Noise reduction

Abstract

The invention provides noise filtering (3) of a signal (x) by estimating (30) a type of noise in the signal (x) and enabling (30) one of at least two noise filters (310,311,312), the enabled noise filter (310,311,312) being a most suitable filter for the estimated type of noise. An approximation of the noise (z) in the signal (x) is obtained by computing (302) a difference between the signal (x) and a noise-filtered (301) version of the signal (x). The invention uses (303) a kurtosis of the noise as a metric for estimating the type of noise. If the estimated type of noise is long-tailed noise, a median filter (312) is enabled to filter the signal. If the estimated type of noise is Gaussian noise or contaminated Gaussian noise, a spatio-temporal filter (310,311) is enabled to filter the signal. The invention may be applied in a video system (1) with a camera (2) and a noise filter (3).

Dependencies are inferred from the claim text.