Word spotting in archive documents using shape contexts

Abstract

The analysis of historical document images is not only interesting for the preservation of historical heritage but also for the extraction of semantic knowledge. In this paper we present a word spotting approach to find keyword images in digital archives. Detected words allow to construct metadata on document contents for indexing and retrieval purposes. Instead of using OCR based approches that would require accurate segmentation and high image quality, we propose a shape recognition method based on the well-known shape context descriptor. Our method is proven to be robust under hightly distorted and noisy document images, a usual drawback in old document analysis. It has been used in a real application scenario, the Collection of Border Records of the Girona Archive. In particular, spotted keywords are used to extract knowledge on personal data of people referred in the documents. © Springer-Verlag Berlin Heidelberg 2007.