SVP when watching through tv tuner card?

Hi, anybody use svp when watching program through tv tuner/video capture card? I use kmplayer and seemed to have everything setup and working after  trial and error. However, is there an exact way to know if svp is working? SVP shows it is working although at first it kept skipping-picture until i made sure ffdshow had input and output of same colorspace-rgb24 for my card then it seemed okay. Anybody else try this? I know dvds work. By the way I watching through composite input.