function preload() {
  icons = {};
  for (var name in emojis) {
    icons[name] = loadImage(emojisPath + '16x16/' + name + '.png');
  }
}
Pixel mapping, each pixel of a video input is translated into an emoji icon.
The pixel RGB value is mapped with the nearest (average) RGB value of an emoji.
Mapping via a [k-dimensional tree data structure](https://github.com/ubilabs/kd-tree-javascript).

KEYS
s                   : save png
f                   : start/stop recording of frames