color.js

class Color {
  constructor (r, g, b) {
    this.r = r
    this.g = g
    this.b = b
  }

  toHex () {
    return [this.r, this.g, this.b].reduce(
      (a, b) => a + ('00' + b.toString(16)).slice(-2),
      '#'
    )
  }

  static fromUV (y, cb, cr) {
    const y_ = y * 219
    const cb_ = cb * 224 - 112
    const cr_ = cr * 224 - 112

    return new Color(
      1.164 * y_ + 1.793 * cr_,
      1.164 * y_ - 0.213 * cb_ - 0.533 * cr_,
      1.164 * y_ + 2.112 * cb_
    )
  }
}