A Gaussian filter applies a convolution to an image with a Normal distribution. This has the effect of smoothing the image, rather like looking with your eyes screwed up. Increasing the standard deviation of the Normal distribution increases the level of smearing.
Used in Chap. 12: pages 165, 166, 170, 181
Used in glossary entries: Gaussian filter, Normal distribution, standard deviation
Gaussian filter with σ = 0.8