Computational Photography for Dust and Scratch Detection on Transparent Photographic Material

This work pertains the digital restoration of motion-picture films. — A new method for the automatic detection of blemishes on any kind of transparent photographic material (still and moving images, silver-based and dye-based material) is presented. It consists in an innovative combination of different optical techniques and computational photography. — The image layer is a random dispersion of microscopic elements (e.g. silver particles in b&w material) and its interaction with light is isotropic. Dust, scratches and other irregularities of the film surface produce shadows and reflections that are strongly dependent on the provenance of light. The acquisition of multiple images with different geometries of illumination, and the analysis of the differences between them, is found to be an effective method to emphasize irregularities in the film surface. — Moreover, the analysis with polarized light is found to improve the blemish detection. — The experiments show that the innovative method effectively detects flaws on photographic film surface.

Published

2012-10

Content type

Original Research

Keywords

Digital Restoration, Motion Picture, Computational Photography

DOI

10.5594/M001457

ISBN

978-1-61482-952-2