Dopasowane szablonu Imge (skalowane) do Głównego/powiększ

Question

Chcę znaleźć/sprawdzić subImage/szablon zdjęcie w głównym obrazu i chcą wiedzieć, jego współrzędne,

Mam kod podany na poniższy link w celu jej wdrożenia używany,

Check presence of subimage in image in iOS

to działa dobrze, jeśli wielkość matrycy obraz jest dokładnie taki sam jak rozmiar części pasującej do większego obrazu.

Nie daje to jednak prawidłowego wyniku, jeśli obraz dolny zostanie zmniejszony lub zmniejszony w stosunku do pasującego fragmentu większego obrazu.

Answer 1

Użyj funkcji wykrywania OpenCV. to jest bardziej dokładne niż dopasowanie szablonu ..

Spróbuj z tym kodem ..

-(void)featureDetection:(UIImage*)largerImage withImage:(UIImage*)subImage 
{ 
    cv::Mat tempMat1 = [largerImage CVMat]; 
    cv::Mat tempMat2 = [subImage CVMat]; 

    cv::cvtColor(tempMat1, tempMat1, CV_RGB2GRAY); 
    cv::cvtColor(tempMat2, tempMat2, CV_RGB2GRAY); 

    if(!tempMat1.data || !tempMat2.data) { 
     return; 
    } 

    //-- Step 1: Detect the keypoints using SURF Detector 
    int minHessian = 25; 

    cv::SurfFeatureDetector detector(minHessian); // More Accurate bt take more time.. 
    //cv::FastFeatureDetector detector(minHessian); //Less Accurate bt take less time.. 

    std::vector<cv::KeyPoint> keypoints_1, keypoints_2; 

    detector.detect(tempMat1, keypoints_1); 
    detector.detect(tempMat2, keypoints_2); 

    //-- Step 2: Calculate descriptors (feature vectors) 
    cv::SurfDescriptorExtractor extractor; 

    cv::Mat descriptors_1, descriptors_2; 

    extractor.compute(tempMat1, keypoints_1, descriptors_1); 
    extractor.compute(tempMat2, keypoints_2, descriptors_2); 

    std::vector<cv::Point2f> obj_corners(4); 

    //Get the corners from the object 
    obj_corners[0] = (cvPoint(0,0)); 
    obj_corners[1] = (cvPoint(tempMat2.cols,0)); 
    obj_corners[2] = (cvPoint(tempMat2.cols,tempMat2.rows)); 
    obj_corners[3] = (cvPoint(0, tempMat2.rows)); 

    //-- Step 3: Matching descriptor vectors with a brute force matcher 
    //cv::BruteForceMatcher < cv::L2<float> > matcher; 
    cv::FlannBasedMatcher matcher; 
    //std::vector<cv::DMatch> matches; 
    std::vector<cv::vector<cv::DMatch > > matches; 

    std::vector<cv::DMatch > good_matches; 
    std::vector<cv::Point2f> obj; 
    std::vector<cv::Point2f> scene; 
    std::vector<cv::Point2f> scene_corners(4); 
    cv::Mat H; 

    matcher.knnMatch(descriptors_2, descriptors_1, matches,2); 

    for(int i = 0; i < cv::min(tempMat1.rows-1,(int) matches.size()); i++) { 

     if((matches[i][0].distance < 0.6*(matches[i][1].distance)) && ((int) matches[i].size()<=2 && (int) matches[i].size()>0)) { 
      good_matches.push_back(matches[i][0]); 
     } 
    } 
    cv::Mat img_matches; 
    drawMatches(tempMat2, keypoints_2, tempMat1, keypoints_1, good_matches, img_matches); 

    NSLog(@"good matches %lu",good_matches.size()); 

    if (good_matches.size() >= 4) { 

     for(int i = 0; i < good_matches.size(); i++) { 
      //Get the keypoints from the good matches 
      obj.push_back(keypoints_2[ good_matches[i].queryIdx ].pt); 
      scene.push_back(keypoints_1[ good_matches[i].trainIdx ].pt); 
     } 

     H = findHomography(obj, scene, CV_RANSAC); 

     perspectiveTransform(obj_corners, scene_corners, H); 

     NSLog(@"%f %f",scene_corners[0].x,scene_corners[0].y); 
     NSLog(@"%f %f",scene_corners[1].x,scene_corners[1].y); 
     NSLog(@"%f %f",scene_corners[2].x,scene_corners[2].y); 
     NSLog(@"%f %f",scene_corners[3].x,scene_corners[3].y); 


     //Draw lines between the corners (the mapped object in the scene image) 
     line(tempMat1, scene_corners[0], scene_corners[1], cvScalar(0, 255, 0), 4); 

     line(tempMat1, scene_corners[1], scene_corners[2], cvScalar(0, 255, 0), 4); 

     line(tempMat1, scene_corners[2], scene_corners[3], cvScalar(0, 255, 0), 4); 

     line(tempMat1, scene_corners[3], scene_corners[0], cvScalar(0, 255, 0), 4); 
    } 

    // View matching.. 

    UIImage *resultimage = [UIImage imageWithCVMat:img_matches]; 
    UIImageView *imageview = [[UIImageView alloc] initWithImage:resultimage]; 
    imageview.frame = CGRectMake(0, 0, 320, 240); 
    [self.view addSubview:imageview]; 

    // View Result 

    UIImage *resultimage2 = [UIImage imageWithCVMat:tempMat1]; 
    UIImageView *imageview2 = [[UIImageView alloc] initWithImage:resultimage2]; 
    imageview2.frame = CGRectMake(0, 240, 320, 240); 
    [self.view addSubview:imageview2]; 
}