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Index › Programming Questions & Help › Sound, Music Libraries › 3D spectrum analyzer

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3D spectrum analyzer (Read 3641 times)

subzero

3D spectrum analyzer
Dec 16^th, 2007, 10:32pm

first post for me here, so first of all hi to all of you
i'm new to processing so let's go with the first question

i'm tryng to make a realtime 3D spectrum analyzer, something like this for those who are not in sound analysis:

i managed to draw a live input spectrum analyzer. now i think i have to repeat the spectrum line along the z axis, each line with the state of the previous one in the previous frame (ok i've been not so clear but i think you understand)

i think i have to use a class, but i've not found a good explanation of how it works.

anyway, this is the code:
Code:


import ddf.minim.*;
import ddf.minim.analysis.*;
import processing.opengl.*;

AudioInput stream;
FFT fft;

void setup()
{
  size(800, 800, OPENGL);
  Minim.start(this);
  stream = Minim.getLineIn(Minim.STEREO);
  fft = new FFT(stream.bufferSize(), stream.sampleRate());
}

void draw()
{
  background(0);
  camera(width, 0, (height/2.0) / tan(PI*60.0 / 360.0), width/2.0, height/2.0, 0, 0, 1, 0);
 
  fft.forward(stream.mix);

  stroke(0, 255, 0, 128);
  
  for(int i = 0; i < fft.specSize(); i=i+1)
  {
    line(i+150, height/2-(fft.getBand(i)*5), i+1+150, height/2-((fft.getBand(i+1)*5)));
  }

}

void stop()
{
  stream.close();
  super.stop();
}

thanks for help

NoisyVysioN

taifunbrowser

Re: 3D spectrum analyzer
Reply #1 - Dec 17^th, 2007, 4:10am

I use LinkedList's heavily in my code,

so... Type is your class defining 1 spectrum line.
Code:


LinkedList<Type> b = new LinkedList();
//I know its complex, but I like to "reverse" my lists.
Adding an element:
b.add(element) //adds to end of list
if (b.size()>MAXIMUMZ)
    b.poll(); //remove first element.

//Drawing loop:
pushMatrix();
translate(0,0,z)//Move to the farthest away line
for(Iterator<Type> itr = b.iterator(b.size()); itr.hasPrevious(); ){
    itr.previous().draw(this); //object oriented method.
    translate(0,0,-1) // move towards screen
}
popMatrix();

If you haven't looked into setting your camera angle, you'll have to do that too if you want the stuff to turn out right...

of course, its very simple if you want to draw from you goin away too.

subzero YaBB Newbies Offline Posts: 5	Re: 3D spectrum analyzer Reply #2 - Dec 17^th, 2007, 8:54am thanks taifun, but i fear your solution is too advanced for me. maybe a simple array of objects is enough, but i need a tutorial on class programming because it's not clear for me. if you know a tutorial about classes or linked lists please let me know
	NoisyVysioN

taifunbrowser

Re: 3D spectrum analyzer
Reply #3 - Dec 17^th, 2007, 2:38pm

idea!

Code:


private int modCount = 0;
private FFTLine[] spectralDisplay = new FFTLine[65];//change
public void addLine(FFTLine lin){
     spectralDisplay[modCount]=lin;
     modCount = (modCount+1)%spectralDisplay.length;
} 
public void drawLines(){
   //modCount becomes the "front" of directional array
   pushMatrix();
   translate(0,0,-z);//Go to end/ front of line
   for(int itr = 0; itr < spectralDisplay.length; itr++){
	 int actual = (modCount+itr)%spectralDisplay.length;
	 if (spectralDisplay[actual]!=null){
		 spectralDisplay[actual].draw();
	 }
	 translate(0,0,1);//move for next line.
   }
   popMatrix();
}

so, this should cause newly added lines to be drawn first...

tomgupper

Re: 3D spectrum analyzer
Reply #4 - Feb 12^th, 2008, 3:47pm

I did something similar to this last year...

Essentially I had a spectrum object, which calculated and drew the line from the FFT values. This object was then saved, and added to a list of spectrum objects. It would then move back and fade out. Essentially it was a particle system, but the particles were automatically generated spectrum lines.

I got an effect similar to this :
http://www.tenfiftyfour.com/aAVis/wp-content/uploads/2007/09/woo.PNG
example file here : http://www.tenfiftyfour.com/aAVis/processing/motionblur_test/applicationwindows.rar
or
http://www.tenfiftyfour.com/aAVis/processing/motionblur_test/applicationmacosx.rar for mac users

That the sort of thing you're after ? Will try and dig up the source code if so.

subzero YaBB Newbies Offline Posts: 5	Re: 3D spectrum analyzer Reply #5 - Feb 19^th, 2008, 1:32am yes it's exactly what i tried to do sadly i have not much time at the moment to work on it, but i'd like to study your code. thanks!
	NoisyVysioN

tomgupper YaBB Newbies Offline Posts: 46 Australia	Re: 3D spectrum analyzer Reply #6 - Feb 19^th, 2008, 1:06pm http://tenfiftyfour.com/Processing/SpecAnalysis3D.rar There ya go. I'm sure there's a much better way to go about it - and I apologise if the code is a bit difficult to follow, Sort of a Frankenstien program this one, lots of little bits I added on to form the full monster. Hope it helps.

Re: 3D spectrum analyzer
Reply #7 - Feb 19^th, 2008, 3:10pm

hi

i also did a 3d audio spectrum. this version is more intuitive to code, but less optimized. instead of array copying, a simple head location with modolus should be much faster. in this version, the incoming interpolated fft values are always put in array pos[0] and after a simple copy like array[n] = array[n-1] cycles all lists through the 3d array.

here's my applet and src : http://www.s373.net/x/audiosp3ctrum_applet

a

subzero YaBB Newbies Offline Posts: 5	Re: 3D spectrum analyzer Reply #8 - Feb 23^rd, 2008, 1:08pm really thanks to both, i'll study your codes and post here if i come out with something cool
	NoisyVysioN

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