The printer Cannon Pixma MG2450 has drivers included in the package
The package is present in the sources and can be installed in Software Center. I have found this with Aaron‘s help under this discussion:
As for the integrated scanner, Simple Scan was not seeing the scanner the normal way, but only when run as root. That means there was no problem with the drivers.
It was a permissions problem, solved as indicated here: http://asksolus.com/question/scanning-works-only-with-root-privileges/.