hi there folks!

i’m trying to write a live-beatdetection-app that sends values over OSC to any other application…
but… right now im stuck, i get a nullpointer.

i think that the problem lies with the in-class-instance of minim… am i right?
i once used processing in eclipse and learned by passing "this" through the constructor that this should be possible.

or i’m just missing something?


small overview:

i wanted to create a class that combines the complete audioanalysispart – AudioAnalyzer
the values of the bins are updated in every draw – AudioAnalyzer.update(), instanced as aa.update()
the values of the bins are stored in a float-array inside the class – AudioAnalyzer.m_frequencyBins[]

the sketch

1. import processing.opengl.*;
   import ddf.minim.*;
   import ddf.minim.analysis.*;
   
   AudioAnalyzer aa;
   int binwidth;
   
   void setup()
   {
     size(800, 600, OPENGL);
     frameRate(60);
    
     aa = new AudioAnalyzer(this);
   }
   
   
   void draw()
   {
     // updates the fft
     aa.update();
   
     // should draw the freq-144 bands
     for (int index = 0; index < aa.m_frequencyBins.length; index++)
     {
       rect(index*binwidth, 0, index*binwidth+binwidth, aa.m_frequencyBins[index]*3);
     }
   }
   
   
   
   void stop()
   {
     aa.m_audio.close();
     aa.m_minim.stop();
     super.stop();
   }
   
   

the class

1. class AudioAnalyzer
   {
   
     // audioanalysis stuff
     Minim         m_minim;
     AudioInput    m_audio;
     FFT           m_fft;
   
     float[]       m_frequencyBins;
    
   
     AudioAnalyzer(PApplet p_parent)
     {
      
       // instance all the audio-libs
       m_minim =        new Minim(p_parent);
       m_audio =        m_minim.getLineIn(Minim.STEREO, 2048);
       m_fft =          new FFT(m_audio.bufferSize(), m_audio.sampleRate());
   
   
       // set the logarithmic fft up
       m_fft.logAverages(50, 16);
      
      
       // empty array for the bins
       float[] m_frequencyBins = new float[m_fft.avgSize()];
      
       for (int i = 0; i < m_frequencyBins.length; i++ ) {
         m_frequencyBins[i] = 0.0;
         println(m_fft.getAvg(i));
       }
      
      
     }
   
     float band(int p_index)
     {
       return m_fft.getAvg(p_index);
     }
   
   
     void update()
     {
   
       m_fft.forward(m_audio.mix);
   
       // write the freq-bins into an array
       for (int i = 0; i < m_frequencyBins.length; i++ ) {
         println(i);
         m_frequencyBins[i] = m_fft.getAvg(i); // <<<<<<<< NULLPOINTER :(
       }
     }
   }
   

thanks for any help!
gabriel