code: function getLab(color) {
      var xyz = getXYZ(color);
  
      var white = [ 95.047, 100.000, 108.883 ]; //for X, Y, Z
  
      var x = fromXYZValueToLabValue(xyz[0], white[0]);
      var y = fromXYZValueToLabValue(xyz[1], white[1]);
      var z = fromXYZValueToLabValue(xyz[2], white[2]);
  
      return [
          116 * y - 16,
          500 * (x - y),
          200 * (y - z)
      ]
  }
docs: Returns LAB color components
  @param  {Array} color - RGBA color array [r,g,b,a]
  @return {Array}       - LAB values array [l,a,b] (l:0..100, a:-128..127, b:-128..127)