some circles in processing.

pulses.pde

Pulse[] pulses = new Pulse[48];

void setup() {
  size(640, 480);
  background(0);
  smooth();
  ellipseMode(CENTER);
  noFill();
  strokeWeight(20);  
  stroke(255,128);  
  
  for(int i = 0; i < pulses.length; i++) {
    float x = i * (width / pulses.length);
    float t = i * TWO_PI / pulses.length;
    pulses[i] = new Pulse(x, height/2.0, 100.0, 400.0, 0.0125, t);
  }
}

void draw() {
  background(0);
  for(int i = 0; i < pulses.length; i++) {
    pulses[i].update();
  }
}

class Pulse {
  float x, y, diameter, minDiameter, maxDiameter, dt, t;
  
  Pulse(float x, float y, float minDiameter, float maxDiameter, float dt, float t) {
    this.x = x;
    this.y = y;
    this.minDiameter = minDiameter;
    this.maxDiameter = maxDiameter;
    this.dt = dt;
    this.diameter = minDiameter;
    this.t = t;
  }
 
  void update() {    
    this.t += this.dt;
    this.diameter = ((sin(this.t) + 1.0) / 2.0) * (this.maxDiameter - this.minDiameter) + this.minDiameter;
    ellipse(this.x, this.y, this.diameter, this.diameter);
  } 
}