Can you edit a pcolor plot after generating one?

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Hopefully an easy question here. I am using pcolor's interpolation option to give me a map of a fourier transform (FT) of an NxN matrix of values.
N is chosen to be even, so interpolation fills in the coordinates in the dead center of the plot with the surrounding points (so for N=2 the center of the plot would be an interpolation between the 4 inputs of the matrix). I want to subtract out the center since this will be very high in magnitude, but I do not have this explicit value before hand.
Is there a way to apply a high pass filter to a FT before plotting it, or can I obtain a set of data points from pcolor which allows me to get rid of the central bit. Any other suggestion would work too!
If you'd like a plot, let me know too. I think the issue should be reasonably clear here though. Thanks!
dpb on 23 Feb 2020
Don't attach a .fig; use "SaveAs" and (say) pick .jpg and attach the resulting image file.
We really can't do much seriously w/o at least the code to look at of what you've done and if you have expectations of real feedback, attach the .mat file with the data so somebody can do something with it other than just look.
Did you do as suggested and remove mean from the input before FT?

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Accepted Answer

Walter Roberson
Walter Roberson on 23 Feb 2020
conv2() your 2d matrix with ones(2,2)/4 and use the option 'valid' on the call. Now access the center element of that matrix and subtract it from the matrix. Now imagesc() the resulting matrix.

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