Detection and Restoration of Vertical Non-linear Scratches in Digitized Film Sequences

Vertical scratches are common artifacts in digitized film sequences. Conventional scratch restoration methods assume that vertical scratches are linear and cover the entire height of frame. Little has studied in regard to detecting vertical non-linear scratches and using temporal relation in two consecutive frames. The proposed method makes use of line-shaped templates and projections to detect vertical linear and non-linear scratches, and in-between frames to find the continuity of the vertical scratches in two consecutive frames. Weighted median filters are implemented to restore pixels damaged by the vertical scratches. Test results with Korean historic film sequence shows effective restoration of the vertical linear and non-linear scratches.