Classification of the Hand-Printed and Printed Medieval Glagolitic Documents using Differentiation in Orthography

The angular Glagolitic documents dated from the XIII to XV century in the hand-printed form and from the XV up to XIX century in the printed form. During such a wide period of time, the way of writing documents was changed. It is particularly true for so-called old and new Glagolitic orthography. The old Glagolitic orthography was used in all documents whose origin is Croatia as well as when the editors were Croatians. This was spread in the period from the XIII to the first half of XIV century. After that period, under the influence of the Latin script, the Glagolitic orthography changed to so-called new one. The paper proposes a new automatic methodology for the classification and differentiation of the Glagolitic documents written by old and new orthography style. It consists of initial document transformation to coded text according to the horizontal energy levels in the text line. This coded text is then seen as an image. The image is subjected to the texture analysis in order to extract a feature vector. The extracted feature vector is used as an input to the classification tool. As a final result, the classification tool differentiates Glagolitic documents written in different orthography styles. The experiment is based on an excerpt of the original Glagolitic documents dated from the XIV to XIX century. The obtained results regarding differentiation of Glagolitic documents are very promising.