1 procedure RgbToHsv(R, G, B: Byte; var H, S, V: Single);
2 var
3 mx, mn: Byte;
4 tmp: Single;
5 begin
6 mx := R;
7 mn := R;
8 if mx < G then mx := G;
9 if mx < B then mx := B;
10 if mn > G then mn := G;
11 if mn > B then mn := B;
12 if mx = 0 then
13 begin
14 H := -1; S := 0; V := 0;
15 Exit;
16 end;
17
18 V := mx / 255;
19 S := (mx - mn) / mx ;
20 tmp := 60.0 / (mx - mn);
21 if mx = R then H := (G - B) * tmp
22 else if mx = G then H := 120 + (B - R) * tmp
23 else if mx = B then H := 240 + (R - G) * tmp;
24 if H < 0 then H := H + 360;
25 end;
