Urdu text steganography: Utilizing isolated letters

Abstract

This paper presents an imperceptible and high capacity feature based approach which hides a secret message into Urdu text cover media by utilising all isolated letters. Existing techniques are less imperceptible and also not robust against steganalysis attacks and some of these schemes are failed to provide the better capacity rates. Previous lexical based and syntax based schemes are ineffective to provide the better capacity rate and image based approaches are not robust against format attacks. Moreover, Feature based approaches are more perceptible and thus, cannot resist against visual attacks. This paper proposes an improved algorithm that encompasses all isolated letters of Urdu text for hiding data to provide better capacity rates. Furthermore, this technique is more secured by using strong public key encryption algorithm. In addition, scheme is also imperceptible, since it does not affect the external appearance of the text. Implementation shows that the proposed text steganography technique provides high concealing capacity.