Thread Subject: Seeking Best Hyperspectral-Image Reshaping (Planer to pixel interleaved) for Speed

Questions:
1. Is there a better way?
2. Is there a faster way?

I am working on a hyperspectral image that is 4096x512 by 187 bands.

I'm doing classification, but it is very slow because every time I want to classify a pixel, I need to go to 187 places in memory.

I am thinking that I need to reshape the image so that all the band data is right next to each other in memory, and then transpose it...

Here is some simple code for a small matrix that shows what I think I need to do:

    mm = ones(2);
    mm(:,:,2) = ones(2)*2;
    mm(:,:,3) = ones(2)*3;
    mm(:,:,4) = ones(2)*4;
    
    dims = size(mm);
    mr = reshape(mm,dims(1)*dims(2),dims(3))'
    rm = reshape(mr,dims(2)*dims(3),dims(1))

This achieved the goal of putting the pixel bands together. However, it looks like a lot of work, and I have no idea what I'm doing to the computer memory.

Ideas for improvement welcomed.
Remember that the real image is much larger.

Thank you!