added SampleBuffer, added Spectrum to AudioProcessing

AudioProcessing/src/main/java/org/wyrez/audio/AudioProcessor.java

@@ -26,24 +26,26 @@ import java.util.List;
 import org.wyrez.audio.analysis.FFT;
 import org.wyrez.audio.decoder.Decoder;
 import org.wyrez.audio.util.Band;
+import org.wyrez.audio.util.SampleBuffer;
 import org.wyrez.audio.util.SampleHelper;
 
 /**
- * Processor to create analysis-data of audio samples
- *
+ *Processor to create analysis-data of audio samples
+ * 
  * @author Darth Affe
  */
 public class AudioProcessor {
 
     private Band band;
     private int bufferSize;
-    private final float[] samples;
+    private SampleBuffer sampleBuffer;
+    private float[] spectrum;
     private float[] spectralFlux;
     private float[] threshold;
     private float[] prunedSpectralFlux;
     private float[] peaks;
     private float peakAverage;
-    private final float samplingRate;
+    private float samplingRate;
     private float bpm;
 
     /**
@@ -52,8 +54,7 @@ public class AudioProcessor {
      * @param decoder The decoder to process
      */
     public AudioProcessor(Decoder decoder) {
-        this.samples = SampleHelper.readAllSamples(decoder);
-        this.samplingRate = decoder.getSamplingRate();
+        this(SampleHelper.createSampleBuffer(decoder));
     }
 
     /**
@@ -64,8 +65,16 @@ public class AudioProcessor {
      * @param band The band to process
      */
     public AudioProcessor(Decoder decoder, Band band) {
-        this.samples = SampleHelper.readAllSamples(decoder);
-        this.samplingRate = decoder.getSamplingRate();
+        this(SampleHelper.createSampleBuffer(decoder), band);
+    }
+
+    public AudioProcessor(SampleBuffer sampleBuffer) {
+        this(sampleBuffer, null);
+    }
+
+    public AudioProcessor(SampleBuffer sampleBuffer, Band band) {
+        this.sampleBuffer = sampleBuffer;
+        this.samplingRate = sampleBuffer.samplingRate;
         this.band = band;
     }
 
@@ -73,6 +82,7 @@ public class AudioProcessor {
      * Removes cached objects to save some memory.
      */
     public void clean() {
+        spectrum = null;
         spectralFlux = null;
         threshold = null;
         prunedSpectralFlux = null;
@@ -170,24 +180,27 @@ public class AudioProcessor {
         FFT fft = new FFT(bufferSize, samplingRate);
         fft.window(FFT.HAMMING);
         float[] buffer;
-        float[] spectrum = new float[fft.getBandSize(band)];
-        float[] lastSpectrum = new float[spectrum.length];
+        float[] spectrumBuffer = new float[fft.getBandSize(band)];
+        float[] lastSpectrumBuffer = new float[spectrumBuffer.length];
+        List<Float> spectrum = new ArrayList<Float>();
         List<Float> spectralFlux = new ArrayList<Float>();
 
-        for (int i = 0; i < samples.length; i += bufferSize) {
-            buffer = SampleHelper.splitSampleArray(samples, i, bufferSize);
+        for (int i = 0; i < sampleBuffer.samples.length; i += bufferSize) {
+            buffer = SampleHelper.splitSampleArray(sampleBuffer.samples, i, bufferSize);
             fft.forward(buffer);
-            System.arraycopy(spectrum, 0, lastSpectrum, 0, spectrum.length);
-            System.arraycopy(fft.getSpectrum(band), 0, spectrum, 0, spectrum.length);
+            System.arraycopy(spectrumBuffer, 0, lastSpectrumBuffer, 0, spectrumBuffer.length);
+            System.arraycopy(fft.getSpectrum(band), 0, spectrumBuffer, 0, spectrumBuffer.length);
 
             float flux = 0;
-            for (int j = 0; j < spectrum.length; j++) {
-                float value = (spectrum[j] - lastSpectrum[j]);
+            for (int j = 0; j < spectrumBuffer.length; j++) {
+                spectrum.add(spectrumBuffer[j]);
+                float value = (spectrumBuffer[j] - lastSpectrumBuffer[j]);
                 flux += value < 0 ? 0 : value;
             }
             spectralFlux.add(flux);
         }
         this.spectralFlux = SampleHelper.convertToFloatArray(spectralFlux);
+        this.spectrum = SampleHelper.convertToFloatArray(spectrum);
     }
 
     private void calculateThreshold(int thresholdWindowSize, float multiplier) {
@@ -320,10 +333,19 @@ public class AudioProcessor {
     /**
      * Returns the samples which are analysed.
      *
-     * @returns A float array containing the samples
+     * @returns A SampleBuffer containing the samples
      */
-    public float[] getSamples() {
-        return samples;
+    public SampleBuffer getSampleBuffer() {
+        return sampleBuffer;
+    }
+
+    /**
+     * Returns the last calculated fft-spectrum.
+     *
+     * @returns A float array containing the spectrum data
+     */
+    public float[] getSpectrum() {
+        return spectrum;
     }
 
     /**

AudioProcessing/src/main/java/org/wyrez/audio/util/SampleBuffer.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2013 Darth Affe <http://wyrez.org> and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.wyrez.audio.util;
+
+/**
+ *
+ * @author Darth Affe
+ */
+public class SampleBuffer {
+
+    public final float[] samples;
+    public final float samplingRate;
+
+    public SampleBuffer(float[] samples, float samplingRate) {
+        this.samples = samples;
+        this.samplingRate = samplingRate;
+    }
+}

AudioProcessing/src/main/java/org/wyrez/audio/util/SampleHelper.java

@@ -97,4 +97,14 @@ public class SampleHelper {
         }
         return convertToFloatArray(samples);
     }
+
+    /**
+     * Creates a SampleBuffer from the data provided by the given decoder.
+     * 
+     * @param deocder The decoder to read from
+     * @returns The new SampleBuffer
+     */
+    public static SampleBuffer createSampleBuffer(Decoder decoder) {
+        return new SampleBuffer(readAllSamples(decoder), decoder.getSamplingRate());
+    }
 }