The ISC International Journal of Information Security

Abstract Preserving data confidentiality is crucial in today’s digital world where data exchange is increasingly becoming digital. This paper presents a novel text steganography algorithm. Initially, the secret message is converted into a bit stream. This bit stream is then shuffled using a random sequence to enhance security. Finally, the data is converted into a specific ”time” (including date and hour), and this generated time is embedded within a suitable cover text. The results demonstrate that the proposed algorithm is robust against a variety of attacks, including retyping, OCR, printing and photocopying, compression, document feature modification, non-Unicode environment conversion, and semantic paraphrasing. The algorithm is language-independent and applicable to all languages. The scheme exhibits high transparency against visual and machine attacks and has a capacity of 18 bits per time. The embedding of information bits using a random sequence enhances the scheme’s resistance against detection attacks.

Abstract This paper investigates digital data hiding schemes. The concept of information hiding will be explained at first, and its traits, requirements, and applications will be described subsequently. In order to design a digital data hiding system, one should first become familiar with the concepts and criteria of information hiding. Having knowledge about the host signal, which may be audio, image, or video and the final receiver, which is Human Auditory System (HAS) or Human Visual System (HVS), is also beneficial. For the speech/audio case, HAS will be briefly reviewed to find out how to make the most of its weaknesses for embedding as much data as possible. The same discussion also holds for the image watermarking. Although several audio and image data hiding schemes have been proposed so far, they can be divided into a few categories. Hence, conventional schemes along with their recently published extensions are introduced. Besides, a general comparison is made among these methods leading researchers/designers to choose the appropriate schemes based on their applications. Regarding the old scenario of the prisoner-warden and the evil intention of the warden to eavesdrop and/or destroy the data that Alice sends to Bob, there are both intentional and unintentional attacks to digital information hiding systems, which have the same effect based on our definition. These attacks can also be considered for testing the performance or benchmarking, of the watermarking algorithm. They are also known as steganalysis methods which will be discussed at the end of the paper.