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Zoom images into a column vector, sorted by row for each image

Hi dear Matlab specialists,

I have an array of images, say a 2 by 3 grid of images (6 images). Each image has a resolution of 4 x 4 (for simplicity). Suppose images have shades of gray.

I uploaded the images to a 4D matrix with dimensions of 2 x 3 x 4 x 4. Now I want to create a column vector with entries

1: first pixel of the first row in image 1.1

2: second pixel of the first row in image 1.1

3: ...

16: last pixel of the last row in image 1, 1

17: first pixel of the first row in image 2, 1

...

etc. There is a template. I could successfully create this using a bundle for loops:

for imageX = 1 : resolution(2)
   for imageY = 1 : resolution(1)
      for pixelX = 1 : resolution(4)
         for pixelY = 1 : resolution(3)

               % linear index for 4D indices
               row = ((imageY - 1) * resolution(2) + imageX - 1) * resolution(3) * resolution(4) + ...
                   (pixelY - 1) * resolution(4) + pixelX;

               lightFieldVector(row) = lightField(imageY, imageX, pixelY, pixelX);
         end
      end
   end
end

, reshape permute. , . , 2D-. , "", .

,

+4
1

-

lightFieldVector = reshape(permute(lightField,[4 3 2 1]),[],1)

linear indexing permute MATLAB.

-

R = resolution
lightField = permute(reshape(lightFieldVector,R(4),R(3),R(2),R(1)),[4 3 2 1])
+4

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