HCL2RGB

This source code is for HCL to RGB color space conversion

This source code is based on the HCL color space equation which has been developed in the paper "A new perceptually uniform color space with associated color similarity measure for content-based image and video retrieval".

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function [r,g,b] = HCL2RGB(H,C,L,gamma)

if L==0

Q=1;

else

Q=exp((1-((3*C)/(4*L)))*(gamma/100));

end

Min = ((4*L)-(3*C))/(4*Q-2);

Max = Min + (3*C)/(2*Q);

if H>=0 && H<=pi/3

r=Max;

b=Min;

g=(r*tan(1.5*H)+b)/(1+tan(1.5*H));

elseif H>pi/3 && H<=2*pi/3

g=Max;

b=Min;

tamp=tan(0.75*(H - pi));

r=(g*(1+tamp)-b)/tamp;

elseif H>2*pi/3 && H<=pi

g=Max;

r=Min;

tamp=tan(0.75*(H - pi));

b=g*(1+tamp)-(r*tamp);

elseif H>=-pi/3 && H<0

r=Max;

g=Min;

tamp=tan(0.75*H);

b=g*(1+tamp)-(r*tamp);

elseif H>=-2*pi/3 && H<-pi/3

b=Max;

g=Min;

tamp=tan(0.75*H);

r=(g*(1+tamp)-b)/tamp;

else

b=Max;

r=Min;

tamp=tan(1.5*(H + pi));

g=(r*tamp + b)/(1+tamp);

end

end

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