I'm wanting to develop a prototype for the following demonstration in processing.

It would involve blowing into a speaker which picks up noise, creating a visualization of white mist
on a black background. The sort of look when you mist up a window using your breath on a cold winters day.

I would then like to be able to draw on this white mist. clearing or erasing the white (where a finger has been) so one can write a message in it.

I know I might have to use processing and minim to complete this.

But just needed help direct me in a more specific direction.

Here is the code I have so far, but would need it to be sound activated and to be able to draw over the white mist!:

void setup(){
  background(0);
  size(400, 400);
  noStroke();
  smooth();
}

void draw(){

  if(frameCount % 20 == 0){
    fill(0, 5);
    rect(0, 0, width, height);
    filter(BLUR, 1.0);
  }
 
  if (mousePressed && mouseButton == LEFT){
    fill(255, 5);
    int r = int(random(50, 200));
    int x = mouseX + int(random(-10, 10));
    int y = mouseY + int(random(-10, 10));
    ellipse(x, y, r, r);
  }
  else if (mousePressed && mouseButton == RIGHT){
    fill(0);
    ellipse(mouseX, mouseY, 10, 10);
  }
}