Simple script that uses image manipulation to generate combined flags for multiple purposes.
Open the flagcombiner.php in a text editor of your choice and change the paths to the destination directories. Run it from you PHP activated webserver (e.g. XAMPP).
The original pictures i used are from here:
https://github.com/emcrisostomo/flags
This packet includes a windows batch-file that can convert the SVG files to resized PNGs by using an installment of Inkscape.