Application of image processing to aid revealing Mozart's hidden words

Abstract The letters of Wolfgang Mozart are of considerable interest in musicology, but some of these letters have certain words heavily crossed out. The aim of this pilot study was to investigate the application of digital image processing methods for examining deleted text in a letter by Wolfgang Mozart. The image processing methods used included image enhancement by adjustment of contrast and brightness. In order to help to identify deleted characters, we compared deleted with undeleted text in the letter. Grey-level slicing was also used in order to investigate the deletions further. The methods were found to be helpful in discerning lettering and analysing deletions. In conclusion, this study suggests that image processing methods can assist in the reading and interpretation of old manuscripts. The techniques appear to be of value in the investigation of obscured text and, in particular, when combined with comparison of undeleted text.