Algorithm for motion estimation

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Hy, now I'm working on a project that involving motion detection and direction of motion. I try the implemented functions in OpenCV and with pyramidal implementation of Lukas and Kanade's algorithm I was able to get really good results. But now the problem: Now I will have to write the same program for DSP and there is no way to use opencv and for that I will have to reimplement all of the needed functions... And the question:

Is LK the best algorithm for that use-case or there is better alternative ?