Digital removal of blotches with variable semi-transparency using visibility laws

Abstract

This paper presents an automatic technique that removes blotches from archived photographs. In particular, we focus on blotches caused by water and dirt that cause a variable semi-transparency in the degraded region. The proposed digital removal consists of an automatic shrinking of the blotch that preserves the original image details. This operation is based on visibility laws in the wavelet domain. Preliminary experimental results show that the proposed model is also effective on critical blotches produced by dust and dirt. © 2007 Springer-Verlag Berlin Heidelberg.