In this paper we present an algorithm for thresholding images of historical documents. The main objective is to generate high quality monochromatic images in order to make them easily accessible through the Internet. Our new algorithm is based on two definitions of entropy: Shannon's classical concept and a variation called Tsallis entropy. For historical documents, our method proved to be more efficient than several known thresholding algorithms by several measures.
Carlos A. B. Mello, Luciana A. Schuler