NON-LINEAR SWITCHED VIDEO FILTER FOR TELEVISION PICTURE NOISE REDUCTION

摘要

Temporally filtered video samples are formed as the sum of a previous frame output sample (P) and a nonlinear function of the difference between current (S) and previous (P) samples. The function is nonlinear only for absolute values of differences less that 50 % (preferably 10 %) of the maximum range of the difference, and a smaller lookup table is used for implementing the nonlinear function than would otherwise be the case.