I read 3D volume whose size 240x240x155 and I want to read slice by slice and wants to apply feature extraction techniques on them How I can read one slice than other?

Hello Please, may you help me to read the 3D volume in MATLAB?

    v=niftiread('Brats17_2013_2_1_flair.nii.gz');
    figure, imshow(v(:,:,85),[]);
    %how to read slice#1 than slice#2 and so on

Answer 1

[Walter Roberson]

for slicenumber = 1 : size(v,3)
  this_slice = v(:,:,slicenumber);
  this_result = YourFeatureExtractionCallGoesHere(this_slice);
  all_results{slicenumber} = this_result;
end

Sometimes other data structures would be more appropriate than a cell array: it depends on what data type is returned by YourFeatureExtractionCallGoesHere

[leena]

@walter Roberson can we apply cat???

[Walter Roberson]

Yes, but it is unlikely that would be efficient if you are still building the data structure.

If you have a cell array in which the entries are all the same size, then you can use something like

cat(3, all_results{:})

to get a 3 dimensional array of the component parts.

But if that was your aim, then better would be to just store them in 3D in the first place:

numslices = size(v,3);
for slicenumber = 1 : numslices
  this_slice = v(:,:,slicenumber);
  this_result = YourFeatureExtractionCallGoesHere(this_slice);
  all_results(:,:,slicenumber) = this_result;
  if slicenumber == 1 && numslices ~= 1
    all_results(end,end,numslices) = 0;
  end
end

The if logic there takes the 2d array all_results of unknown size and extends it to have numslices panes in an efficient way

[Javaid Iqbal]

Thanks sir for sharing this solution :)