STEGANOGRAPHY IN PERSIAN AND ARABIC UNICODE TEXTS USING PSEUDO-SPACE AND PSEUDO CONNECTION CHARACTERS

Sending information secretly and communicating covertly have been of great interest for ages. On the other hand, text documents have been widely used and consequently various methods for hiding information in texts (Text Steganography) have been developed so far. In this paper a new method is proposed for hiding information in Persian and Arabic Unicode texts. In Persian and Arabic, some letters are connected together in a word. But there are two characters, zero width non joiner (ZWNJ) and zero width joiner (ZWJ) characters, which are respectively prevents the Persian and Arabic letters from joining or forces them to join together. In this method by using these two special characters, the information is hidden in Persian and Arabic Unicode text documents. This method has a high hiding capacity because it hides one bit in each letter. Also this method does not make any apparent changes in the original text and have a perfect perceptual transparency.