Jerky Motion

[CCoug83]

Whenever I encode NTSC sources, mostly television shows, I end up with jerky motion compared to the film sources. I've encoded it as many ways as I can think of trying to correct this with little success, especially in panning scenes. I have managed to get it less jerky using AutoGK, but still not that great. Can anyone help me correct this problem?

[jggimi]

One possibility is that you are IVTCing sources which were true video sources rather than film transfers to video. Sporting events, news broadcasts, and the like. Sitcoms are usually shot on film and then transferred. Transferring 24fps film to 29.97fps video is done through Telecining.

NTSC is 29.97fps, but Telecined NTSC can be reduced to 23.976 by Inverse Telecining, either via Force FILM or via an IVTC filter set. But if the source wasn't originally Telecined, you should never Inverse Telecine.

Without knowing more about what the sources are, what your process is, and what you've been doing to try to solve it, I can only point you to our IVTC tutorial -- www.doom9.org/ivtc-tut.htm -- and hope that it either solves your trouble or gives you some ideas to further narrow down your problem (such as the with the dreaded film/video hybrids).

[CCoug83]

For these kinds of sources, I've mostly been using just AutoGK, which I believe is supposed to have an auto IVTC filter. I've only had limited success with it however, it does a better job than I do in GK, but still is nowhere near as smooth as the original DVD.