collages

PImage[] img;
PImage mainImage;
int x, y;
int num=9, step = 1;

void setup() {
  size(960,960);
  mainImage = loadImage("main.jpg");
  img = new PImage[num];
  for (int i=1; i<num; i++) {
    img[i] = loadImage(i+".jpg");
  }
  rectMode(CENTER);
  for (int x=step/2; x<width; x+= step) {
    for (int y=step/2; y<height; y+= step) {
      search(x, y);
    }
  }
  //filter(GRAY);
}

void draw() {
}

void search(int x, int y) {
  color best = color(0);
  float cost = 360;
  color baseColor = mainImage.get(x, y); // 90
  for (int i=1; i<num; i++) {
    color candidate = img[i].get(x,y); // 40
    float diff = abs(brightness(baseColor)-brightness(candidate)); // 50
    if (diff < cost) {
      best = candidate;
      cost = diff;
    }
  }
  fill(best);
  //stroke(best);
  noStroke();
  rect(x, y, step, step);
}

void keyPressed() {
  if (key == 's') save(random(1234)+".jpg");
}