Digital color restoration for the preservation of reversal film heritage

During the last four decades of the 20th century, reversal films have been very popular in many parts of the world, being used for both educational and recreative purposes, even projected in many private homes. The Romanian Animafilm studios published throughout the decades an impressive collection of such films on various subjects, mostly animated stories, but also with historical or educational topics. Today, the existing film rolls are suffering from time decay, the obvious wear and tear from being projected so many times or simply stored, but also specific reversal-film preservation issues. The goal of our research is to investigate the possibilities of reversal film image digitization, color enhancement and digital restoration for the purpose of preserving its heritage and also increasing its content availability in the digital era. In this paper, we describe the digitization, color enhancement and digital restoration results obtained on degraded reversal films containing animated stories by proposing and applying a specific set of unsupervised, pipelined image processing tasks performing color cast removal and color correction. We present our experimental results, discussion and conclusions.