how to make a music visualization using beat detect and random lines

ashlolsn

I'm new at processing and am having difficulties figuring out how to make a very basic music visualization using beat detect or being time based. I want to incorporate a random line for every beat. Anyone able to help? So far, this is all I've got (I'm brand new at this).

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

Minim minim; AudioPlayer song; BeatDetect beat;

void setup() { size(1000,550); minim = new Minim(this); song = minim.loadFile("Breeze.mp3"); song.play();

}

void draw() { background(0);

}

TfGuy44

Having never done beat detecting myself, I did a quick google search to see what I could find. This came up:

http://code.compartmental.net/minim/javadoc/ddf/minim/analysis/BeatDetect.html

So you're in the right area. With a little finagling, I got this working! YEAH! Here:

/**
  * This sketch demonstrates how to use an FFT to analyze
  * the audio being generated by an AudioPlayer.
  * <p>
  * FFT stands for Fast Fourier Transform, which is a 
  * method of analyzing audio that allows you to visualize 
  * the frequency content of a signal. You've seen 
  * visualizations like this before in music players 
  * and car stereos.
  * <p>
  * For more information about Minim and additional features, 
  * visit http://code.compartmental.net/minim/
  */

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

BeatDetect heart = new BeatDetect();
Minim       minim;
AudioPlayer jingle;
FFT         fft;

void setup()
{
  size(512, 200, P3D);

  minim = new Minim(this);

  // specify that we want the audio buffers of the AudioPlayer
  // to be 1024 samples long because our FFT needs to have 
  // a power-of-two buffer size and this is a good size.
  jingle = minim.loadFile("jingle.mp3", 1024);

  // loop the file indefinitely
  jingle.loop();

  // create an FFT object that has a time-domain buffer 
  // the same size as jingle's sample buffer
  // note that this needs to be a power of two 
  // and that it means the size of the spectrum will be half as large.
  fft = new FFT( jingle.bufferSize(), jingle.sampleRate() );

}

void draw()
{
  background(0);
  heart.detect( jingle.right );  
  if( heart.isOnset() ){
    background(255,0,0);
  }

  stroke(255);

  // perform a forward FFT on the samples in jingle's mix buffer,
  // which contains the mix of both the left and right channels of the file
  fft.forward( jingle.right );

  for(int i = 0; i < fft.specSize(); i++)
  {
    // draw the line for frequency band i, scaling it up a bit so we can see it
    line( i, height, i, height - fft.getBand(i)*8 );
  }
}

ashlolsn

This is great! Thank you! I wasn't trying to go for the heart detect, but this is getting much closer to what I'm trying to get.

Instead of the heart detect, is there a way to just generate random lines all over the sketch with random x & y points?

TfGuy44

Well yeah. I assumed your problem was getting the detecting to work. The random lines bit is easy. Just pick two random x values using random(width), and two random Y values using random(height), and draw a line using line() (and possibly coloring it with stroke()).

Post the code of your attempt at it for more help.