def rotate_hue(image, hue_angle):
hue_rad = math.radians(hue_angle)
img_dkl = colour_spaces.rgb2dkl01(image) - 0.5
output = colour_spaces.dkl012rgb01(rotation(img_dkl, hue_rad) + 0.5,
raw=True)
if hue_angle == 90:
minvs = [-0.15963513, -0.24257698, -0.61854306]
maxvs = [+1.15951755, +1.24262220, +1.61844135]
elif hue_angle == 270:
minvs = [-0.90117482, 0.00000000, -0.17976814]
maxvs = [+1.90109239, 1.00001458, +1.17986642]
if hue_angle in [90, 270]:
for i in range(3):
output[:, :, i] = normalisations.min_max_normalise(output[:, :, i],
minv=minvs[i],
maxv=maxvs[i])
output = normalisations.clip01(output)
return output
def hsv012rgb01(x):
x = x.copy()
x[:, :, 0] *= 360
x = cv2.cvtColor(x.astype('float32'), cv2.COLOR_HSV2RGB)
return normalisations.clip01(x)
def dkl2rgb01(x, raw=False):
x = np.dot(x, rgb_from_dkl)
if raw:
return x
return normalisations.clip01(x)
def yog2rgb01(x):
x = np.dot(x, rgb_from_yog)
return normalisations.clip01(x)
def xyz2rgb01(x):
x = np.dot(x, rgb_from_xyz)
return normalisations.clip01(x)