Create a Colored Image from a Gray Image

Question

I am new here and I need some help.

I have a gray image, and I need to colour it using Python.

This is the kind of images I have:

And I need to transform it to be like the images that can be plot by using matplotlib ColorMap "CMRmap" like this one and save it:

Thank you in advance for helping me.

Welcome to stack overflow! Unfortunately we are not a code writing service, and we ask, at the minimum, that you show some code for what you've tried based on your own research, and what went wrong with your attempts — G. Anderson, Jul 18 '19 at 15:16
you don't need to transform the image, just display it with the correct colormap — Miki, Jul 18 '19 at 15:51
Use matplotlib.pyplot to display your image. It will color code automatically or you can select other color tables or create your own. — fmw42, Jul 18 '19 at 16:40
Actually i need to save the images, i already know how to display it this way. — Wassim Bouatay, Jul 19 '19 at 08:48
This should help... https://stackoverflow.com/a/31546410/2836621 — Mark Setchell, Jul 19 '19 at 09:16

score 2 · Accepted Answer · answered Jul 19 '19 at 10:09

2

Sounds like you've figured out the colormap part, but not the saving. Building on Shawn's answer, if you want to save the figure, make a call to plt.savefig() instead of plt.show(). Then pass the path you want to save it to as an argument.

import cv2
import matplotlib.pyplot as plt

img = cv2.imread(r"path\to\img", 0)
plt.imshow(img, cmap='CMRmap')
plt.savefig("\path\to\output\file")

Hope this helps!

answered Jul 19 '19 at 10:09

Dominic McLoughlin

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Hi Wassim - if it solves your problem, then could you mark it as the accepted solution? Thanks. – Dominic McLoughlin Jul 20 '19 at 10:39
Hi Dominic, i just as add [solved] to the title or is there another way to do so ? – Wassim Bouatay Jul 21 '19 at 10:12
There should be a greyed-out tick under the up/downvote buttons. If you click it to accept the solution it goes green! – Dominic McLoughlin Jul 21 '19 at 14:36

Shawn Mathew · Answer 2 · 2019-07-19T14:40:39.727

1

Expanding on @Miki's comment, you simply need to use a colormap. The colored image shows the CMRmap colormap.

import cv2
import matplotlib.pyplot as plt

img = cv2.imread(r"path\to\img", 0)
plt.imshow(img, cmap='CMRmap')
plt.plot()
plt.savefig('foo.png')

Output:

Matplotlib lists all the colormaps here

Edit: updated answer with OP's clarification.

edited Jul 19 '19 at 14:40

answered Jul 18 '19 at 16:19

Shawn Mathew

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Thank you, but i already did that, the problem is how to save the image. Sorry i wasn't clear enough in my question. – Wassim Bouatay Jul 19 '19 at 08:49

Create a Colored Image from a Gray Image

2 Answers2