openMP

@divyanshu_grover, I know it's not a solution, but I recommend you to use Visual Studio 2015 (I guess it's free) and oF0.9.0 rc. I have used Visual Studio with OpenMP and works well. You just need to add /openmp flag, include omp.h and add pragmas:
https://msdn.microsoft.com/en-us/library/fw509c3b.aspx

FYI: OpenCV itself has a CUDA support but I never tried it (nor with oF).