RGB to HSV (Travis)
Given RGB values, find the max and min. V = max S = (max-min) / max If S = 0, H is undefined else R1 = (max-R) / (max-min) G1 = (max-G) / (max-min) G2 = (max-B) / (max-min) if R = max and G = min, H = 5 + B1 else if R = max and G not= min, H = 1 - G1 else if G = max and B = min, H = R1 + 1 else if G = max and B not=main, H = 3 - B1 else if R = max, H = 3 + G1 else H = 5 - R1 H = H*60 (converts to degrees so S and V lie between 0 and 1, H between 0 and 360)HSV to RGB (Travis)
Convert H degrees to a hexagon section hex = H / 360 main_colour = int(hex) sub_colour = hex - main_colour var1 = (1-S)*V var2 = (1 -(S * sub_colour)) * V var3 = (1 -(S * (1 - sub_colour))) * V then if main_colour = 0, R = V, G = var3, B = var1 main_colour = 1, R = var2, G = V, B = var1 main_colour = 2, R = var1, G = V, B = var3 main_colour = 3, R = var1, G = var2, B = V main_colour = 4, R = var3, G = var1, B = V main_colour = 5, R = V, G = var1, B = var2where int(x) converts x to an integer value.
(N.B. I haven't implemented this transform.)
RGB to HSV (Foley and VanDam)
max = maximum of RGB min = minimum of RGB V = max S = (max - min) / max if S = 0, H is undefined, else delta = max-min if R = max, H = (G-b)/delta if G = max, H = 2 + (B-R)/delta if B = max, H = 4 + (R-G)/delta H = H*60 if H < 0, H = H + 360HSV to RGB (Foley and VanDam)
if S = 0 and H = undefined, R = G = B = V if H = 360, H = 0 H = H / 60 i = floor(H) f = H - i p = V*(1-S) q = V*(1-(S*f)) t = V*(1 - (S * (1-f))) if i = 0, R = v, G = t, B = p if i = 1, R = q, G = v, B = p if i = 2, R = p, G = v, B = t if i = 3, R = p, G = q, B = v if i = 4, R = t, G = p, B = v if i = 5, R = v, G = p, B = qwhere floor is the C floor function.