# how to calculate entropy of colored image?

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sweta arya on 29 Dec 2015
Commented: Jordan Rashid on 23 Oct 2018
how to calculate entropy of colored image?
Htet Yamin Ko Ko on 2 Jan 2017
You can calculate entropy for each color channel separately.

A. P. B. on 23 Jun 2017
Edited: A. P. B. on 23 Jun 2017
Assuming input_image is the name of the input. Entropy of each channel can be found using : Entropy_Red_Channel=Entropy(input_image(:,:,1)).
For each channel R,G and B you can calculate them separately. You can calculate entropy for multidimensional image but the function entropy will consider each of them as gray scale not RGB. Finally you can average the per channel entropy.

Jordan Rashid on 6 Sep 2018
Unless you account for the mutual information between channels, the solutions posted here will overestimate the total entropy.
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Jordan Rashid on 23 Oct 2018
https://en.wikipedia.org/wiki/Mutual_information#Relation_to_conditional_and_joint_entropy
The calculations include many more terms as you increase the number of channels.