error: 'niftiread' undefined near line 21, column 21

[hbhutta]

I know that niftiread was released in Matlab version R2017b and it's a function in the core library. I am not familiar with Octave, all I know that is that Matlab files can be run in octave. Why I am I getting the above error?

function resize_nifti(input_dir, file_pattern)
    files_to_scale = dir(fullfile(input_dir, file_pattern));
    disp(files_to_scale);
    scale_factor = 2;

    path = fullfile(files_to_scale.folder, files_to_scale.name);
    disp(path);

    %  Originally scale_nifti function, put in here instead to have one function per file
    disp("Scaling NIFTI file");
    r = niftiread(path);
    r_s = imresize3(r, scale_factor);
    [path, name, ~] = fileparts(path);
    save_path = fullfile(path, strcat(name, "_scaled.nii"));
    disp(save_path);
    niftiwrite(r_s, save_path);
end

All the disp statements execute and everything works fine up to the line disp("Scaling NIFTI file"), as soon as the niftiread statement is reached I get the above error. Do I need to somehow "import" niftiread? I'm guessing not since it should be built in. Or maybe the octave version I am using does not correspond to at least Matlab version R2017b. Is this the case?

Any ideas would be appreciated.