How can I isolate the phase or amplitude of vertical spatial frequencies in an image?

Hello all,

I’m trying to process an image and output three different variations:

1. phase scrambled in 1-dimension
FFT > Scramble vertical phase information of spatial frequencies > Invert FFT
“The phase of the vertical visual spatial frequencies in the image was then scrambled”

2. amplitude scrambled in 1-dimension
FFT > Scramble amplitude of vertical spatial frequencies > Invert FFT
“the amplitudes of the vertical visual spatial frequencies in the image were scrambled”

3. "whitened” mid-to-high spatial frequency
FFT >Apply average amplitude to all spatial frequencies > Invert FFT
"all amplitudes of visual spatial frequencies were made equal to the average amplitude in the image "

The purpose of doing this is for a research project. I understand I have to use the cv.dft() & cv.idft() functions but how would one be able to isolate the phase or amplitude of vertical spatial frequencies.

Any help/tips/tricks most apprecaited.