適当な画像（テンプレート）を適当な範囲で適当な回数検出する

template_matching_for_anytimes_for_anyrange.cc

#include <opencv2/core/core.hpp>
#include <opencv2/opencv.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <vector>

int main(int argc, char** argv) {

  cv::VideoCapture cap(1);
  if(!cap.isOpened()) {
    std::cout << "Camera couldn't open !\n";
    return -1;
  }
  cv::namedWindow("window", 1);
  
  // テンプレートとなる画像
  std::vector<cv::Mat> img;
  img.push_back(cv::imread("./0.png", 1));
  img.push_back(cv::imread("./1.png", 1));
  img.push_back(cv::imread("./3.png", 1));
  img.push_back(cv::imread("./4.png", 1));
  img.push_back(cv::imread("./9.png", 1));
  
  // 適当な範囲 (MacBookAirのカメラは1280x720だった)
  cv::Rect search_range = cv::Rect(0, 600, 500, 100);
  // 適当な回数
  int times_to_detect = 4;
  // 適当な精度
  double detection_accuracy = 0.7;
  
  while(true) {
    cv::Mat frame;
    cap >> frame;
    cv::Mat frame0 = frame(search_range); // ROI
    cv::rectangle(frame, search_range, cv::Scalar(0, 0, 255)); // red

    for(size_t j = 0; j < img.size(); j++) {
      cv::Mat result_img;
      cv::matchTemplate(frame0, img[j], result_img, CV_TM_CCOEFF_NORMED);
      for(int i = 0; i < times_to_detect; i++) {
        cv::Point max_pt;
        double maxVal;
        cv::minMaxLoc(result_img, NULL, &maxVal, NULL, &max_pt);

        if(maxVal < detection_accuracy) break;
        cv::Rect roi_rect(0, 0, img[j].cols, img[j].rows);
        roi_rect.x = max_pt.x + search_range.x;
        roi_rect.y = max_pt.y + search_range.y;
        cv::rectangle(frame, roi_rect, cv::Scalar(0, 255, 255)); // yellow
      }
    }

    cv::imshow("window", frame);

    cv::waitKey(10);
  }
  return 0;
}