Selective sharpness enhancement of heavily-corrupted old film sequences

The film material of old movies is often corrupted heavily by several distortions such as scratches, blotches and so on. In corrupted old film sequences, most of the sharp brightness transitions have been blurred, and picture details have come near to being lost. To improve their picture quality, we should restore sharpness of original brightness transitions. However, the application of the sharpness enhancement uniformly to the whole old film sequence would make such distortions as scratches and blotches more annoying. To solve this problem, this paper develops a selective sharpness enhancement method which can selectively sharpen blurred edges without increasing the visibility of those distortions such as scratches, blotches and random noise contained in corrupted old film sequences.