Almost invisible Latin and Greek inscriptions were discovered on the shroud of Turin around the image of the face. This result was obtained by using digital image processing techniques. An original method is developed to eliminate the texture of the cloth and also to combine data from different photographs or from the same plate digitized under various conditions. According to some paleographists, the revealed characters are thought to date back to before the Middle Ages. This conclusion could be a new argument in favor of the authenticity of the shroud.