Using Quaternion Fourier Transform in Steganography Systems

Abstract

steganography is the discipline of exchanging information messages in such way that no one, other than the intended recipient, suspects the existence of the message.  The transmitted message can be in textual or multimedia form (audio, image or video) and can be hidden within cover media. Moreover, the hidden message can be in either plain or cipher form.  In steganography, the majority of hiding techniques are implemented either in spatial domain or in frequency domain of the cover media.   The current contribution introduces a new a steganography technique for hiding a textual message within a cover image.   Both the message and the cover image is converted to quaternion form and then only the quaternion message is converted to the frequency domain using Quaternion Fast Fourier Discrete Transform (QFFDT) technique.  Simple quaternion mathematics are used to combine the message (in quaternion frequency domain) within the cover image (in quaternion form).  Conversely, the hidden message can be revealed at the receiver using simple quaternion mathematics in presence of the original cover image.  The proposed method allows hiding a huge amount of data and it is much complicated against steganalysis compared to the traditional methods. The method is assessed using the known performance metrics and the obtained results show that it is robust and more secure against steganalysis attacks without affecting the consumed bandwidth of the communication channel.