ImageMagick.Quantum.ScaleToDouble C# (CSharp) Метод

    internal static double ScaleToDouble(QuantumType value)
    {
      return (1.0 / Max) * value;
    }

 private ColorGray(IMagickColor <QuantumType> color)
     : base(color)
 {
     _shade =
         (0.212656 * Quantum.ScaleToDouble(color.R)) +
         (0.715158 * Quantum.ScaleToDouble(color.G)) +
         (0.072186 * Quantum.ScaleToDouble(color.B));
 }