Added functions for checking luminosity violation

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

@@ -46,6 +46,7 @@ public class MainActivity extends AppCompatActivity {
 
 
         VideoDetector vd = new VideoDetector(this);
+        vd.setPreviewView(previewView);
         vd.startDetection();
 
         previewButton.setOnClickListener(new View.OnClickListener() {

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

@@ -13,6 +13,7 @@ import androidx.camera.core.ImageAnalysis;
 import androidx.camera.core.ImageProxy;
 import androidx.camera.core.Preview;
 import androidx.camera.lifecycle.ProcessCameraProvider;
+import androidx.camera.view.PreviewView;
 import androidx.core.content.ContextCompat;
 import androidx.lifecycle.LifecycleOwner;
 
@@ -23,20 +24,31 @@ import java.util.concurrent.ExecutionException;
 
 @ExperimentalGetImage
 public class VideoDetector {
-
+    // Calling Activity
     private final Context context;
+    // Camera Provider
     private ProcessCameraProvider cameraProvider;
     private Boolean isDetectionRunning = false;
-    //private float currentLuminosity;
+    // Preview Camera Image
+    private PreviewView previewView = null;
+    // Check Violation
+    private final float DELTA_LUMINOSITY_THRESHOLD = 10f;
+    private float lastLuminosity = 0f;
+    private Boolean isViolated = false;
+
 
     /** Constructor */
-    public VideoDetector(Context context) {
-        this.context = context;
-    }
+    public VideoDetector(Context context) { this.context = context; }
+
+
 
     /** Return State of Video Detector */
-    public Boolean isRunning() {
-        return isDetectionRunning;
+    public Boolean isRunning() { return isDetectionRunning; }
+
+    /** Return the status of Violation */
+    public boolean getViolationStatus()
+    {
+        return isViolated;
     }
 
     /** Starts Video Detection */
@@ -64,6 +76,11 @@ public class VideoDetector {
         isDetectionRunning = false;
     }
 
+    /** Set PreviewView to show Image */
+    public void setPreviewView(PreviewView previewView) {
+        this.previewView = previewView;
+    }
+
     /** Binds the Luminosity Analyzer (configure and run Analysis) */
     private void bindLuminosityAnalysis(@NonNull ProcessCameraProvider cameraProvider) {
         // Configure and create Image Analysis
@@ -83,6 +100,9 @@ public class VideoDetector {
                     // Analyze frame
                     float luminosity = calculateLuminosity(image);
                     Log.d("Video Detector", String.valueOf(luminosity));
+                    if (luminosity != 0)
+                        checkForViolation(luminosity, lastLuminosity);
+                    lastLuminosity = luminosity;
                 }
                 imageProxy.close();
             }
@@ -91,7 +111,10 @@ public class VideoDetector {
         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
+        // Update PreviewView if set
+        if (previewView != null)
+            preview.setSurfaceProvider(previewView.getSurfaceProvider());
+
         cameraProvider.bindToLifecycle((LifecycleOwner) context, cameraSelector, imageAnalysis, preview);
     }
 
@@ -118,4 +141,14 @@ public class VideoDetector {
         }
         return sum / (width * height);
     }
+
+    /** Check if delta Luminosity exceeds threshold */
+    private void checkForViolation(float luminosity, float previousLuminosity) {
+        float deltaLuminosity = Math.abs(luminosity - previousLuminosity);
+        if (deltaLuminosity > DELTA_LUMINOSITY_THRESHOLD) {
+            isViolated = true;
+            Log.d("Violation", "Violation");
+        }
+        Log.d("Delta", String.valueOf(Math.abs(previousLuminosity - luminosity)));
+    }
 }