How to apply gradient map on a grey scale image

Question

I've searched for any possible solution for that, but all the answers are not really clear or incomplete.

So, say I have the image uploaded into memory:

image = Image.open('image.jpg')

How do I apply this gradient (#582f91 to #00aeef):

To this image:

So it becomes this:

Thanks ahead.

Answer 1

Just use LinearSegmentedColormap :

# make a cmap
mycm=matplotlib.colors.LinearSegmentedColormap.from_list('',['#582f91', '#00aeef'])

# apply on a canal
imgrad=mycm(image[:,:,0])