Shift VideoCapture stuff to Input class instead of readWebcam method; Add freeWebcam method

Input/input.cpp

 #include "input.h"
 
-Input::Input(/* args */)
+Input::Input(/* args */) : cap(0)
 {
+    const int VID_HEIGHT = 240;
+    const int VID_WIDTH = 320;
+
+    this->cap.set(CAP_PROP_FRAME_HEIGHT, VID_HEIGHT);
+    this->cap.set(CAP_PROP_FRAME_WIDTH, VID_WIDTH);
 }
 
 Input::~Input()
 {
+    this->freeWebcam();
 }
 
 Mat Input::readFile(String filePath)
 
 Mat Input::readWebcam()
 {
-    const int VID_HEIGHT = 240;
-    const int VID_WIDTH = 320;
     Mat image;
-    VideoCapture cap(0);
-
-    cap.set(CAP_PROP_FRAME_HEIGHT, VID_HEIGHT);
-    cap.set(CAP_PROP_FRAME_WIDTH, VID_WIDTH);
 
     if(!cap.isOpened()) {
         cout << "Fehler";
     cap.read(image);
     
     return image;  
+}
+
+void Input::freeWebcam()
+{
+    this->cap.release();
 }

Input/input.h

 #include <vector>
 #include <string>
 #include <algorithm>
+
 #include <opencv2/opencv.hpp>
+#include <opencv2/core/utils/logger.hpp>
 
 using namespace std;
 using namespace cv;
 class Input
 {
 private:
+    VideoCapture cap;
 
 public:
     Input(/* args */);
     ~Input();
     Mat readFile(String filePath);
     Mat readWebcam();
+    void freeWebcam();
 };