Cats
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Ben Bitdiddle took a photograph of his cat, but he only saved the associated DFT coefficients X[k_r, k_c], rather than saving the original image. However, he knows the original 77 \times 51 image looked like this:
Ben tries several different methods of recovering the original image based on X[k_r, k_c]. For each of the methods described below, indicate which of the images on the next page (labeled A-T) would have resulted from that approach. In these images, grey colors represent positive values (black represents 0, white represents 1), and red represents negative values (black represents 0, bright red represents -1). For all parts, assume that r=0, c=0 corresponds to the upper-left corner of the image (rows increase downward, and columns increase to the right).
Approaches
Question
Which image matches each process?
If an approach would have led to an image with nonzero imaginary components
(and thus would have resulted in a Python error when trying to save the image),
enter X for that approach.
