The Canopus cards were nice in the past for accelerated video encode/decode, but the more general purpose CUDA processing model, allows for all parts of the video processing to be handed off. That includes things like DNR, resizing, color correction, etc. It's only limited by the programmers of the software.
If course that means it has to be supported by the processing software, so review what program you plan to be using before committing to a particular hardware purchase. Although, if the software is still up in the air, I highly recommend looking for programs which do have CUDA support.
