IntelligentCar_p3.cpp

Mat detected_edges, img_mask;
int const max_lowThreshold = 255;
int lowThreshold = 210, ratio = 3, kernel_size = 3;
char* window_name = "Edge Map";
//CannyThreshold: Trackbar callback - Canny thresholds input with a ratio 1:3
void CannyThreshold(int, void*){
  blur(img_mask, detected_edges, Size(3, 3));             //Reduce noise with a kernel 3x3
  Canny(detected_edges, detected_edges, lowThreshold, lowThreshold * ratio, kernel_size);        //Canny detector
  imshow(window_name, detected_edges);                    //Using Canny's output as a mask, and display our result
}

detected_edges.create(img_mask.size(), img_mask.type());  //Create a window
namedWindow(window_name);
createTrackbar("Min Threshold:", window_name, &lowThreshold, max_lowThreshold, CannyThreshold);   // Create a Trackbar for user to enter threshold
CannyThreshold(0, 0);                                     //Show the image