udg.js

const udg = 'https://upload.wikimedia.org/wikipedia/commons/thumb/5/5f/Escudo_UdeG.svg/1200px-Escudo_UdeG.svg.png'
let img = document.createElement('img');
let canvas = document.createElement('canvas');
let pixels = []

img.onload = function() {
  canvas.width = img.width/4;
  canvas.height = img.height/4;
  canvas.getContext('2d').drawImage(img, 0, 0, img.width / 4, img.height / 4);
  pixels = canvas.getContext('2d').getImageData(0, 0, img.width / 4, img.height / 4).data;
}

img.src = udg;

let strs = [];
let p = pixels
for (let i = 0; i < pixels.length; i += 4) {
  const x = ( i / 4) % 300;
  const y = ((i / 4) - x) / 300;

  const c = `rgba(${p[i+0]}, ${p[i+1]}, ${p[i+2]}, ${p[i+3] / 255})`;
  const o = `${c} ${x}px ${y}px`;
  strs.push(o)
  console.log(o);
}
let file = strs.join(',\n')

function download(filename, text) {
  var element = document.createElement('a');
  element.setAttribute('href', 'data:text/plain;charset=utf-8,' + encodeURIComponent(text));
  element.setAttribute('download', filename);

  element.style.display = 'none';
  document.body.appendChild(element);

  element.click();

  document.body.removeChild(element);
}

download('udg.txt', file)