We did our processing on the roborio this year. Primary reason is that it was powerful enough for what we needed to do. For the off season we're working on an on robot coprocessor to do the image processing for us.
Our robot code is on GitHub here under 2016-RoboBees-OffSeason:
https://github.com/FRC-836/
You WILL need the 836-Library to be installed in userlib. Documentation is spotty in many places and we're working to improve that. Message me if you have any questions. Also, those are works in progress as we go through the off season so there will be udpates.