ABSTRACT
Conservation, readability, and content analysis of ancient documents are often compromised by several and different damages that they have undertaken over time, and that continue to cause a progressive decay. Natural aging, usage, poor storage conditions, humidity, molds, insect infestations, and fires are the most diffuse degradation factors. In addition, the materials used in the original production of the documents, that is, paper or parchment and inks, are usually highly variable in consistency and characteristics. All these factors concur to cause ink diffusion and fading, seeping of ink from the reverse side (bleed-through distortion), transparency from either the reverse side or from subsequent pages (show-through distortion), stains, noise, low contrast, unfocused, faint, fragmented, or joined characters. Furthermore, these defects are usually varying across the document. These problems are common to the majority of governmental, historical, ecclesiastic and commercial archives
in Europe, so that seeking a remedy would have an enormous social and technological impact. Digital imaging can play a fundamental role in this respect. Indeed, it is an essential tool for generating digital archives, in order to ensure the documents’ accessibility and conservation, especially for those rare or very important historical documents, whose fragility prevents direct access by scholars and historians. Moreover, OCR (optical character recognition) processing for automatic transcription and indexing facilitates access to digital archives and the retrieval of information. Finally, a very common need is the improvement of the readability by interested scholars.
