Fixed a bug in the video decoder

app/src/main/java/com/example/ueberwachungssystem/MainActivity.java

         vd.setOnDetectionListener(new VideoDetector.OnDetectionListener() {
             @Override
             public void onDetection(DetectionReport detectionReport) {
-                Log.d("Listener", detectionReport.detectionType);
+                detectionReport.log("OnDetection");
             }
         });
         vd.startDetection();
             }
         }
     }
-
-
-    private void previewCamera() {
-        // Request Camera Access
-        getCameraAccess();
-        // Return when Camera Access not allowed or Camera Preview is running
-        if (!isCameraAccessAllowed() || cameraPreviewIsRunning)
-            return;
-        // Camera Preview is running
-        cameraPreviewIsRunning = true;
-        // Request Camera Provider
-        final ListenableFuture<ProcessCameraProvider> cameraProviderFuture = ProcessCameraProvider.getInstance(this);
-        //Check for Camera availability
-        cameraProviderFuture.addListener(new Runnable() {
-                @Override
-                public void run() {
-                    try {
-                        ProcessCameraProvider cameraProvider = cameraProviderFuture.get();
-                        bindPreview(cameraProvider);
-                    } catch (ExecutionException | InterruptedException e) {
-                        // No errors need to be handled for this Future. This should never be reached.
-                    }
-                }
-            },ContextCompat.getMainExecutor(this));
-    }
-
-    private void bindPreview(@NonNull ProcessCameraProvider cameraProvider) {
-        // Create Preview
-        Preview preview = new Preview.Builder().build();
-        // Specify which Camera to use
-        CameraSelector cameraSelector = new CameraSelector.Builder().requireLensFacing(CameraSelector.LENS_FACING_BACK).build();
-        // Connect Preview to PreviewView
-        preview.setSurfaceProvider(previewView.getSurfaceProvider());
-        Camera camera = cameraProvider.bindToLifecycle((LifecycleOwner)this, cameraSelector, preview);
-    }
 }

app/src/main/java/com/example/ueberwachungssystem/VideoDetection/VideoDetector.java

 
 @ExperimentalGetImage
 public class VideoDetector {
+
     // Calling Activity
     private final Context context;
     // Camera Provider
 
 
     /** Constructor */
-    public VideoDetector(Context context) { this.context = context; }
+    public VideoDetector(Context context) {
+        this.context = context;
+    }
 
 
     /** On Detection Listener - runs when a violation is reported */
     public interface OnDetectionListener {
-        public void onDetection(DetectionReport detectionReport);
+        void onDetection(DetectionReport detectionReport);
     }
     public void setOnDetectionListener(OnDetectionListener listener) {
         this.listener = listener;
     }
     public void reportViolation(float amplitude) {
-        DetectionReport detectionReport = new DetectionReport("123", "Video", amplitude);
-        if (listener != null)
+        if (listener != null) {
+            DetectionReport detectionReport = new DetectionReport("123", "Video", amplitude);
             listener.onDetection(detectionReport);
+        }
     }
 
 
 
     /** Starts Video Detection */
     public void startDetection() {
-        isDetectionRunning = true;
+        if (isDetectionRunning)
+            return;
         // Request Camera Provider
         final ListenableFuture<ProcessCameraProvider> cameraProviderFuture = ProcessCameraProvider.getInstance(context);
         //Check for Camera availability
                 try {
                     cameraProvider = cameraProviderFuture.get();
                     bindLuminosityAnalysis(cameraProvider);
+                    isDetectionRunning = true;
                 } catch (ExecutionException | InterruptedException e) {
                     // No errors need to be handled for this Future. This should never be reached.
                 }
 
     /** Stops Video Detection */
     public void stopDetection() {
+        if (!isDetectionRunning)
+            return;
         cameraProvider.unbindAll();
         isDetectionRunning = false;
     }