Functionality-Improved Arabic Text Steganography Based on Unicode Features

Steganography is the science of hiding secret messages in irrelevant data that is possibly of another form. Despite several Arabic text steganography techniques having been proposed in the literature, there is only a limited amount of research that shows high-quality steganography in terms of capacity and security. In this paper, we present a novel approach of hiding secret bits in Arabic text by using Unicode. Our method relies on the use of a contextual form of Arabic characters to hide certain secret bits. Extra characters, such as zero-width joiner, Kashida, and zero-width non-joiner, are also involved to further enhance the capacity while preserving security. Our experimental results show that the technique outperforms most reviewed existing methods in both capacity and security performance measures. Moreover, our technique can be widely adopted in any linked to Arabic characters, such as Urdu and Farsi as well as many languages benefiting from Unicode as the encoding standard possibly used for most of the world’s writing systems.