I need to convert mutiple .nii files into one .nii.gz file.

In Matlab, I used gzip('*.nii'), but it creates multiple nii.gz files for each single nii file. How could I create one combined nii.gz file from many .nii files?

Thanks in advance

Answer 1

[Govind KM]

Hi Ed,

The “gzip” command is designed to compress individual files rather than creating a single archive containing multiple files. Hence a separate .gz file will be created for each .nii file.

A workaround to create a combined .gz file is to use the “tar” function along with “gzip”. The “tar” function combines multiple files together into a single .tar file, which can then be compressed using “gzip” :

%Concatenate all .nii files into a single .tar file
tar("MyTar","*.nii"); %Replace MyTar with the desired output file name
%Compress the .tar file with gzip
gzip("MyTar.tar");
%To get the compress files back, use gunzip and untar
gunzip("MyTar.tar.gz");
untar("MyTar.tar");

More details on the “tar” and “untar” functions can be found in the following documentation:

https://www.mathworks.com/help/matlab/ref/tar.html

https://www.mathworks.com/help/matlab/ref/untar.html

Hope this helps!