Moodle change badges image size

when I create a badge in Moodle 3.5, the core automatically creates 3 thumbs for the badge icon (35x35, 100x100, 512x512). I should increase the size of the 100x100 thumb, but that size are hardcoded in the core package: /lib/gdlib.php, function process_new_icon() lines 184,214,228. What's the better way to achieve my purpose without hacking the core files? Maybe a local plugin would be able to override a core's function? Thanks