Enhancement of Historical Document Images by Combining Global and Local Binarization Technique

Abstract

In this paper we present a combined binarization technique for historical document images. Usually, many binarization techniques are implemented in the literature for different types of binarization problems. The few simple available thresholding methods cannot be applied to many binarization problems. In order to improve the quality of historical document images, we propose a combined approach based on global and local thresholding methods. The method was evaluated on the benchmarking dataset used in the Handwritten Document Image Binarization Contest (H-DIBCO 2012) and an Arabic historical document from National Library of Algeria. The evaluation based on the word spotting system showed the efficiently of our approach. ink. In order to improve the quality of binarized image, we propose to enhance them before the binarization. The proposed method makes use of the global thresholding to enhance the document image, and then we apply a local thresholding method. This paper is structured as follow; Section II reviews the state of the art of binarization techniques. Our proposed method is presented in Section III. Then, experimental results are reported in Section IV. Finally, conclusion and future work are presented in Section V.