Character segmentation from ancient palm leaf manuscripts in Thailand

Abstract

This paper presents a character segmentation system from ancient palm leaf manuscripts written in ancient Thai language. This aims to develop an automated system for the digitization and processing of ancient manuscripts. In this paper, the preprocessing stage of noise reduction is carried out. An optimal binarization is selected in order to reduce the unrelated noise and background information on the document. The proposed approach can improve the readability of the documents and enable selection of the optimal binarization technique. Text line segmentation is then applied to partial projection profiles, and the characters are separated by using the contour tracing algorithm and a trace of background skeleton. The experiment results have shown that this proposed system can be used to support subsequent steps such as automatic recognition of characters from Thai ancient palm leaf.

Enhancement and Segmentation Techniques for Palm-Leaf Manuscript Images

“…In literature review, Surinta, O. & Chamcong, R. [7][8] used Otsu"s algorithm, line segmentation and histogram method to segment the text from manuscitps. S. Phattarachairawee & M. Ketcham [9] transformed image to grayscale image, a contrast stretching and histogram equalization are used.…”

Image Segmentation of Historical Handwriting from Palm Leaf Manuscripts

“…The user can understand the system by utilizing an easy to use graphical user interface. [5] The system will display image results step by step. Fig.…”

“…This techniques for calculate the transformation to apply to each pixel in the image. The equation is: [5] …”

“…The background elimination method proposed by Otsu [5,8,9] has the advantage of not needing any prior knowledge of the image, based only on its grey level histogram. The main idea is to find in the histogram an optimal threshold that divides the image objects by constructing two classes from any arbitrary grey level, using the discriminated analysis shown in Fig.…”

“…For this reason, Mahasarakham University is establishing Palm Leaf Manuscript Preservation Project for the discovery, preservation and protection of palm leaf manuscripts from Northeast Thailand. [5] …”