Black and white - advanced

[Medium]

Too few infos. What type is "Luminosity" of, and how is IntToByte() implemented?

Also, it usually is a good idea to re-order your calculation, and go with floats as long as possible to avoid nasty early rounding errors:

Delphi-Quellcode:

var
  L: Byte;
  temp: Single;
  C, M, Y: Single;
  i: array[0..5] of Single; // the percentages
begin
  C := (Bits.G+Bits.B)/2;
  Y := (Bits.R+Bits.G)/2;
  M := (Bits.R+Bits.B)/2;
  temp := (Bits.R*i[0] + Bits.G*i[1] + Bits.B*i[2] + C*i[3] + M*i[4] + Y*i[5])/300; // division by 300 is your Input() method mangled in, and put as last step for the whole thingy
  L := Byte(Round(Max(0, Min(255, temp))));
end;

Clipping and rounding and divisions are usually placed best after additions and multiplications (>=1) took place, to minimize rounding and precision errors. The brain grease spent on reordering the formulas is well spent in these places, and in this case is really simple math.