Contrast Enhancement in Multispectral Images by Emphasizing Text Regions

Abstract

This paper deals with the enhancement of the readability in historic texts written on parchment. Due to mold, air humidity, water, etc. parchment and text are partially damaged and consequently hard to read. In order to enhance the readability of the text, the manuscript pages are imaged in different spectral bands ranging from 360 to 1000nm. The readability enhancement is based on a spectral and spatial analysis of the multivariate image data by Multivariate Spatial Correlation. The main advantage of the method is that especially the text regions are enhanced which is provided by generating a mask image. This mask is based on the automatic reconstruction of the ruling scheme of the text pages. The method is tested on two medieval Slavonic manuscripts written on parchment.

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Hyper-Hue and EMAP on Hyperspectral Images for Supervised Layer Decomposition of Old Master Drawings

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Higher order MRF for foreground-background separation in multi-spectral images of historical manuscripts

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