reduce_to_aspect_ratio.js

var maxpixels = [5472, 3648];

function reduce(numerator,denominator){
  var gcd = function gcd(a,b){
    return b ? gcd(b, a%b) : a;
  };
  gcd = gcd(numerator,denominator);
  return [numerator/gcd, denominator/gcd];
}

reduce(maxpixels[0],maxpixels[1]);