This project is inspired from MWPhotoBrowser and AirplayKit for iOS. You can find MWPhotoBrowser at https://github.com/mwaterfall/MWPhotoBrowser and you can find AirplayKit at https://github.com/rothacr/AirplayKit A mixture of airkit and mwphotobrowser. This allows you to play the image slideshow right to your apple tv.
Working: Its a pretty straight forward implementation. Download and run the project. Once the image shows up in full screen with the bottom menu, tap on the Organize button and it will display the image in the connected apple TV. The transition for the change of image is made as Reflections. You can always change them.
Reference: Airplay unofficial documentation can be found at http://nto.github.com/AirPlay.html You can follow this and edit whatever you like. I guess this can also be used for other media types.