Thank you for your reply.
There is a reason I'm trying to make Image::Base load the jpeg and not Gtk2.
Displaying several thumbnails on a canvas is very slow with the image loading abilities of Gtk2.
Image::Base has GTk2 parts and Imlib2 parts, so I thought they would offer some kind of connection between them.

Perhaps it would be better to just use the Imlib2-module with the Gtk-module?
I don't know. The Image::Base part may be unnecessary or even a bad idea.

Greetings