MATLAB: How to compute the mean of two disjoint region

image processingImage Processing Toolboxmean

Suppose I have to fragment of an image J : J_out_1 et J_out_2.

J_out_1 = J(1:h,startj:i);
J_out_2 = J(1:h,k:endj);

I would like to compute the mean of the union of those two regions , is it possible ?

m_out = mean2(J_out_1 union J_out_2);

Thank you in advance

Best Answer

m_out = mean([J_out_1(:); J_out_2(:)])

would be one way to do it assuming the image has only one colour channel. If they are RGB images:

m_out = mean([reshape(J_out_1, 1, [], 3), reshape(J_out_2, 1, [], 3)])

Note that if the two regions are the same size, you could just concatenate them without any reshaping (by colon or reshape).

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