Sort field after images upload

I wonder how to set the ‘Sort’ field on image’s metadata.txt file after an images batch upload?
Currently, I have to manually reorder them for the field ‘Sort’ being written.
Thanks for any hint

According to what sort of criteria would you want to set the number of the sort field?

Edit: If the images are uploaded via the panel, you could use a panel hook (panel.file.upload).

That would based on their filename as the client followed a simple file naming scheme ( ascending figures ).
Okay for the panel hook, will try something simple.