Imresize3 not resizing in z direction?

Hello,

I was using imresize on a stack of 54 images (each 2350 by 2350) forming a 3d array.

the pictures are binary. I also tried with grayscale.

I tried it like this:

stackresized = imresize3(stack, [NaN NaN 9 ]);

which crashed matlab.

I tried

stackresized = imresize3(stack, 0.2)

Which worked, but only in x and y directions. the number of slices remained the same.

Edit: I was mistaken, it used simply just one slice at a time from the array in the second example. When i feed it the whole array, the error is "Input image must have three dimensions but instead has 4 dimensions."

Which is strange because it is a grayscale 0-255, one colour channel of a RGB stack. should be 3 dimensional.

Can someone explain what I'm doing wrong here?

Thanks.

Answer 1

[Chris]

The second method should work. Are you sure you used imresize3() and not imresize() for that?

For the first method, input all three desired dimensions, even if they don't change from the original.

[Wasgeht Siedasan]

Yes i think you are right. I made a mistake, and it was reading them in as individual slices, so it only resized the xy coordinates.

When i use

stackresized = imresize3(stack, 0.2)

on the complete stack

it now says "Input image must have three dimensions but instead has 4 dimensions."

It should only have 3 dimensions however. It is the red channel extracted from an RGB using

stack = RGBstack(:, :, 1, :));

would it be possible to just resize the RGB stack? maybe with convn or something?

[Chris]

Try

squeeze(stack)

to remove the third (size 1) dimension. Or,

stack = squeeze(RGBstack(:,:,1,:));

[Wasgeht Siedasan]

works, thanks