Hi,

This can be done easily in many photo and graphics applications, including the free Xtreme Photo Designer patch that you can download from the Magix website:

http://www.magix.com/uk/free-downloads/free-software/xtreme-photo-designer/

Just load your photo into the program and you will find rotate and flip commands in the "Image" menu. You can save your changes back to the file.

I hope this helps.