def to_xyz100(self, lab):
L_R, a_R, b_R = lab
y_ref_s = L_R / 100
x_ref_s = a_R / 430 + y_ref_s
z_ref_s = y_ref_s - b_R / 170
xyz_ref = np.array([x_ref_s, y_ref_s, z_ref_s]) ** (1.0 / self.sigma)
return npx.solve(self.M, (npx.solve(self.R, xyz_ref).T / self.a_lms).T)
def to_rec2100(self, ictcp):
lms_ = npx.solve(self.M2, ictcp)
t = lms_**(1 / self.m2) - self.c1
# This next line is part of the model, but really it shouldn't occur for sane
# input data.
# t[t < 0] = 0.0
lms = (t / (self.c2 - self.c3 * lms_**(1 / self.m2)))**(1 / self.m1)
rgb = npx.solve(self.M1, lms)
return rgb
def to_xyz100(self, jzazbz):
jz, az, bz = jzazbz
iz = (jz + self.d0) / (1 + self.d - self.d * (jz + self.d0))
lms_ = npx.solve(self.M2, np.array([iz, az, bz]))
if np.any(lms_ < 0.0):
raise ColorioError("Illegal LMS value.")
lms = 10000 * ((self.c1 - lms_**(1 / self.p)) /
(self.c3 * lms_**(1 / self.p) - self.c2))**(1 / self.n)
x_, y_, z_ = npx.solve(self.M1, lms)
x = (x_ + (self.b - 1) * z_) / self.b
y = (y_ + (self.g - 1) * x) / self.g
# return (np.array([x, y, z_]).T * self.whitepoint).T
return np.array([x, y, z_])
def from_xyz100(self, xyz100):
# TODO NaN the values smaller than 0 and larger than 1
return npx.solve(self.invM, np.asarray(xyz100) / 100)
def to_xyz100(self, ipt):
lms_ = npx.solve(self.M2, ipt)
lms = np.sign(lms_) * np.abs(lms_)**(1 / 0.43)
return npx.solve(self.M1, lms)
def from_xyz100(self, xyz):
# https://en.wikipedia.org/wiki/SRGB#The_forward_transformation_(CIE_XYZ_to_sRGB)
# http://www.color.org/srgb.pdf
# TODO NaN the values smaller than 0 and larger than 1
return npx.solve(self.invM, xyz / 100)