Merge remote-tracking branch 'origin/bk_video' into bk_video

startDetection(), stopDetection(), isRunning()

app/build.gradle

@@ -36,5 +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'
-    implementation 'com.jjoe64:graphview:4.2.2'
+
+    // 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

@@ -2,12 +2,11 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools">
 
-    <uses-permission android:name="android.permission.RECORD_AUDIO"/>
+    <uses-feature android:name="android.hardware.camera"/>
-    <uses-permission android:name="android.permission.CAMERA"/>
+    <uses-permission android:name="android.permission.CAMERA" />
-    <!--<uses-permission android:name="android.permission.BLUETOOTH"/>-->
+    <uses-permission android:name="android.permission.RECORD_AUDIO" />
-    <!--<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>-->
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
-    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
+    <uses-feature android:name="android.hardware.Camera"/>
-    <uses-permission android:name="android.permission.INTERNET" />
 
     <application
         android:allowBackup="true"

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

@@ -1,4 +1,4 @@
-package com.example.ueberwachungssystem.Detector;
+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.Detector;
+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/Detector/MicrophoneDetector.java

@@ -1,421 +0,0 @@
-package com.example.ueberwachungssystem.Detector;
-
-import static java.lang.Math.*;
-
-import android.Manifest;
-import android.app.Activity;
-import android.content.Context;
-import android.content.pm.PackageManager;
-import android.media.AudioFormat;
-import android.media.AudioRecord;
-import android.media.MediaRecorder;
-import android.os.AsyncTask;
-import android.util.Log;
-
-import androidx.core.app.ActivityCompat;
-import androidx.core.content.ContextCompat;
-
-import com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex;
-import com.example.ueberwachungssystem.Detector.Signalverarbeitung.FFT;
-import com.example.ueberwachungssystem.Detector.logger.Logger;
-import com.jjoe64.graphview.GraphView;
-import com.jjoe64.graphview.series.DataPoint;
-import com.jjoe64.graphview.series.LineGraphSeries;
-
-public class MicrophoneDetector extends Detector {
-    /**
-     * Constructor - takes context of current activity
-     *
-     * @param context
-     */
-
-    private static final int RECHTEANFORDERUNG_MIKROFON = 1;
-
-    private AufnahmeTask aufnahmeTask;
-    public boolean armed = false;
-    public int Schwellwert_Alarm = 100;
-    private Activity MainActivityForClass;
-
-    public MicrophoneDetector(Context context) {
-        super(context);
-        MainActivityForClass = (Activity) context;
-
-        if (!istZugriffAufMikrofonErlaubt()) {
-            zugriffAufMikrofonAnfordern();
-        }
-    }
-
-    @Override
-    public void startDetection() {
-
-        if (!istZugriffAufMikrofonErlaubt()) {
-            zugriffAufMikrofonAnfordern();
-        }
-        if (istZugriffAufMikrofonErlaubt()) {
-            aufnahmeTask = new AufnahmeTask();
-            aufnahmeTask.execute();
-        }
-    }
-
-    @Override
-    public void stopDetection() {
-        if (aufnahmeTask != null) {
-            aufnahmeTask.cancel(true);
-        }
-    }
-
-    private boolean istZugriffAufMikrofonErlaubt() {
-        if (ContextCompat.checkSelfPermission(MainActivityForClass, android.Manifest.permission.RECORD_AUDIO) != PackageManager.PERMISSION_GRANTED) {
-            Log.d("0","Zugriff auf Mikrofon ist verboten.");
-            return false;
-        } else {
-            Log.d("0","Zugriff auf Mikrofon ist erlaubt.");
-            return true;
-        }
-    }
-
-    private void zugriffAufMikrofonAnfordern() {
-        ActivityCompat.requestPermissions(MainActivityForClass, new String[]{Manifest.permission.RECORD_AUDIO}, RECHTEANFORDERUNG_MIKROFON);
-    }
-
-    class AufnahmeTask extends AsyncTask<Long, Verarbeitungsergebnis, Void> {
-        private AudioRecord recorder;
-        private final int sampleRateInHz = 44100;
-        private final int channelConfig = AudioFormat.CHANNEL_IN_MONO;
-        private final int audioFormat = AudioFormat.ENCODING_PCM_16BIT;
-        private int minPufferGroesseInBytes;
-        private int pufferGroesseInBytes;
-        private RingPuffer ringPuffer = new RingPuffer(10);
-        private float kalibierWert;
-        private DetectionReport detectionReport;
-
-        AufnahmeTask() {
-            minPufferGroesseInBytes = AudioRecord.getMinBufferSize(sampleRateInHz, channelConfig, audioFormat);
-            pufferGroesseInBytes = minPufferGroesseInBytes * 2;
-            if (ActivityCompat.checkSelfPermission(MainActivityForClass, Manifest.permission.RECORD_AUDIO) != PackageManager.PERMISSION_GRANTED) {
-                // TODO: Consider calling
-                //    ActivityCompat#requestPermissions
-                // here to request the missing permissions, and then overriding
-                //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
-                //                                          int[] grantResults)
-                // to handle the case where the user grants the permission. See the documentation
-                // for ActivityCompat#requestPermissions for more details.
-                ActivityCompat.requestPermissions(MainActivityForClass, new String[]{Manifest.permission.RECORD_AUDIO}, RECHTEANFORDERUNG_MIKROFON);
-            }
-
-            recorder = new AudioRecord(MediaRecorder.AudioSource.MIC, sampleRateInHz, channelConfig, audioFormat, pufferGroesseInBytes);
-
-            Log.d("0","Puffergroeße: "+ minPufferGroesseInBytes + " " + pufferGroesseInBytes);
-            Log.d("0","Recorder (SR, CH): "+ recorder.getSampleRate() + " " + recorder.getChannelCount());
-
-            int anzahlBytesProAbtastwert;
-            String s;
-            switch (recorder.getAudioFormat()) {
-                case AudioFormat.ENCODING_PCM_8BIT:
-                    s = "8 Bit PCM ";
-                    anzahlBytesProAbtastwert = 1;
-                    break;
-                case AudioFormat.ENCODING_PCM_16BIT:
-                    s = "16 Bit PCM";
-                    anzahlBytesProAbtastwert = 2;
-                    break;
-                case AudioFormat.ENCODING_PCM_FLOAT:
-                    s = "Float PCM";
-                    anzahlBytesProAbtastwert = 4;
-                    break;
-                default:
-                    throw new IllegalArgumentException();
-            }
-
-            switch (recorder.getChannelConfiguration()) {
-                case AudioFormat.CHANNEL_IN_MONO:
-                    s = "Mono";
-                    break;
-                case AudioFormat.CHANNEL_IN_STEREO:
-                    s = "Stereo";
-                    anzahlBytesProAbtastwert *= 2;
-                    break;
-                case AudioFormat.CHANNEL_INVALID:
-                    s = "ungültig";
-                    break;
-                default:
-                    throw new IllegalArgumentException();
-            }
-
-            Log.d("0","Konfiguration: "+ s);
-
-            int pufferGroesseInAnzahlAbtastwerten = pufferGroesseInBytes / anzahlBytesProAbtastwert;
-            int pufferGroesseInMillisekunden = 1000 * pufferGroesseInAnzahlAbtastwerten / recorder.getSampleRate();
-
-        }
-
-        @Override
-        protected Void doInBackground(Long... params) {
-            recorder.startRecording();
-            short[] puffer = new short[pufferGroesseInBytes / 2];
-            long lastTime = System.currentTimeMillis();
-            float verarbeitungsrate = 0;
-            final int maxZaehlerZeitMessung = 10;
-            int zaehlerZeitMessung = 0;
-            int anzahlVerarbeitet = 0;
-            GleitenderMittelwert gleitenderMittelwert = new GleitenderMittelwert(0.3f);
-
-            //Kalibrierung
-            try {
-                Thread.sleep(3000); // Time to lay down the phone
-            } catch (InterruptedException e) {
-                e.printStackTrace();
-            }
-            int i = 0;
-            for (i = 0; i < 20; i++) {
-                int n = recorder.read(puffer, 0, puffer.length);
-                Verarbeitungsergebnis kalibrierErgebnis = verarbeiten(puffer, n);
-                kalibierWert += kalibrierErgebnis.maxAmp;
-                try {
-                    Thread.sleep(50);
-                } catch (InterruptedException e) {
-                    e.printStackTrace();
-                }
-            }
-            kalibierWert = kalibierWert/i;
-
-//            __Part of FFT__
-//            Complex[] zeitSignal = new Complex[puffer.length];
-//            for (int j = 0; j < puffer.length; j++) {
-//                zeitSignal[j] = new Complex(puffer[j], 0);
-//            }
-//            Complex[] spektrum = FFT.fft(zeitSignal);
-//            double[] spektrum = calculateFFT(puffer);
-//            DataPoint AddPoint;
-//            LineGraphSeries<DataPoint> series = new LineGraphSeries<DataPoint>(new DataPoint[]{});
-//            for (i = 0; i < spektrum.length; i++) {
-//                AddPoint = new DataPoint(i, spektrum[i]);
-//                series.appendData(AddPoint, true, spektrum.length);
-//            }
-//            graph.addSeries(series);
-
-            for (; ; ) {
-                if (aufnahmeTask.isCancelled()) {
-                    break;
-                } else {
-                    int n = recorder.read(puffer, 0, puffer.length);
-                    Verarbeitungsergebnis ergebnis = verarbeiten(puffer, n);
-                    anzahlVerarbeitet += n;
-//                    __Part of FFT__
-//                    spektrum = calculateFFT(puffer);
-//                    LineGraphSeries<DataPoint> newseries = new LineGraphSeries<DataPoint>(new DataPoint[]{});
-//                    for (i = 0; i < spektrum.length; i++) {
-//                        AddPoint = new DataPoint(i, spektrum[i]);
-//                        newseries.appendData(AddPoint, true, spektrum.length);
-//                    }
-
-                    zaehlerZeitMessung++;
-                    if (zaehlerZeitMessung == maxZaehlerZeitMessung) {
-                        long time = System.currentTimeMillis();
-                        long deltaTime = time - lastTime;
-                        verarbeitungsrate = 1000.0f * anzahlVerarbeitet / deltaTime;
-                        verarbeitungsrate = gleitenderMittelwert.mittel(verarbeitungsrate);
-                        zaehlerZeitMessung = 0;
-                        anzahlVerarbeitet = 0;
-                        lastTime = time;
-                    }
-
-
-                    ergebnis.verarbeitungsrate = (int) verarbeitungsrate;
-                    publishProgress(ergebnis);
-
-                    try {
-                        Thread.sleep(10);
-                    } catch (InterruptedException e) {
-                        e.printStackTrace();
-                    }
-                }
-            }
-            recorder.release();
-            return null;
-        }
-
-        private Verarbeitungsergebnis verarbeiten(short[] daten, int n) {
-            String status;
-            short maxAmp = -1;
-            if (n == AudioRecord.ERROR_INVALID_OPERATION) {
-                status = "ERROR_INVALID_OPERATION";
-            } else if (n == AudioRecord.ERROR_BAD_VALUE) {
-                status = "ERROR_BAD_VALUE";
-            } else {
-                status = "OK";
-                short max = 0;
-                for (int i = 0; i < n; i++) {
-                    if (daten[i] > max) {
-                        max = daten[i];
-                    }
-                }
-
-                ringPuffer.hinzufuegen(max);
-                maxAmp = ringPuffer.maximum();
-                if (maxAmp <= Schwellwert_Alarm+kalibierWert) {
-                    armed = true;
-                }
-            }
-
-            return new Verarbeitungsergebnis(status, maxAmp, 0);
-        }
-
-        @Override
-        protected void onProgressUpdate(Verarbeitungsergebnis... progress) {
-            super.onProgressUpdate(progress);
-            float maxAmpPrint = round(20*log10(abs(progress[0].maxAmp/1.0)));
-            float kalibierWertPrint = round(20*log10(abs(kalibierWert)));
-            Log.d("0","VR, Max, Kal:" + progress[0].verarbeitungsrate + ", " + maxAmpPrint
-            + " dB, " + kalibierWertPrint + " dB");
-
-            if (progress[0].maxAmp >= Schwellwert_Alarm+kalibierWert && armed == true) {
-                armed = false;
-                detectionReport = new DetectionReport("Mic1", "Audio", maxAmpPrint);
-                reportViolation("Mic1", "Audio", maxAmpPrint);
-                Log.d("1",detectionReport.toString());
-            }
-        }
-    }
-
-    private double[] calculateFFT(short[] zeitsignal)
-    {
-        byte signal[] = new byte[zeitsignal.length];
-        // loops through all the values of a Short
-        for (int i = 0; i < zeitsignal.length-1; i++) {
-            signal[i] = (byte) (zeitsignal[i]);
-            signal[i+1] = (byte) (zeitsignal[i] >> 8);
-        }
-
-        final int mNumberOfFFTPoints =1024;
-        double mMaxFFTSample;
-
-        double temp;
-        Complex[] y;
-        Complex[] complexSignal = new Complex[mNumberOfFFTPoints];
-        double[] absSignal = new double[mNumberOfFFTPoints/2];
-
-        for(int i = 0; i < mNumberOfFFTPoints; i++){
-            temp = (double)((signal[2*i] & 0xFF) | (signal[2*i+1] << 8)) / 32768.0F;
-            complexSignal[i] = new Complex(temp,0.0);
-        }
-
-        y = FFT.fft(complexSignal);
-
-        mMaxFFTSample = 0.0;
-        for(int i = 0; i < (mNumberOfFFTPoints/2); i++)
-        {
-            absSignal[i] = y[i].abs();
-//            absSignal[i] = Math.sqrt(Math.pow(y[i].re(), 2) + Math.pow(y[i].im(), 2));
-//            if(absSignal[i] > mMaxFFTSample)
-//            {
-//                mMaxFFTSample = absSignal[i];
-//            }
-        }
-
-        return absSignal;
-
-    }
-
-    class Verarbeitungsergebnis {
-        String status;
-        short maxAmp;
-        int verarbeitungsrate;
-        Verarbeitungsergebnis(String status, short maxAmp, int verarbeitungsrate) {
-            this.status = status;
-            this.maxAmp = maxAmp;
-            this.verarbeitungsrate = verarbeitungsrate;
-        }
-    }
-
-    class RingPuffer {
-        private short[] puffer;
-        private final int laenge;
-        private int anzahlEnthaltenerDaten;
-        private int position;
-
-        public RingPuffer(int n) {
-            laenge = n;
-            anzahlEnthaltenerDaten = 0;
-            position = 0;
-            puffer = new short[laenge];
-        }
-
-        public void hinzufuegen(short wert) {
-            puffer[position] = wert;
-            position++;
-            if (position >= laenge) {
-                position = 0;
-            }
-            if (anzahlEnthaltenerDaten < laenge) {
-                anzahlEnthaltenerDaten++;
-            }
-        }
-
-        public void hinzufuegen(short[] daten) {
-            for (short d : daten) {
-                puffer[position] = d;
-                position++;
-                if (position >= laenge) {
-                    position = 0;
-                }
-            }
-            if (anzahlEnthaltenerDaten < laenge) {
-                anzahlEnthaltenerDaten += daten.length;
-                if (anzahlEnthaltenerDaten >= laenge) {
-                    anzahlEnthaltenerDaten = laenge;
-                }
-            }
-        }
-
-        public short maximum() {
-            short max = 0;
-            for (int i = 0; i < anzahlEnthaltenerDaten; i++) {
-                if (puffer[i] > max) {
-                    max = puffer[i];
-                }
-            }
-            return max;
-        }
-
-        public float mittelwert() {
-            float summe = 0;
-            for (int i = 0; i < anzahlEnthaltenerDaten; i++) {
-                summe += puffer[i];
-            }
-            return summe / anzahlEnthaltenerDaten;
-        }
-    }
-
-    class GleitenderMittelwert {
-        private final float wichtungNeuerWert;
-        private final float wichtungAlterWert;
-        private float mittelwert = 0;
-        private boolean istMittelwertGesetzt = false;
-
-        GleitenderMittelwert(float wichtungNeuerWert) {
-            this.wichtungNeuerWert = wichtungNeuerWert;
-            this.wichtungAlterWert = 1 - this.wichtungNeuerWert;
-        }
-
-        float MittelwertPuffer(short[] puffer) {
-
-            for (int i = 0; i < puffer.length; i++) {
-                mittelwert = Math.abs(puffer[i]);
-            }
-            mittelwert = mittelwert/puffer.length;
-
-            return mittelwert;
-        }
-
-        float mittel(float wert) {
-            if (istMittelwertGesetzt) {
-                mittelwert = wert * wichtungNeuerWert + mittelwert * wichtungAlterWert;
-            } else {
-                mittelwert = wert;
-                istMittelwertGesetzt = true;
-            }
-            return mittelwert;
-        }
-    }
-}

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

@@ -1,148 +0,0 @@
-package com.example.ueberwachungssystem.Detector.Signalverarbeitung;
-
-import java.util.Objects;
-
-public class Complex {
-    private final double re;   // the real part
-    private final double im;   // the imaginary part
-
-    // create a new object with the given real and imaginary parts
-    public Complex(double real, double imag) {
-        re = real;
-        im = imag;
-    }
-
-    // return a string representation of the invoking com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object
-    public String toString() {
-        if (im == 0) return re + "";
-        if (re == 0) return im + "i";
-        if (im < 0) return re + " - " + (-im) + "i";
-        return re + " + " + im + "i";
-    }
-
-    // return abs/modulus/magnitude
-    public double abs() {
-        return Math.hypot(re, im);
-    }
-
-    // return angle/phase/argument, normalized to be between -pi and pi
-    public double phase() {
-        return Math.atan2(im, re);
-    }
-
-    // return a new com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object whose value is (this + b)
-    public Complex plus(Complex b) {
-        Complex a = this;             // invoking object
-        double real = a.re + b.re;
-        double imag = a.im + b.im;
-        return new Complex(real, imag);
-    }
-
-    // return a new com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object whose value is (this - b)
-    public Complex minus(Complex b) {
-        Complex a = this;
-        double real = a.re - b.re;
-        double imag = a.im - b.im;
-        return new Complex(real, imag);
-    }
-
-    // return a new com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object whose value is (this * b)
-    public Complex times(Complex b) {
-        Complex a = this;
-        double real = a.re * b.re - a.im * b.im;
-        double imag = a.re * b.im + a.im * b.re;
-        return new Complex(real, imag);
-    }
-
-    // return a new object whose value is (this * alpha)
-    public Complex scale(double alpha) {
-        return new Complex(alpha * re, alpha * im);
-    }
-
-    // return a new com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object whose value is the conjugate of this
-    public Complex conjugate() {
-        return new Complex(re, -im);
-    }
-
-    // return a new com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object whose value is the reciprocal of this
-    public Complex reciprocal() {
-        double scale = re * re + im * im;
-        return new Complex(re / scale, -im / scale);
-    }
-
-    // return the real or imaginary part
-    public double re() {
-        return re;
-    }
-
-    public double im() {
-        return im;
-    }
-
-    // return a / b
-    public Complex divides(Complex b) {
-        Complex a = this;
-        return a.times(b.reciprocal());
-    }
-
-    // return a new com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object whose value is the complex exponential of this
-    public Complex exp() {
-        return new Complex(Math.exp(re) * Math.cos(im), Math.exp(re) * Math.sin(im));
-    }
-
-    // return a new com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object whose value is the complex sine of this
-    public Complex sin() {
-        return new Complex(Math.sin(re) * Math.cosh(im), Math.cos(re) * Math.sinh(im));
-    }
-
-    // return a new com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object whose value is the complex cosine of this
-    public Complex cos() {
-        return new Complex(Math.cos(re) * Math.cosh(im), -Math.sin(re) * Math.sinh(im));
-    }
-
-    // return a new com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex object whose value is the complex tangent of this
-    public Complex tan() {
-        return sin().divides(cos());
-    }
-
-    // a static version of plus
-    public static Complex plus(Complex a, Complex b) {
-        double real = a.re + b.re;
-        double imag = a.im + b.im;
-        Complex sum = new Complex(real, imag);
-        return sum;
-    }
-
-    // See Section 3.3.
-    public boolean equals(Object x) {
-        if (x == null) return false;
-        if (this.getClass() != x.getClass()) return false;
-        Complex that = (Complex) x;
-        return (this.re == that.re) && (this.im == that.im);
-    }
-
-    // See Section 3.3.
-    public int hashCode() {
-        return Objects.hash(re, im);
-    }
-
-    // sample client for testing
-    public static void main(String[] args) {
-        Complex a = new Complex(5.0, 6.0);
-        Complex b = new Complex(-3.0, 4.0);
-
-        System.out.println("a            = " + a);
-        System.out.println("b            = " + b);
-        System.out.println("Re(a)        = " + a.re());
-        System.out.println("Im(a)        = " + a.im());
-        System.out.println("b + a        = " + b.plus(a));
-        System.out.println("a - b        = " + a.minus(b));
-        System.out.println("a * b        = " + a.times(b));
-        System.out.println("b * a        = " + b.times(a));
-        System.out.println("a / b        = " + a.divides(b));
-        System.out.println("(a / b) * b  = " + a.divides(b).times(b));
-        System.out.println("conj(a)      = " + a.conjugate());
-        System.out.println("|a|          = " + a.abs());
-        System.out.println("tan(a)       = " + a.tan());
-    }
-}

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

@@ -1,246 +0,0 @@
-package com.example.ueberwachungssystem.Detector.Signalverarbeitung;
-// Source: https://introcs.cs.princeton.edu/java/97data/FFT.java.html
-
-/******************************************************************************
- *  Compilation:  javac FFT.java
- *  Execution:    java FFT n
- *  Dependencies: com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex.java
- *
- *  Compute the FFT and inverse FFT of a length n complex sequence
- *  using the radix 2 Cooley-Tukey algorithm.
- *  Bare bones implementation that runs in O(n log n) time and O(n)
- *  space. Our goal is to optimize the clarity of the code, rather
- *  than performance.
- *
- *  This implementation uses the primitive root of unity w = e^(-2 pi i / n).
- *  Some resources use w = e^(2 pi i / n).
- *
- *  Reference: https://www.cs.princeton.edu/~wayne/kleinberg-tardos/pdf/05DivideAndConquerII.pdf
- *
- *  Limitations
- *  -----------
- *   -  assumes n is a power of 2
- *
- *   -  not the most memory efficient algorithm (because it uses
- *      an object type for representing complex numbers and because
- *      it re-allocates memory for the subarray, instead of doing
- *      in-place or reusing a single temporary array)
- *
- *  For an in-place radix 2 Cooley-Tukey FFT, see
- *  https://introcs.cs.princeton.edu/java/97data/InplaceFFT.java.html
- *
- ******************************************************************************/
-
-public class FFT {
-
-    // compute the FFT of x[], assuming its length n is a power of 2
-    public static Complex[] fft(Complex[] x) {
-        int n = x.length;
-
-        // base case
-        if (n == 1) return new Complex[]{x[0]};
-
-        // radix 2 Cooley-Tukey FFT
-        if (n % 2 != 0) {
-            throw new IllegalArgumentException("n is not a power of 2");
-        }
-
-        // compute FFT of even terms
-        Complex[] even = new Complex[n / 2];
-        for (int k = 0; k < n / 2; k++) {
-            even[k] = x[2 * k];
-        }
-        Complex[] evenFFT = fft(even);
-
-        // compute FFT of odd terms
-        Complex[] odd = even;  // reuse the array (to avoid n log n space)
-        for (int k = 0; k < n / 2; k++) {
-            odd[k] = x[2 * k + 1];
-        }
-        Complex[] oddFFT = fft(odd);
-
-        // combine
-        Complex[] y = new Complex[n];
-        for (int k = 0; k < n / 2; k++) {
-            double kth = -2 * k * Math.PI / n;
-            Complex wk = new Complex(Math.cos(kth), Math.sin(kth));
-            y[k] = evenFFT[k].plus(wk.times(oddFFT[k]));
-            y[k + n / 2] = evenFFT[k].minus(wk.times(oddFFT[k]));
-        }
-        return y;
-    }
-
-
-    // compute the inverse FFT of x[], assuming its length n is a power of 2
-    public static Complex[] ifft(Complex[] x) {
-        int n = x.length;
-        Complex[] y = new Complex[n];
-
-        // take conjugate
-        for (int i = 0; i < n; i++) {
-            y[i] = x[i].conjugate();
-        }
-
-        // compute forward FFT
-        y = fft(y);
-
-        // take conjugate again
-        for (int i = 0; i < n; i++) {
-            y[i] = y[i].conjugate();
-        }
-
-        // divide by n
-        for (int i = 0; i < n; i++) {
-            y[i] = y[i].scale(1.0 / n);
-        }
-
-        return y;
-
-    }
-
-    // compute the circular convolution of x and y
-    public static Complex[] cconvolve(Complex[] x, Complex[] y) {
-
-        // should probably pad x and y with 0s so that they have same length
-        // and are powers of 2
-        if (x.length != y.length) {
-            throw new IllegalArgumentException("Dimensions don't agree");
-        }
-
-        int n = x.length;
-
-        // compute FFT of each sequence
-        Complex[] a = fft(x);
-        Complex[] b = fft(y);
-
-        // point-wise multiply
-        Complex[] c = new Complex[n];
-        for (int i = 0; i < n; i++) {
-            c[i] = a[i].times(b[i]);
-        }
-
-        // compute inverse FFT
-        return ifft(c);
-    }
-
-
-    // compute the linear convolution of x and y
-    public static Complex[] convolve(Complex[] x, Complex[] y) {
-        Complex ZERO = new Complex(0, 0);
-
-        Complex[] a = new Complex[2 * x.length];
-        for (int i = 0; i < x.length; i++) a[i] = x[i];
-        for (int i = x.length; i < 2 * x.length; i++) a[i] = ZERO;
-
-        Complex[] b = new Complex[2 * y.length];
-        for (int i = 0; i < y.length; i++) b[i] = y[i];
-        for (int i = y.length; i < 2 * y.length; i++) b[i] = ZERO;
-
-        return cconvolve(a, b);
-    }
-
-    // compute the DFT of x[] via brute force (n^2 time)
-    public static Complex[] dft(Complex[] x) {
-        int n = x.length;
-        Complex ZERO = new Complex(0, 0);
-        Complex[] y = new Complex[n];
-        for (int k = 0; k < n; k++) {
-            y[k] = ZERO;
-            for (int j = 0; j < n; j++) {
-                int power = (k * j) % n;
-                double kth = -2 * power * Math.PI / n;
-                Complex wkj = new Complex(Math.cos(kth), Math.sin(kth));
-                y[k] = y[k].plus(x[j].times(wkj));
-            }
-        }
-        return y;
-    }
-
-    // display an array of com.example.ueberwachungssystem.Detector.Signalverarbeitung.Complex numbers to standard output
-    public static void show(Complex[] x, String title) {
-        System.out.println(title);
-        System.out.println("-------------------");
-        for (int i = 0; i < x.length; i++) {
-            System.out.println(x[i]);
-        }
-        System.out.println();
-    }
-
-    /***************************************************************************
-     *  Test client and sample execution
-     *
-     *  % java FFT 4
-     *  x
-     *  -------------------
-     *  -0.03480425839330703
-     *  0.07910192950176387
-     *  0.7233322451735928
-     *  0.1659819820667019
-     *
-     *  y = fft(x)
-     *  -------------------
-     *  0.9336118983487516
-     *  -0.7581365035668999 + 0.08688005256493803i
-     *  0.44344407521182005
-     *  -0.7581365035668999 - 0.08688005256493803i
-     *
-     *  z = ifft(y)
-     *  -------------------
-     *  -0.03480425839330703
-     *  0.07910192950176387 + 2.6599344570851287E-18i
-     *  0.7233322451735928
-     *  0.1659819820667019 - 2.6599344570851287E-18i
-     *
-     *  c = cconvolve(x, x)
-     *  -------------------
-     *  0.5506798633981853
-     *  0.23461407150576394 - 4.033186818023279E-18i
-     *  -0.016542951108772352
-     *  0.10288019294318276 + 4.033186818023279E-18i
-     *
-     *  d = convolve(x, x)
-     *  -------------------
-     *  0.001211336402308083 - 3.122502256758253E-17i
-     *  -0.005506167987577068 - 5.058885073636224E-17i
-     *  -0.044092969479563274 + 2.1934338938072244E-18i
-     *  0.10288019294318276 - 3.6147323062478115E-17i
-     *  0.5494685269958772 + 3.122502256758253E-17i
-     *  0.240120239493341 + 4.655566391833896E-17i
-     *  0.02755001837079092 - 2.1934338938072244E-18i
-     *  4.01805098805014E-17i
-     *
-     ***************************************************************************/
-
-    public static void main(String[] args) {
-        int n = Integer.parseInt(args[0]);
-        Complex[] x = new Complex[n];
-
-        // original data
-        for (int i = 0; i < n; i++) {
-            x[i] = new Complex(i, 0);
-        }
-        show(x, "x");
-
-        // FFT of original data
-        Complex[] y = fft(x);
-        show(y, "y = fft(x)");
-
-        // FFT of original data
-        Complex[] y2 = dft(x);
-        show(y2, "y2 = dft(x)");
-
-        // take inverse FFT
-        Complex[] z = ifft(y);
-        show(z, "z = ifft(y)");
-
-        // circular convolution of x with itself
-        Complex[] c = cconvolve(x, x);
-        show(c, "c = cconvolve(x, x)");
-
-        // linear convolution of x with itself
-        Complex[] d = convolve(x, x);
-        show(d, "d = convolve(x, x)");
-    }
-}
-
-

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

@@ -2,66 +2,73 @@ 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.util.Log;
 import android.view.View;
-import android.widget.Switch;
 import android.widget.TextView;
+import android.widget.Toast;
+import android.widget.ToggleButton;
+import android.widget.VideoView;
 
-import com.example.ueberwachungssystem.Detector.DetectionReport;
+import com.example.ueberwachungssystem.VideoDetection.VideoDetector;
-import com.example.ueberwachungssystem.Detector.Detector;
-import com.example.ueberwachungssystem.Detector.MicrophoneDetector;
-import com.jjoe64.graphview.GraphView;
-
 
+@ExperimentalGetImage
 public class MainActivity extends AppCompatActivity {
-    private TextView tv_log;
+
-    MicrophoneDetector Mic;
+    private static final int CAMERA_PERMISSION_REQUEST_CODE = 100;
-    private Switch TglBtn_Mic;
+    private static final int RECORD_VIDEO_PERMISSION_REQUEST_CODE = 102;
+
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
-        tv_log = (TextView) findViewById(R.id.tv_log); //Set textview for showing logged content
+
-        Log.d("Main",this.getClass().getSimpleName() + ".onCreate");
+        TextView textView = findViewById(R.id.textView);
-        Mic = new MicrophoneDetector(this);
+        PreviewView previewView = findViewById(R.id.previewView);
-        setupMic();
+
-        Mic.setOnDetectionListener(new Detector.OnDetectionListener() {
+        getCameraAccess();
+
+        VideoDetector vd = new VideoDetector(this);
+        vd.setPreviewView(previewView);
+        vd.setOnDetectionListener(new VideoDetector.OnDetectionListener() {
             @Override
             public void onDetection(@NonNull DetectionReport detectionReport) {
-                Log.d("Main", "Detection erkannt!");
+                detectionReport.log("OnDetection");
+                textView.setText("Alarm:\t[" + String.valueOf(detectionReport.detectedValue) + "]");
             }
         });
+        vd.startDetection();
 
     }
 
+    private boolean isCameraAccessAllowed() {
+        return ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED;
+    }
+
+    private void getCameraAccess() {
+        if (!isCameraAccessAllowed())
+            ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.CAMERA}, CAMERA_PERMISSION_REQUEST_CODE);
+    }
+
     @Override
-    public void onResume() {
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
-        super.onResume();
+        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
-        Log.d("Main",this.getClass().getSimpleName() + ".onResume");
-    }
 
-    @Override
+        if (requestCode == CAMERA_PERMISSION_REQUEST_CODE && grantResults.length > 0) {
-    public void onPause() {
+            boolean cameraRights = grantResults[0] == PackageManager.PERMISSION_GRANTED;
-        super.onPause();
+            if (cameraRights) {
-        Log.d("Main",this.getClass().getSimpleName() + ".onPause");
+                Toast.makeText(this, "permission granted", Toast.LENGTH_LONG).show();
-    }
+            } else {
-
+                Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show();
-    private void setupMic() {
-        TglBtn_Mic = (Switch) findViewById(R.id.TglBtn_Mic);
-        TglBtn_Mic.setOnClickListener(new View.OnClickListener() {
-            @Override
-            public void onClick(View v) {
-                if (v == TglBtn_Mic) {
-                    Log.d("Main","onClick toggleButtonThread " + TglBtn_Mic.isChecked());
-                    if (TglBtn_Mic.isChecked()) {
-                        Mic.startDetection();
-                    } else {
-                        Mic.stopDetection();
-                    }
-                }
             }
-        });
+        }
     }
 }

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

@@ -0,0 +1,166 @@
+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 = 0.5f;   // 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.unbindAll();
+        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

@@ -1,26 +1,34 @@
 <?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/tv_log"
+        android:id="@+id/textView"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:text="Log"
+        android:text=""
+        android:textSize="30sp"
+        app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toBottomOf="@+id/TglBtn_Mic" />
-
-    <Switch
-        android:id="@+id/TglBtn_Mic"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:text="Mic"
-        app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintTop_toTopOf="parent" />
 
-</androidx.constraintlayout.widget.ConstraintLayout>
+
+
+
+    <androidx.camera.view.PreviewView
+        android:id="@+id/previewView"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:backgroundTint="@android:color/black">
+
+    </androidx.camera.view.PreviewView>
+
+</LinearLayout>

gradle.properties

@@ -18,5 +18,4 @@ android.useAndroidX=true
 # Enables namespacing of each library's R class so that its R class includes only the
 # 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.nonTransitiveRClass=true
-android.enableJetifier=true