Restoration of Old Film Sequences

Image flicker, undesirable fluctuations in image intensity not originating from the original scene, is a common artifact in old film sequences. After describing possible causes for image flicker this paper models the effects of flicker as local phenomena. Unfortunately estimation of the model parameters from the degraded sequence is hampered due to presence of noise, dirt and motion. In the latter case the model parameters can not be estimated directly from local data and are interpolated using the found model parameters of regions nearby. Once the model parameters have been estimated the film sequence can be corrected, taking care that no blocking artifacts occur. The application of this technique in combination with other restoration techniques is discussed.