How to Combine Low and High Frequencies of Two Images in MATLAB? I would like to combine two images A and B in the following way:

1) I want to take a Fourier transform of both of them

2) For image A I want to apply a weighted filter, which gives more emphasis for low frequencies

3) For image B I want to apply a weighted filter, which gives more emphasis for high frequencies

4) I want to combine these frequencies and take the inverse Fourier transform

Can someone give me any guidelines where I should start (which functions etc.) to do this in Matlab? =) I'm kinda learning about Fourier transform and I want to play around with images. I was hoping if someone could give an example of code how this could be done etc.

Please note that I'm new at this stuff and I'm not very familiar with all the terminology yet. I'm an amateur trying to learn about Fourier transform by doing an experiment with it :) 

Thank you for any help! =)

P.S. I would appreciate if someone could give me a minimal code snippet showing me what I need to do =)
The easiest way doing so would be Laplacian Pyramid.

Yet, it can be done just by using simple Addition operator.
Just add the High Frequency of one image to the Low Frequency of the other.
Keep in mind few things:


Dimensions must be the same.
Otherwise, interpolate to the same dimensions.
It is better to use HPF which is built from the same LPF used.
To the least, they must have the same Cut Off Frequency.
Use floating point arithmetic for this procedure.