Restoration of Double-Sided Ancient Music Documents with Bleed-Through

Abstract

Access to collections of cultural heritage is increasingly becoming a topic of interest for institutions like libraries. With the easy access to information provided by technologies such as the Internet, new ways exist for consulting ancient documents without exposing them to more dangers of degradation. One of those types of documents is written ancient music. These documents suffer from multiple kinds of degradation, where bleed-through outstands as the most damaging. This paper proposes a new method based on the Takagi Sugeno fuzzy classification algorithm to classify the pixels as bleed-through, after performing a general background restoration. This method is applied to a set of doublesided ancient music documents, and the obtained results compared with methods present in the literature.

A Non-parametric Framework for Document Bleed-through Removal

“…Some non-blind methods use comparative intensity information from both sides to improve the performance of well known binarisation algorithms. For example the Kullback-Leibler thresholding algorithm and the binarisation algorithm of Gatos et al [6] are improved for bleedthrough interference by adding in secondary threshold levels in [1], and the Sauvola and Pietikainen adaptive binarisation algorithm [14], improved by fuzzy classification, is used in [2]. The ICA method is extended to doublesided documents in [18], using the recto and verso images as the sources for a blind-source separation.…”

A Ground Truth Bleed-Through Document Image Database

“…1 ISOS is a project of the School of Celtic Studies, Dublin Institute for Advanced Studies, Dublin, Ireland, and is funded by the Dublin Institute for Advanced Studies. 2 The object of ISOS is to create digital images of manuscripts written in Irish, and to make these images accessible as an electronic resource for researchers.…”

“…Many non-blind methods use comparative intensity information from both sides to improve the performance of thresholding and segmentation algorithms. For example Sauvola's adaptive thresholding algorithm [12] followed by fuzzy classification is used in [2], the Kullback-Leibler (KL) thresholding algorithm and the binarisation algorithm of Gatos et al [6] are extended by adding in second threshold levels for the bleed-through interference in [1], and ICA is extended to double-sided documents in [16], using the recto and the flipped verso images as the sources. A model based approach is used in [9], where a function of the difference in intensities between the two sides is used to locate bleed-through regions.…”

“…Secondly, for all document restoration techniques, problems arise when trying to analyse results quantitatively, as there is no actual ground truth available. This problem may be overcome either by creating synthetic degraded images with known ground truth, [5], [16], or by creating synthetic ground truth data for given real degraded images, [2]. Alternatively, performance may be evaluated without any ground truth by quantifying how the restoration affects a secondary step, such as the performance of an Optical Character Recognition (OCR) system on the document image, [17], [16].…”

Manuscript Bleed-through Removal via Hysteresis Thresholding

“…Examples of nonblind approaches include wavelet analysis [12], symmetric orthogonalization [13], and intensity difference classification [4][5] [15]. Also, there has been some non-blind work focused specifically on ancient music documents [3] [1].…”