immich/e2e/src/generators.ts

import { PNG } from 'pngjs';

const createPNG = (r: number, g: number, b: number) => {
  const image = new PNG({ width: 1, height: 1 });
  image.data[0] = r;
  image.data[1] = g;
  image.data[2] = b;
  image.data[3] = 255;
  return PNG.sync.write(image);
};

function* newPngFactory() {
  for (let r = 0; r < 255; r++) {
    for (let g = 0; g < 255; g++) {
      for (let b = 0; b < 255; b++) {
        yield createPNG(r, g, b);
      }
    }
  }
}

const pngFactory = newPngFactory();

export const makeRandomImage = () => {
  const { value } = pngFactory.next();
  if (!value) {
    throw new Error('Ran out of random asset data');
  }

  return value;
};