added aruco markers detection (not sent to MATLAB yet!)

tello-vision.cpp

 #include "opencv2/opencv.hpp"
+#include "opencv2/aruco.hpp"
 #include <iostream>
 
 #include <stdlib.h> 
@@ -12,8 +13,6 @@
 #define MATLAB_PORT    11112 
 #define MAXLINE        1024 
 
-using namespace cv;
-
 int main(int argc, char** argv) {
 
     int sockfd; 
@@ -34,17 +33,25 @@ int main(int argc, char** argv) {
     cliaddr.sin_addr.s_addr = INADDR_ANY; 
     cliaddr.sin_port = htons(MATLAB_PORT);
 
-    Mat frame;
+    cv::Mat frame;
 
-    VideoCapture cap("udp://127.0.0.1:11111",CAP_FFMPEG);
+    cv::VideoCapture cap("udp://127.0.0.1:11111", cv::CAP_FFMPEG);
 
     cap >> frame; // get a first frame!
 
+    std::vector<int> markerIds;
+    std::vector<std::vector<cv::Point2f>> markerCorners, rejectedCandidates;
+    cv::Ptr<cv::aruco::DetectorParameters> parameters = cv::aruco::DetectorParameters::create();
+    cv::Ptr<cv::aruco::Dictionary> dictionary = cv::aruco::getPredefinedDictionary(cv::aruco::DICT_4X4_100);
+
     for(;;) {
 
         cap >> frame;
 
-        imshow("tello vision", frame);
+        cv::aruco::detectMarkers(frame, dictionary, markerCorners, markerIds, parameters, rejectedCandidates);
+        cv::aruco::drawDetectedMarkers(frame, markerCorners, markerIds);
+
+        cv::imshow("tello vision", frame);
 
         sendto(sockfd, (const char *)hello, strlen(hello),  
             0, (const struct sockaddr *) &cliaddr, 
@@ -52,7 +59,7 @@ int main(int argc, char** argv) {
 
         if ( frame.empty() ) break; // end of video stream
 
-        if( waitKey(10) == 27 ) break; // stop capturing by pressing ESC
+        if( cv::waitKey(10) == 27 ) break; // stop capturing by pressing ESC
 
     }