def lightfield(rgb):
(_,w,_) = rgb.shape
# color balance
cb = gray_world(rgb).clip(0.,1.)
# estimate background
rf = uniform_filter(cb,w/3)
# subtract it from image
sb = cb - rf
# rescale
sb = (sb - sb.min()) / sb.ptp()
# gamma, brightness
sb = np.power(sb,4./3.) * 2
# apply unsharp mask
s = 3
um = gaussian_filter(sb,10)
sharp = ((s / (s - 1)) * (sb - um / s)).clip(0.,1.)
return sharp
def correct_image(self,image):
"""
Correct an RGB image.
Parameters
----------
image : ndarray
3-channel color (RGB) image
Returns
-------
corrected image : ndarray
corrected image (corrected for illumination and/or color balance and/or brightness.
does not clip out of gamut colors.
"""
if self.color_balance:
new_rgb = gray_world(image)
else:
new_rgb = image
return (new_rgb / self.lightmap) * self.lightmap.ptp() * self.brightness
