initial commit

samples/cpp/tutorial_code/ImgProc/Threshold_inRange.cpp

@@ -0,0 +1,105 @@
+#include "opencv2/imgproc.hpp"
+#include "opencv2/highgui.hpp"
+#include "opencv2/videoio.hpp"
+#include <iostream>
+
+using namespace cv;
+
+/** Global Variables */
+const int max_value_H = 360/2;
+const int max_value = 255;
+const String window_capture_name = "Video Capture";
+const String window_detection_name = "Object Detection";
+int low_H = 0, low_S = 0, low_V = 0;
+int high_H = max_value_H, high_S = max_value, high_V = max_value;
+
+//! [low]
+static void on_low_H_thresh_trackbar(int, void *)
+{
+    low_H = min(high_H-1, low_H);
+    setTrackbarPos("Low H", window_detection_name, low_H);
+}
+//! [low]
+
+//! [high]
+static void on_high_H_thresh_trackbar(int, void *)
+{
+    high_H = max(high_H, low_H+1);
+    setTrackbarPos("High H", window_detection_name, high_H);
+}
+
+//! [high]
+static void on_low_S_thresh_trackbar(int, void *)
+{
+    low_S = min(high_S-1, low_S);
+    setTrackbarPos("Low S", window_detection_name, low_S);
+}
+
+static void on_high_S_thresh_trackbar(int, void *)
+{
+    high_S = max(high_S, low_S+1);
+    setTrackbarPos("High S", window_detection_name, high_S);
+}
+
+static void on_low_V_thresh_trackbar(int, void *)
+{
+    low_V = min(high_V-1, low_V);
+    setTrackbarPos("Low V", window_detection_name, low_V);
+}
+
+static void on_high_V_thresh_trackbar(int, void *)
+{
+    high_V = max(high_V, low_V+1);
+    setTrackbarPos("High V", window_detection_name, high_V);
+}
+
+int main(int argc, char* argv[])
+{
+    //! [cap]
+    VideoCapture cap(argc > 1 ? atoi(argv[1]) : 0);
+    //! [cap]
+
+    //! [window]
+    namedWindow(window_capture_name);
+    namedWindow(window_detection_name);
+    //! [window]
+
+    //! [trackbar]
+    // Trackbars to set thresholds for HSV values
+    createTrackbar("Low H", window_detection_name, &low_H, max_value_H, on_low_H_thresh_trackbar);
+    createTrackbar("High H", window_detection_name, &high_H, max_value_H, on_high_H_thresh_trackbar);
+    createTrackbar("Low S", window_detection_name, &low_S, max_value, on_low_S_thresh_trackbar);
+    createTrackbar("High S", window_detection_name, &high_S, max_value, on_high_S_thresh_trackbar);
+    createTrackbar("Low V", window_detection_name, &low_V, max_value, on_low_V_thresh_trackbar);
+    createTrackbar("High V", window_detection_name, &high_V, max_value, on_high_V_thresh_trackbar);
+    //! [trackbar]
+
+    Mat frame, frame_HSV, frame_threshold;
+    while (true) {
+        //! [while]
+        cap >> frame;
+        if(frame.empty())
+        {
+            break;
+        }
+
+        // Convert from BGR to HSV colorspace
+        cvtColor(frame, frame_HSV, COLOR_BGR2HSV);
+        // Detect the object based on HSV Range Values
+        inRange(frame_HSV, Scalar(low_H, low_S, low_V), Scalar(high_H, high_S, high_V), frame_threshold);
+        //! [while]
+
+        //! [show]
+        // Show the frames
+        imshow(window_capture_name, frame);
+        imshow(window_detection_name, frame_threshold);
+        //! [show]
+
+        char key = (char) waitKey(30);
+        if (key == 'q' || key == 27)
+        {
+            break;
+        }
+    }
+    return 0;
+}