Is there a way to use the Amplitude class to analyze audio data from external sources in real time?

Question

I am working on a project in Processing 3 where visuals are modulated by the amplitude of a song. However, I want to take it further. I would like to be able to play any song, or even have a band play in a mic'd room, and have my visuals respond while its playing. Right now, I have to tell the computer what song to use from the Sketch Folder but obviously that is not what I want to do.

The end goal is to project my visuals onto a wall in a club setting. To avoid picking up the crowd noise, I thought it would make sense to send the signal from the DJ booth to the computer(probably using an audio interface). I don't know if thats necessarily important for writing the code, but that is where my head is at. (Ik this might be a bit different from programming the aforementioned band idea...)

Anyway, if anyone has any good examples or information on how to do this, it would be greatly appreciated. I have attached a screenshot of my code right now. Eventually, I'll make the visuals more complex, but you get the point.

import processing.sound.*;

SoundFile sample;
Amplitude rms;

float smoothingFactor = 0.06;

float sum;

float x, y;
float xStep = 40;
float yStep = 200;
float a, a_;

int num = 400;

void setup(){
  size(1400,1000);
  
  sample = new SoundFile(this, "prettylights.mp3"); //to run code, load an audio file here
  sample.loop();
  rms = new Amplitude(this);
  rms.input(sample);
}

void draw(){
  background(20,20,30);
  strokeCap(CORNER);
  strokeWeight(xStep);
  
  sum += (rms.analyze() - sum) * smoothingFactor;
  
  float rms_scaled = sum * (height/2) * 3;
  
  int n=0;
  while (n<num) {
    stroke(255-255*cos(radians(a)),25,25,230-255*sin(radians(a)));
    line(x, y, x, y+yStep);
    //line(x, y,rms_scaled, rms_scaled);
    x+=xStep;
    if (x>width){
      x=xStep/2;
      y+=yStep;
    }
    if (y>=height){
      y=0;
      a=rms_scaled;
      //a=0;
    }
    n++;
    a+=a_;
  }
  a_+=0.1;
}

Answer 1

I figured it out! I just needed to use the AudioIn class.

import processing.sound.*;
AudioIn in;

void setup() {
  size(640, 360);
  background(255);
    
  // Create the Input stream
  in = new AudioIn(this, 0);
  in.play();
}      

void draw() {
}