How to add colormap on an image?

Add colormap on a .png/.jpeg image.

[Rik]

A colormap only has meaning for indexed images. Are your image actually indexed? And what have you tried?

Answer 1

[Constantino Carlos Reyes-Aldasoro]

I guess that this is a 2 step question, you want to add a colormap and then export as a png or jpeg, try the following, read an image, display and change colormap

a=imread('moon.tif');
imagesc(a)
colormap(autumn)

Now you can export as any format you want:

print('-dpng','-r100','myImage.png')

Answer 2

[Rik]

In case you don't want to make a screenshot of your image with print, you can use ind2rgb:

a=imread('moon.tif');
map=colormap(autumn);
b=ind2rgb(a,map);
imshow(b)

Now you can use imwrite to write this RGB image to a file.