Refactor

startDetection(), stopDetection(), isRunning()

Notiz.txt

@@ -1,3 +0,0 @@
-Sensor als Service einrichten, der aus Activity heraus gestartet werden kann.
-Stichwort: Intent
-Siehe Skript Teil 1

app/build.gradle

@@ -36,4 +36,13 @@ dependencies {
     testImplementation 'junit:junit:4.13.2'
     androidTestImplementation 'androidx.test.ext:junit:1.1.5'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
+
+    // Required for CameraX
+    def camerax_version = "1.2.2"
+    implementation "androidx.camera:camera-core:${camerax_version}"
+    implementation "androidx.camera:camera-camera2:${camerax_version}"
+    implementation "androidx.camera:camera-lifecycle:${camerax_version}"
+    implementation "androidx.camera:camera-video:${camerax_version}"
+    implementation "androidx.camera:camera-view:${camerax_version}"
+    implementation "androidx.camera:camera-extensions:${camerax_version}"
 }

app/src/main/AndroidManifest.xml

@@ -2,6 +2,9 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools">
 
+    <uses-feature android:name="android.hardware.camera"/>
+    <uses-permission android:name="android.permission.CAMERA"/>
+
     <application
         android:allowBackup="true"
         android:dataExtractionRules="@xml/data_extraction_rules"

app/src/main/java/com/example/ueberwachungssystem/Detection/Accelerometer.java

@@ -1,109 +0,0 @@
-package com.example.ueberwachungssystem.Detection;
-
-import static java.lang.Math.sqrt;
-
-import android.content.Context;
-import android.hardware.Sensor;
-import android.hardware.SensorEvent;
-import android.hardware.SensorEventListener;
-import android.hardware.SensorManager;
-
-
-/**
- * Accelerometer inherits some methods from abstract Detector class (more info there)
- *
- *
- * USE FROM MAIN ACTIVITY:
- *
- * Accelerometer beschleunigungssensor = new Accelerometer(this);
- * onCreate:
- * //Accelerometer Setup
- * beschleunigungssensor = new Accelerometer(this, logger, textViewLog);   //logger and textview only for debugging necessary
- * beschleunigungssensor.getSensor();
- *
- * //Starting Detection:
- * beschleunigungssensor.startDetection();
- * //Stopping Detection: also recommended at onPause to avoid unnecessary battery consumption
- * beschleunigungssensor.stopDetection();
- *
- * */
-
-public class Accelerometer extends Detector implements SensorEventListener {
-
-    public SensorManager sensorManager;
-    private static final int sensorType = Sensor.TYPE_LINEAR_ACCELERATION;
-    private Sensor accelerometer;
-    private Context context;
-    boolean alarm = false;
-    //Preallocate memory for the data of each axis of the acceleration sensor
-    float x;
-    float y;
-    float z;
-    float betrag; //Betrag aller drei Achsen sqrt(x*x + y*y + z*z)
-    private DetectionReport detectionReport;
-
-    // In constructor pass Activity, Context and TextView from MainActivity in Accelerometer class
-    public Accelerometer(Context context){
-        super(context); //von Detektor
-        this.context = context;
-    }
-
-    public void getSensor(){
-        sensorManager = (SensorManager)context.getSystemService(Context.SENSOR_SERVICE);
-        if(sensorManager.getSensorList(sensorType).size()==0) {
-            accelerometer = null;
-        }
-        else {
-            accelerometer = sensorManager.getSensorList(sensorType).get(0);
-        }
-    }
-
-    @Override
-    public void onSensorChanged(SensorEvent event) {
-        try {
-            checkAlarm(event);
-        } catch (InterruptedException e) {
-            throw new RuntimeException(e);
-        }
-    }
-
-    public void checkAlarm (SensorEvent event) throws InterruptedException {
-        x = event.values[0];
-        y = event.values[1];
-        z = event.values[2];
-        betrag = (float) sqrt(x*x + y*y + z*z);
-        float threshold = 1.5F;
-
-        if (!alarm) {
-            if (betrag > threshold) {
-                alarm = true;
-                detectionReport = new DetectionReport("Accelerometer1", "Bewegung", betrag);
-                reportViolation("Accelo1", "Bewegung", betrag);
-            }
-        } else {
-            if (betrag < threshold) {
-                alarm = false;
-            } else {
-            }
-        }
-    }
-
-    @Override
-    public void onAccuracyChanged(Sensor sensor, int accuracy) {
-    }
-
-    @Override
-    public void startDetection() {
-        // entspricht void start()
-        //getSensor();
-        if (accelerometer != null) {
-            sensorManager.registerListener(this, accelerometer, SensorManager.SENSOR_DELAY_GAME);
-        }
-    }
-
-    @Override
-    public void stopDetection() {
-        // entspricht void stop()
-        sensorManager.unregisterListener(this, accelerometer);
-    }
-}

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

@@ -1,4 +1,4 @@
-package com.example.ueberwachungssystem.Detection;
+package com.example.ueberwachungssystem;
 
 import android.util.Log;
 

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

@@ -1,6 +1,5 @@
-package com.example.ueberwachungssystem.Detection;
+package com.example.ueberwachungssystem;
 
-import android.content.Context;
 import androidx.annotation.NonNull;
 
 
@@ -8,7 +7,7 @@ abstract public class Detector {
     private OnDetectionListener listener;
 
     /** Constructor - takes context of current activity */
-    public Detector(Context context) {};
+    public Detector() {}
 
 
     /** On Detection Listener - runs when violation is reported */

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

@@ -2,71 +2,85 @@ package com.example.ueberwachungssystem;
 
 import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
+import androidx.camera.view.PreviewView;
+import androidx.core.app.ActivityCompat;
+import androidx.core.content.ContextCompat;
+import androidx.camera.core.ExperimentalGetImage;
 
+import android.Manifest;
+import android.content.pm.PackageManager;
 import android.os.Bundle;
-import android.text.method.ScrollingMovementMethod;
 import android.view.View;
-import android.widget.Button;
 import android.widget.TextView;
+import android.widget.Toast;
 import android.widget.ToggleButton;
 
-import com.example.ueberwachungssystem.Detection.Accelerometer;
+import com.example.ueberwachungssystem.VideoDetection.VideoDetector;
-import com.example.ueberwachungssystem.Detection.DetectionReport;
-import com.example.ueberwachungssystem.Detection.Detector;
 
-public class MainActivity extends AppCompatActivity implements View.OnClickListener {
+@ExperimentalGetImage
+public class MainActivity extends AppCompatActivity {
+
+    private static final int CAMERA_PERMISSION_REQUEST_CODE = 101;
 
-    private Accelerometer beschleunigungssensor;
-    private TextView textViewLog;
-    private Button button1;
-    ToggleButton toggleButton1;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        setTitle(this.getClass().getSimpleName());
         setContentView(R.layout.activity_main);
 
+        TextView textView = findViewById(R.id.textView);
+        PreviewView previewView = findViewById(R.id.previewView);
 
-        toggleButton1 = findViewById(R.id.toggleButton1); //togglebutton um Detektion zu steuern
-        toggleButton1.setOnClickListener(this);
 
-        //Button to clear Log while Debugging
+        VideoDetector vd = new VideoDetector(this);
-        button1 = (Button) findViewById(R.id.button1);
+        vd.setPreviewView(previewView);
-        button1.setOnClickListener(this);
+        vd.setOnDetectionListener(new VideoDetector.OnDetectionListener() {
-
-        //Accelerometer Setup
-        beschleunigungssensor = new Accelerometer(this);   //logger and textview only for debugging necessary
-        beschleunigungssensor.getSensor();
-        beschleunigungssensor.setOnDetectionListener(new Detector.OnDetectionListener() {
             @Override
             public void onDetection(@NonNull DetectionReport detectionReport) {
-
+                detectionReport.log("OnDetection");
+                textView.setText(detectionReport.toString());
             }
         });
+        //vd.startDetection();
 
-    }
 
-    @Override
+        ToggleButton toggleButton = findViewById(R.id.previewButton);
-    protected void onResume() {
+        toggleButton.setOnClickListener(new View.OnClickListener() {
-        super.onResume();
+            @Override
+            public void onClick(View v) {
+                getCameraAccess();
+                if (isCameraAccessAllowed() && toggleButton.isChecked())
+                {
+                    vd.startDetection();
+                }
+                else {
+                    vd.stopDetection();
+                    textView.setText("");
+                }
+            }
+        });
+    }
+
+    private boolean isCameraAccessAllowed() {
+        return ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED;
     }
-    @Override
+
-    protected void onPause() {
+    private void getCameraAccess() {
-        super.onPause();
+        if (!isCameraAccessAllowed())
-        beschleunigungssensor.stopDetection();
+            ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.CAMERA}, CAMERA_PERMISSION_REQUEST_CODE);
     }
 
     @Override
-    public void onClick(View v) {
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
-        if(v == toggleButton1) {
+        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
-            if (toggleButton1.isChecked()) {
-                beschleunigungssensor.startDetection();
 
+        if (requestCode == CAMERA_PERMISSION_REQUEST_CODE && grantResults.length > 0) {
+            boolean cameraRights = grantResults[0] == PackageManager.PERMISSION_GRANTED;
+            if (cameraRights) {
+                Toast.makeText(this, "camera permission granted", Toast.LENGTH_LONG).show();
             } else {
-                beschleunigungssensor.stopDetection();
+                Toast.makeText(this, "camera permission denied", Toast.LENGTH_LONG).show();
             }
-        } else if (v == button1) {
         }
     }
 }

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

@@ -0,0 +1,165 @@
+package com.example.ueberwachungssystem.VideoDetection;
+
+import android.content.Context;
+import android.graphics.ImageFormat;
+import android.media.Image;
+import android.util.Size;
+
+import androidx.annotation.NonNull;
+import androidx.camera.core.CameraSelector;
+import androidx.camera.core.ExperimentalGetImage;
+import androidx.camera.core.ImageAnalysis;
+import androidx.camera.core.Preview;
+import androidx.camera.lifecycle.ProcessCameraProvider;
+import androidx.camera.view.PreviewView;
+import androidx.core.content.ContextCompat;
+import androidx.lifecycle.LifecycleOwner;
+
+import com.example.ueberwachungssystem.Detector;
+import com.google.common.util.concurrent.ListenableFuture;
+
+import java.nio.ByteBuffer;
+import java.util.concurrent.ExecutionException;
+
+@ExperimentalGetImage
+public class VideoDetector extends Detector {
+
+    // Calling Activity
+    private final Context context;
+    // Camera Provider
+    private ProcessCameraProvider cameraProvider;
+    private Boolean isDetectionRunning = false;
+    // Preview Camera Image
+    private PreviewView previewView = null;
+    // Detect Violation
+    private static final float PIXEL_THRESHOLD = 30f;  // Luminosity (brightness channel of YUV_420_888)
+    private static final float ALARM_THRESHOLD = 1f;   // Percent of pixels changed
+    private ByteBuffer previousBuffer = null;
+
+
+
+    /** Constructor */
+    public VideoDetector(Context context) {
+        super();
+        this.context = context;
+    }
+
+
+    /** Starts Video Detection */
+    @Override
+    public void startDetection() {
+        if (isDetectionRunning)
+            return;
+        // Request Camera Provider
+        final ListenableFuture<ProcessCameraProvider> cameraProviderFuture = ProcessCameraProvider.getInstance(context);
+        //Check for Camera availability
+        cameraProviderFuture.addListener(() -> {
+            try {
+                cameraProvider = cameraProviderFuture.get();
+                bindLuminosityAnalysis(cameraProvider);
+                isDetectionRunning = true;
+                previousBuffer = null;
+            } catch (ExecutionException | InterruptedException e) {
+                // No errors need to be handled for this Future. This should never be reached.
+            }
+        },ContextCompat.getMainExecutor(context));
+    }
+
+
+    /** Stops Video Detection */
+    @Override
+    public void stopDetection() {
+        if (!isDetectionRunning)
+            return;
+        cameraProvider.unbindAll();
+        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
+        ImageAnalysis.Builder builder = new ImageAnalysis.Builder();
+        builder.setTargetResolution(new Size(640, 480));
+        builder.setBackpressureStrategy(ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST);
+        builder.setOutputImageFormat(ImageAnalysis.OUTPUT_IMAGE_FORMAT_YUV_420_888);
+        ImageAnalysis imageAnalysis = builder.build();
+
+        // Set Analyzer
+        imageAnalysis.setAnalyzer(ContextCompat.getMainExecutor(context), imageProxy -> {
+            if (imageProxy.getFormat() == ImageFormat.YUV_420_888) {
+                Image image = imageProxy.getImage();
+                assert image != null;
+
+                // Changed Pixel Detection
+                int pixelChanged = getChangedPixelCount(image);
+                int width = image.getWidth();
+                int height = image.getHeight();
+
+                float percentPixelChanged = (float) 100f * pixelChanged / (width * height);
+
+                if (percentPixelChanged > ALARM_THRESHOLD)
+                    reportViolation("0", "Video", percentPixelChanged);
+            }
+            imageProxy.close();
+        });
+        // Create Preview
+        Preview preview = new Preview.Builder().build();
+        // Specify which Camera to use
+        CameraSelector cameraSelector = new CameraSelector.Builder().requireLensFacing(CameraSelector.LENS_FACING_BACK).build();
+        // Update PreviewView if set
+        if (previewView != null)
+            preview.setSurfaceProvider(previewView.getSurfaceProvider());
+
+        cameraProvider.bindToLifecycle((LifecycleOwner) context, cameraSelector, imageAnalysis, preview);
+    }
+
+
+
+    /** Calculate Amount of Pixels changed */
+    private int getChangedPixelCount(Image image) {
+        Image.Plane[] planes = image.getPlanes();
+        ByteBuffer buffer = planes[0].getBuffer();
+
+        if (previousBuffer == null) {
+            previousBuffer = ByteBuffer.allocate(buffer.capacity());
+            buffer.rewind();
+            previousBuffer.put(buffer);
+            previousBuffer.rewind();
+            return 0;
+        }
+
+        int width = image.getWidth();
+        int height = image.getHeight();
+
+        int yRowStride = image.getPlanes()[0].getRowStride();
+        int yPixelStride = image.getPlanes()[0].getPixelStride();
+
+        int changedPixelCount = 0;
+
+        // Count changed pixels
+        for (int y = 0; y < height; ++y) {
+            for (int x = 0; x < width; x++) {
+                int index = (y * yRowStride) + (x * yPixelStride);
+                int luminosity = (buffer.get(index) & 0xff);
+                int previousLuminosity = (previousBuffer.get(index) & 0xff);
+                int diff = Math.abs(luminosity - previousLuminosity);
+                if (diff > PIXEL_THRESHOLD)
+                    changedPixelCount++;
+            }
+        }
+
+        // Reset and copy Byte Buffer
+        buffer.rewind();
+        previousBuffer.rewind();
+        previousBuffer.put(buffer);
+
+        return changedPixelCount;
+    }
+}

app/src/main/res/layout/activity_main.xml

@@ -1,63 +1,37 @@
 <?xml version="1.0" encoding="utf-8"?>
-<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
+    android:layout_gravity="center"
+    android:gravity="center"
+    android:orientation="vertical"
     tools:context=".MainActivity">
 
     <TextView
-        android:id="@+id/textViewLog"
+        android:id="@+id/textView"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_marginStart="32dp"
+        android:text=""
-        android:layout_marginTop="60dp"
+        android:textSize="20dp"
-        android:layout_marginEnd="32dp"
-        android:maxLines="25"
-        android:scrollbars="vertical"
-        android:text="TextViewLoggerMain"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toBottomOf="@+id/textViewWorkerThread"
+        app:layout_constraintTop_toTopOf="parent" />
-        app:layout_constraintVertical_bias="0.0" />
+
 
     <ToggleButton
-        android:id="@+id/toggleButton1"
+        android:id="@+id/previewButton"
-        android:layout_width="wrap_content"
+        android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:layout_marginStart="161dp"
+        android:text="ToggleButton" />
-        android:layout_marginTop="115dp"
-        android:layout_marginEnd="162dp"
-        android:text="ToggleButton"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent" />
 
-    <TextView
-        android:id="@+id/textViewWorkerThread"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:layout_marginStart="32dp"
-        android:layout_marginTop="16dp"
-        android:layout_marginEnd="32dp"
-        android:text="textViewWorkerThreadTextView"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toBottomOf="@+id/toggleButton1" />
 
-    <Button
+    <androidx.camera.view.PreviewView
-        android:id="@+id/button1"
+        android:id="@+id/previewView"
-        android:layout_width="wrap_content"
+        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
+        android:layout_height="match_parent"
-        android:layout_marginStart="35dp"
+        android:backgroundTint="@android:color/black"/>
-        android:layout_marginTop="31dp"
-        android:layout_marginEnd="282dp"
-        android:layout_marginBottom="100dp"
-        android:text="Clear Log"
-        app:layout_constraintBottom_toTopOf="@+id/textViewWorkerThread"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent" />
 
-</androidx.constraintlayout.widget.ConstraintLayout>
+</LinearLayout>

build.gradle

@@ -1,5 +1,5 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 plugins {
-    id 'com.android.application' version '8.0.0' apply false
+    id 'com.android.application' version '7.4.2' apply false
-    id 'com.android.library' version '8.0.0' apply false
+    id 'com.android.library' version '7.4.2' apply false
 }

gradle.properties

@@ -19,5 +19,3 @@ android.useAndroidX=true
 # resources declared in the library itself and none from the library's dependencies,
 # thereby reducing the size of the R class for that library
 android.nonTransitiveRClass=true
-android.defaults.buildfeatures.buildconfig=true
-android.nonFinalResIds=false

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 #Thu May 11 15:04:30 CEST 2023
 distributionBase=GRADLE_USER_HOME
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.0-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.5-bin.zip
 distributionPath=wrapper/dists
 zipStorePath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME