Kamera um neue Detektion ergänzt

Timer zum besseren Alarm Handling ergänzt

app/src/main/java/com/example/greenwatch/sensors/CameraSensor.java

 import android.content.Context;
 import android.graphics.ImageFormat;
 import android.media.Image;
+import android.os.Handler;
 import android.util.Size;
 
 import androidx.camera.core.CameraSelector;
     private final MutableLiveData<Boolean> mVideoAlarmDetected = new MutableLiveData<>();
     private static CameraSensor cameraSensorInstance;
     private boolean videoAlarmDetected;
+    private boolean isMotionDetected;
     private ByteBuffer previousBuffer;
     private int previousWidth;
     private int previousHeight;
+    private final int threshold = 50;
+    private int startX;
+    private int startY;
+    private int endX;
+    private int endY;
+
+    private static final long ALARM_RESET_DELAY = 5000;
+    private Runnable alarmResetRunnable;
+    private final Handler alarmResetHandler = new Handler();
 
     private CameraSensor() {
         videoAlarmDetected = false;
 
                         if (previousHeight != 0) {
                             assert currentImage != null;
-                            videoAlarmDetected = compareFrames(currentImage);
+                            isMotionDetected = compareFrames(currentImage);
                         }
 
                         assert currentImage != null;
 
                         currentImage.close();
 
+                        if (isMotionDetected) {
+
+                            videoAlarmDetected = true;
+
+                            if(alarmResetRunnable != null) {
+                                alarmResetHandler.removeCallbacks(alarmResetRunnable);
+                            }
+
+                            alarmResetRunnable = this::resetAlarmStatus;
+                            alarmResetHandler.postDelayed(alarmResetRunnable, ALARM_RESET_DELAY);
+                        }
+
                         checkAlarmCondition();
 
                     }
     }
 
     private boolean compareFrames(Image currentImage) {
-
-        ByteBuffer currentBuffer = currentImage.getPlanes()[0].getBuffer();
-
+        Image.Plane[] planes = currentImage.getPlanes();
+        ByteBuffer currentBuffer = planes[0].getBuffer();
         int currentWidth = currentImage.getWidth();
         int currentHeight = currentImage.getHeight();
+        int yRowStride = planes[0].getRowStride();
+        int yPixelStride = planes[0].getPixelStride();
 
         if (previousWidth != currentWidth || previousHeight != currentHeight) {
             return false;
         }
 
-        for (int row = 0; row < previousHeight; row++) {
-            for (int col = 0; col < previousWidth; col++) {
+        int blockSize = kleinstesQuadrat(previousHeight, previousWidth) / 8;
+
+        int numBlocksX = currentWidth / blockSize;
+        int numBlocksY = currentHeight / blockSize;
 
-                int previousIndex = row * previousWidth + col;
-                int currentIndex = row * currentWidth + col;
+        for (int blockY = 0; blockY < numBlocksY; blockY++) {
+            for (int blockX = 0; blockX < numBlocksX; blockX++) {
+                startX = blockX * blockSize;
+                startY = blockY * blockSize;
+                endX = startX + blockSize;
+                endY = startY + blockSize;
 
-                int previousPixel = previousBuffer.get(previousIndex) & 0xFF;
-                int currentPixel = currentBuffer.get(currentIndex) & 0xFF;
+                float currentLuminance = berechneMittlereLuminanz(currentBuffer, yRowStride, yPixelStride);
+                float previousLuminance = berechneMittlereLuminanz(previousBuffer, yRowStride, yPixelStride);
 
-                int pixelDifference = Math.abs(previousPixel - currentPixel);
-                int threshold = 120;
+                int pixelDifference = Math.abs((int) previousLuminance - (int) currentLuminance);
 
                 if (pixelDifference > threshold) {
+                    System.out.println(pixelDifference);
                     return true;
                 }
             }
         }
+
         return false;
     }
 
+    private float berechneMittlereLuminanz(ByteBuffer buffer, int rowStride, int pixelStride) {
+        int sumLuminance = 0;
+        int countPixels = 0;
+
+        for (int row = startY; row < endY; row++) {
+            for (int col = startX; col < endX; col++) {
+                int bufferIndex = row * rowStride + col * pixelStride;
+                int currentPixel = buffer.get(bufferIndex) & 0xFF;
+
+                sumLuminance += currentPixel;
+                countPixels++;
+            }
+        }
+
+        return (float) sumLuminance / countPixels;
+    }
+
+    private int kleinstesQuadrat(int height, int width) {
+        if (height == width) {
+            return height;
+        } else if (height > width) {
+            return kleinstesQuadrat(height - width, width);
+        } else {
+            return kleinstesQuadrat(height, width - height);
+        }
+    }
+
+    private void resetAlarmStatus() {
+        videoAlarmDetected = false;
+        alarmResetRunnable = null;
+    }
+
     public void checkAlarmCondition() {
         if (videoAlarmDetected && !mVideoAlarmDetected.getValue()) {
             setMutableLiveDataVideoMovementDetected();