Step 1:detect the keypoints using SURF DetectorDetector.detect (Img_scene, Keypoints_scene); //--Step 2:calculate descriptors (feature vectors)Extractor.compute (Img_scene, Keypoints_scene, Descriptors_scene); //--Step 3:matching descriptor vectors using FLANN matcherMatcher.match (Descriptors_object, descriptors_scene, matches); DoubleMax_dist =0;DoubleMin_dist = -; //--Quick calculation of Max and min distances between keypoints         for(inti =0; i < descriptors_object.rows; i++ )        {             DoubleDist =matches[i].distance; if(Dist <min_dist) Min_dist=Dist; if(Dist >max_dist) Max_dist=Dist; }//printf ("--Max dist:%f \ n", max_dist);//printf ("-Min dist:%f \ n", min_dist); //--Draw only "good" matches (i.e whose distance are less than 3*min_dist)std::vector< Dmatch >good_matches;  for(inti =0; i < descriptors_object.rows; i++ )        {             if(Matches[i].distance <2*min_dist)                 {Good_matches.push_back (matches[i]);        }} Mat img_matches; Drawmatches (Img_object, Keypoints_object, Img_scene, Keypoints_scene, Good_matches, Img_matches, Scalar::all ( /c3>-1), Scalar::all (-1), Vector<Char>(), drawmatchesflags::not_draw_single_points); //--Localize the object                 for(inti =0; I < good_matches.size (); i++ )        {            //--Get The keypoints from the good matchesobj.push_back (keypoints_object[good_matches[i].queryidx].pt);        Scene.push_back (keypoints_scene[good_matches[i].trainidx].pt); } Mat H= Findhomography (obj, Scene, Cv_ransac,5.0 ); //--Get the corners from the Image_1 (the object is "detected")Std::vector<point2f> Obj_corners (4); obj_corners[0] = Cvpoint (0,0); obj_corners[1] = Cvpoint (Img_object.cols,0 ); obj_corners[2] = Cvpoint (Img_object.cols, img_object.rows); obj_corners[3] = Cvpoint (0, img_object.rows); Std::vector<Point2f> Scene_corners (4);        Perspectivetransform (Obj_corners, Scene_corners, H); //--Draw lines between the corners (the mapped object in the scene-image_2)Line (Img_matches, scene_corners[0] + point2f (img_object.cols,0), scene_corners[1] + point2f (img_object.cols,0), Scalar (0,255,0),4 ); Line (img_matches, scene_corners[1] + point2f (img_object.cols,0), scene_corners[2] + point2f (img_object.cols,0), Scalar (0,255,0),4 ); Line (img_matches, scene_corners[2] + point2f (img_object.cols,0), scene_corners[3] + point2f (img_object.cols,0), Scalar (0,255,0),4 ); Line (img_matches, scene_corners[3] + point2f (img_object.cols,0), scene_corners[0] + point2f (img_object.cols,0), Scalar (0,255,0),4 ); //--Show detected matchesNamedwindow ("Good Matches & Object detection", Window_normal); Imshow ("Good Matches & Object detection", img_matches); Charc = Cvwaitkey (1); if(c = = -) Break; }    return 0;}

OPENCV Screen Tracking