Hi everyone,
You might want to check out our repository plugins which allow you to attribute images to the copyright holder (and also resizes the images to small, medium or large).
The code is based on the "Upload a file", "URL downloader" and "Flickr public" repositories.
The copyright information is added by appending the chosen license's icon, the copyright year, source URL and author name to the bottom of the image.
The size of the image is chosen via a dropdown menu at the upload stage with small, medium (standard) and large options.
The background and text colour of the appended copyright information can be chosen from a predefined list of options.
Here are the links to the plugin directory pages:
https://moodle.org/plugins/view/repository_xpert_flickr_public
https://moodle.org/plugins/view/repository_xpert_upload
https://moodle.org/plugins/view/repository_xpert_url
Thanks,
Barry