Help with analyzing file with Sound Library

Processing Beginners
1

Hello, I am extremely new to coding so apologies if my formatting or knowledge is off.
I am trying to analyze a sound file using the Sound Library and display a visualization of it using the Fast Fourier Transform (FFT) analyzer. However, I am getting this NullPointerException when trying to run it.

Mar 06, 2023 2:02:22 PM com.jsyn.devices.javasound.JavaSoundAudioDevice <init>
INFO: JSyn: default output latency set to 80 msec for Windows 11
NullPointerException

This is the highlighted line
fft.analyze();

This is the entire code

//sound
import processing.sound.*;
SoundFile soundfile;
FFT fft;

int bands = 32; //(8,16,32,64,128,256,512,1024)
float margin = 100;
float stepNum;
float stepPlus;

void setup(){
  background(0);
  size(1200,1200);
  frameRate(8);

  //sound
  soundfile = new SoundFile(this, "sample.wav"); //(60*8)
  soundfile.play();

  //analyze
  fft.analyze();
  stepNum = (width-margin*2)/bands;
  stepPlus = (width-margin*2)/(60*8); //second framecount
}

void draw(){
  //background(0);
  //noStroke();
  //fill(0,30);
  //rect(0,0,width,height);

  stroke(255,70);
  smooth();
  noFill();
  fft.analyze();

  if (stepNum < width - margin*2){
    for(int i=0; i < bands; ++i){
      strokeWeight(fft.spectrum[i]*50+1);
      for (float j = 0; j < 10; ++j) {
        float ali = random(360);
        float ran = (fft.spectrum[i]*width/5+1) * (1 - random(random(random(1))));
        point(cos(ali)*ran+stepNum+margin, sin(ali)*ran+i*(height-margin*2)/float(bands)+margin);
      }
    }
  }
  stepNum += stepPlus;
}

Thank you!

2

Hello @andew,

What version of Processing are you using?

I suggest you scrutnize and try a working example that comes with Processing:

image
image371×538 21.4 KB

:)

3

Hi @andew,

You forgot to initialize FFT.

As @glv suggesting start by study examples and references beforehand…

Cheers
— mnse