You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: iimg_multi_threshold.m
    path of file: ./repos/CanlabCore/CanlabCore/Index_image_manip_tools
    
    the code of the file until where you have to start completion: function [cl, dat, cl_extent, dat_extent] = iimg_multi_threshold(inname, varargin)
% :Usage:
% ::
%
%     [cl, dat, cl_ext
    
function dat_extent = get_extent_regions(inname, pruneseed, lowest_thresh, szthresh, volInfo, mask)
if lowest_thresh >= 0
    dat = iimg_threshold(inname, 'thr', lowest_thresh, 'k', szthresh, 'volInfo', volInfo, 'mask', mask);
else
    % negative threshold; invalid for p-maps
    dat = iimg_threshold(inname, 'thr', [-Inf lowest_thresh(1)], 'k', szthresh, 'volInfo', volInfo, 'mask', mask);    
end