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{
% Starting stack: L, A, B
% /!\ WARNING: The A and B components **MUST** be encoded
% in the range [0, 1] before calling this function.
% This is because the function assumes that the
% A and B components are offset by a factor of 0.5
% in order to meet the range requirements of the
% PDF specification.
exch 0.5 sub
exch 0.5 sub
% Load L a and b into the stack
2 index
2 index
2 index
% Compute f1 = ((0.3963377774 * a) + (0.2158037573 * b) + L)^3
0.2158037573 mul exch
0.3963377774 mul add add
dup dup mul mul
% Load L, a, and b into the stack
3 index
3 index
3 index
% Compute f2 = ((-0.1055613458 * a) + (-0.0638541728 * b) + L)^3
-0.0638541728 mul exch
-0.1055613458 mul add add
dup dup mul mul
% Load L, a, and b into the stack
4 index
4 index
4 index
% Compute f3 = ((-0.0894841775 * a) + (-1.2914855480 * b) + L)^3
-1.2914855480 mul exch
-0.0894841775 mul add add
dup dup mul mul
% Discard L, a, and b by rolling the stack and popping
6 3 roll pop pop pop
% Load f1, f2, and f3 into the stack
2 index
2 index
2 index
% Compute R = f1 * 4.0767416621 + f2 * -3.3077115913 + f3 * 0.2309699292
0.2309699292 mul exch
-3.3077115913 mul add exch
4.0767416621 mul add
% Load f1, f2, and f3 into the stack
3 index
3 index
3 index
% Compute G = f1 * -1.2684380046 + f2 * 2.6097574011 + f3 * -0.3413193965
-0.3413193965 mul exch
2.6097574011 mul add exch
-1.2684380046 mul add
% Load f1, f2, and f3 into the stack
4 index
4 index
4 index
% Compute B = f1 * -0.0041960863 + f2 * -0.7034186147 + f3 * 1.7076147010
1.7076147010 mul exch
-0.7034186147 mul add exch
-0.0041960863 mul add
% Discard f1, f2, and f3 by rolling the stack and popping
6 3 roll pop pop pop
}
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