A practical filtering method for film blotch removal based on local robust analysis of spatiotemporal brightness continuity

The film material of old movies is often corrupted by blotches which randomly happen in bursts. In this paper, we present a simple practical efficient method for the removal of such distortions. Most existing impulsive-noise-removal spatial filters such as a median filter do not work well in removing blotch distortions, because the approach of spatial filtering does not takes account of the first property about temporal discontinuity at all. This paper presents an advanced spatiotemporal fuzzy-filtering-based approach where we take the temporal-discontinuity property into consideration. We apply the presented method both to moving image sequences distorted by artificial blotches and to really corrupted old movies. Though simple, our presented method works very well, and achieves significant improvements on subjective picture quality