Matthew Yee-King

frequency domain filters parameterised

admin — Sat, 23 Mar 2013 04:44:34 +0000



import ddf.minim.analysis.*;
import ddf.minim.*;
import ddf.minim.signals.*;

int comb_width = 1;

AudioThread audioThread;
// we'll use this to store the audio data we read from the audio file
float[] audioData;
// we'll use this to remember our position in the audio data array
int readHead;

FFT fft;
//SineWave sine;
float[] buffer;
float[] out_buff;
int bsize = 4096;

void setup() {
  size(512, 500);
  // the audio file we want to play, which should be in the data dir
  String audioFilename = "amenloop.wav";
  // read the audio data into a float array using the AudioFileIn class
  audioData = new AudioFileIn(audioFilename, this).getSampleData();
  // print how many samples we read
  println("Read "+audioData.length+" samples");
  // set the read head to zero, the first sample
  readHead = 0;
  // start up the audio thread
  audioThread = new AudioThread();
  // fft code
  fft = new FFT(bsize, 44100);
  //fft.window(FFT.HAMMING);
  buffer = new float[bsize];
  // fill the buffer with a sine wave
  //sine.generate(buffer);

  audioThread.start();
}

void draw() {
  background(0);
  stroke(255);
  for (int i = 0; i < fft.specSize(); i++)
  {
    // draw the line for frequency band i, scaling it by 4 so we can see it a bit better
    line(i, height, i, height - fft.getBand(i)*4);
  }
}

// this function gets called when you press the escape key in the sketch
void stop() {
  // tell the audio to stop
  audioThread.quit();
  // call the version of stop defined in our parent class, in case it does anything vital
  super.stop();
}


// this gets called by the audio thread when it wants some audio
// we should fill the sent buffer with the audio we want to send to the 
// audio output
void generateAudioOut(float[] output) {


  for (int i=0;i

Frequency domain effects

admin — Sat, 23 Mar 2013 03:39:24 +0000


import ddf.minim.analysis.*;
import ddf.minim.*;
import ddf.minim.signals.*;

AudioThread audioThread;
// we'll use this to store the audio data we read from the audio file
float[] audioData;
// we'll use this to remember our position in the audio data array
int readHead;

FFT fft;
//SineWave sine;
float[] buffer;
float[] out_buff;
int bsize = 4096;

void setup() {
  size(512, 500);
  // the audio file we want to play, which should be in the data dir
  String audioFilename = "myk_hats_dub1.wav";
  // read the audio data into a float array using the AudioFileIn class
  audioData = new AudioFileIn(audioFilename, this).getSampleData();
  // print how many samples we read
  println("Read "+audioData.length+" samples");
  // set the read head to zero, the first sample
  readHead = 0;
  // start up the audio thread
  audioThread = new AudioThread();
  // fft code
  fft = new FFT(bsize, 44100);
  //fft.window(FFT.HAMMING);
  buffer = new float[bsize];
  // fill the buffer with a sine wave
  //sine.generate(buffer);

  audioThread.start();
}

void draw() {
  background(0);
  stroke(255);
  for (int i = 0; i < fft.specSize(); i++)
  {
    // draw the line for frequency band i, scaling it by 4 so we can see it a bit better
    line(i, height, i, height - fft.getBand(i)*4);
  }
}

// this function gets called when you press the escape key in the sketch
void stop() {
  // tell the audio to stop
  audioThread.quit();
  // call the version of stop defined in our parent class, in case it does anything vital
  super.stop();
}


// this gets called by the audio thread when it wants some audio
// we should fill the sent buffer with the audio we want to send to the 
// audio output
void generateAudioOut(float[] output) {


  for (int i=0;i

Spectral plotter

admin — Sat, 23 Mar 2013 02:49:36 +0000


import ddf.minim.analysis.*;
import ddf.minim.*;
import ddf.minim.signals.*;

AudioThread audioThread;
// we'll use this to store the audio data we read from the audio file
float[] audioData;
// we'll use this to remember our position in the audio data array
int readHead;
float speed = 1;

FFT fft;
//SineWave sine;
float[] buffer;
float[] out_buff;
int bsize = 4096;
boolean paused = false;
float[][] spectrum;


void setup() {
  size(500, 500);
  // the audio file we want to play, which should be in the data dir
  String audioFilename = "amenloop.wav";
  // read the audio data into a float array using the AudioFileIn class
  audioData = new AudioFileIn(audioFilename, this).getSampleData();
  // print how many samples we read
  println("Read "+audioData.length+" samples");
  // set the read head to zero, the first sample
  readHead = 0;
  // start up the audio thread
  audioThread = new AudioThread();
  // fft code
  fft = new FFT(bsize, 44100);
  buffer = new float[bsize];
  // fill the buffer with a sine wave
  //sine.generate(buffer);
  spectrum = fft(audioData);
  audioThread.start();
}

float[][] fft(float[] signal){
  int size = 1024;
   FFT fft = new FFT(size, 44100);

  float[] buffer = new float[1024];
  float[][] spectrum = new float[signal.length/buffer.length][buffer.length];
  for (int frame = 0; frame < spectrum.length; frame++){
    // copy some samples into the buffer
    arraycopy(signal, frame*buffer.length,
    buffer, 0, buffer.length);
    
    // calculate the power spectrum
    fft.forward(buffer);
    // store the results to the spectrum array
    for (int bin = 0; bin < fft.specSize()-1; bin++){
      println("gett frame "+frame+" bin "+bin+" of "+fft.specSize());
      spectrum[frame][bin] = fft.getBand(bin);
    }
  }
  return spectrum;
}

void draw() {
  background(0);
  stroke(255);
  speed = mouseX / 10;
  for (int frame = 0; frame < spectrum.length; frame++){
    float x = frame;
    for (int bin = 0; bin < spectrum[frame].length; bin++){
      float y = height - bin;
      float val = spectrum[frame][bin];
      stroke(val * 255);
      point(x, y);
    }
  }
}

void mousePressed() {
  paused = !paused;
}

// this function gets called when you press the escape key in the sketch
void stop() {
  // tell the audio to stop
  audioThread.quit();
  // call the version of stop defined in our parent class, in case it does anything vital
  super.stop();
}


// this gets called by the audio thread when it wants some audio
// we should fill the sent buffer with the audio we want to send to the 
// audio output
void generateAudioOut(float[] output) {
if (true){
  return;
}

  for (int i=0;i

Classic DFT Java tutorial

admin — Fri, 22 Mar 2013 15:03:38 +0000

You will not regret reading and understanding this tutorial

Updated convolution code

admin — Fri, 22 Mar 2013 06:53:27 +0000



AudioThread audioThread;
// we'll use this to store the audio data we read from the audio file
float[] signal;
float[] impulse;
float[] conv;
// we'll use this to remember our position in the audio data array
int readHead;


void setup() {
  size(50,50, P2D);
  String audioFilename = "909snr_tail.wav";
  signal = new AudioFileIn(audioFilename, this).getSampleData();
  impulse = new AudioFileIn("conv1441.wav", this).getSampleData();
  println("Read "+signal.length+" signal samples");
  println("Read "+impulse.length+" impulse samples ");
  // convolve for 10 seconds
// .... increase the number at the end to calc a longer output
  conv = convolve(signal, impulse, 44100 * 1);
  //conv = signal;
  readHead = 0;
  audioThread = new AudioThread();
  audioThread.start();
  
}
 
float[] convolve(float[] sig, float[] system, int length){
  float[] output = new float[length];
  // iterate over the input signal
  for (int sig_ind = 0; sig_ind < sig.length; sig_ind ++){
     println("calcing step "+sig_ind+" of "+sig.length+" : "+floor(((float) sig_ind/ (float) sig.length * 100))+" percent"); 
    for (int sys_ind = 0; (sys_ind+sig_ind) < length; sys_ind++){
      output[sys_ind+sig_ind] += sig[sig_ind] * 
      system[sys_ind % system.length];
    }
  }
  return output;
} 

void draw() {
  background(0); 
  
}

// this function gets called when you press the escape key in the sketch
void stop(){
  // tell the audio to stop
  audioThread.quit();
  // call the version of stop defined in our parent class, in case it does anything vital
  super.stop();
}


// this gets called by the audio thread when it wants some audio
// we should fill the sent buffer with the audio we want to send to the 
// audio output
void generateAudioOut(float[] buffer){
  for (int i=0;i

Wheat Field

simstudent — Fri, 22 Mar 2013 06:16:07 +0000

Hypnotic circle

simstudent — Fri, 22 Mar 2013 06:11:51 +0000

dizzy ball

simstudent — Fri, 22 Mar 2013 06:11:09 +0000

Dizzy Tunnel

simstudent — Fri, 22 Mar 2013 05:56:44 +0000

sin and cos colour

admin — Fri, 22 Mar 2013 05:46:14 +0000


void setup(){
 size(500, 500); 
}

void draw(){
  float x = 0;
  for (float phase = 0; x < height; phase+=TWO_PI/width * mouseX){
    float red, green;
    red = sin(phase); // -1 to 1
    red += 1; // 0 2
    red *= 0.5; // 0 1
    red *= 255; // 0-255
    green = (cos(phase)+1) * 0.5 * 255;
    stroke(red, green, 0);
    line(x,0,x, height);
    x ++;
  }
}