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Steganography is a relatively new method for establishing hidden communication which gained attraction in recent years. Steganography is a method of hiding a secret message in a cover media such as image or text. In this paper a new method is proposed for steganography in English text by substituting the words which have different terms in British English and American English. © 2008 IEEE  

In this paper, a new method is proposed for motion vector steganalysis using the entropy value and its combination with the features of the optimized motion vector. In this method, the entropy of blocks is calculated to determine their texture and the precision of their motion vectors. Then, by using a fuzzy cluster, the blocks are clustered into the blocks with high and low texture, while the membership function of each block to a high texture class indicates the texture of that block. These membership functions are used to weight the effective features that are extracted by reconstructing the motion estimation equations. Characteristics of the results indicate that the use of entropy and... 

One of the methods introduced for establishing hidden communication is steganography. Steganography is the art of hiding information in a cover media without attracting attention. Text documents are one of the common cover media used for steganography in past. Steganography in text is more difficult than other media because there is a little redundant information in text documents. In this study, we propose a high capacity text steganography method. Our method can hide about 400 bits in each kilobyte of text. In Persian and Arabic, each letter can have four different shapes regarding to its position in the word. In this method this feature of Persian and Arabic languages is used for... 

Steganography is a method for hidden exchange of information by hiding data in a cover media such as image or sound. Text Steganography is one of the most difficult methods because a text file is not a proper media to hide data in it. In this paper we propose a new text Steganography method. In this method, we hide data in TeX documents. This method hides the data in places where there is a ligature such as "fi". © 2008 IEEE  

The aim of image steganography is to hide data in an image with visual and statistical invisibility. There have been a number of steganography techniques proposed over the past few years. In sequence, the development of these methods has led to an increased interest in steganalysis techniques. Most of the steganalysis methods attempt to estimate cover image statistics. One way to provide a secure steganography method is to disturb the estimation of steganalyzers. The main concern of this paper is to resist against steganalysis methods and utilize a mechanism to securely embed more secret data into an image. We present HYbrid steganographic approach (HYSA), which embeds secret data with... 

Sending information secretly and communicating covertly have been of great interest for ages. For this purpose, text documents have been widely used and, consequently, various methods for hiding information in texts (text steganography) have been developed so far. This paper deals with a new method to hide information in Persian (Farsi) and Arabic texts. In the Unicode Standard, there are two different characters for "Ya" and "Kaf". The two characters of and have the same shape but different codes if they are used at the beginning or in the middle of words. As a result, we can hide information in texts, considering the specified data to be hidden and using one of these two characters (for... 

This paper presents a new approach for hiding information in speech signals. In this method, the silence intervals of speech are found and the length (number of samples) of these intervals is changed to hide information. This method can be used simultaneously with other methods. © 2008 IEEE  

The problem of spreading secret data to embed into multiple cover images is called batch steganography and has been theoretically considered recently. Few works have been done in batch steganography, and in all of them, the payload is spread between cover images unwisely. We present the Adaptive batch steganography (ABS) approach and consider embedding capacity as a property of images. ABS is an approach to adaptively spread secret data among multiple cover images based on their embedding capacity. By splitting the payload based on image embedding capacity constraint, embedding can be done more secure than the state when the embedder does not know how much data can be hidden securely in an... 

Establishing Hidden Communication Is An Important Subject That Nowadays Has Gained Increasing Importance. Embedding A Secret Message Into A Cover Media Without Attracting Any Attention, Known As Steganography, Is One Of The Methods Used For Hidden Communication Purposes. In This Paper, We Present An Advanced Version Of "Collage Steganography" Method Which Is Robust Against Various Attacks. In This Method, An Image (For Example A View Of A Room) Is Created Which Contains Some Coded Information. This Method Is Robust Against Attacks Such As Adding Noise, Blurring And Jpeg Compression  

Recent studies in the field of text-steganography shows a promising future for linguistic driven stegosystems. One of the most common techniques in this field is known as lexical substitution which provides the requirements for security and payload capacity. However, the existing lexical substitution schemes need an enormous amount of shared data between sender and receiver which acts as the stego key. In this paper, we propose a novel encoding method to overcome this problem. Our proposed approach preserves the good properties of lexical substitution schemes while it provides short length stego keys and significant robustness against active adversary attacks. We demonstrate high efficiency... 

In this paper, we present a new adaptive contourlet-based steganography method that hides secret data in a specific or automatically selected cover image. Our proposed steganography method primarily decomposes the cover image by contourlet transform. Then, every bit of secret data is embedded by increasing or decreasing the value of one coefficient in a block of a contourlet subband. Contourlet coefficients are manipulated relative to their magnitudes to hide the secret data adaptively. In addition to proposing contourlet-based steganography method, this work investigates the effect of cover selection on steganography embedding and steganalysis results. We demonstrate, through the... 

This paper introduces a new method for the least significant bit (LSB) steganography in spatial domain. The new method, called one-third LSB embedding, reduces the probability of change per pixel to one-third without sacrificing the embedding capacity, as compared to previous LSB steganography techniques. This improvement results in a better imperceptibility and higher robustness against well known LSB detectors. Each bit of the message is carried through a function of three adjacent cover pixels and it is shown that no significant improvement is achieved by increasing the length of the pixel sequence employed. ©2009 IEEE  

Multi-layer schemes have been proposed for steganography. Also some authors have combined these methods with the idea of wet paper codes and gained higher embedding efficiency. This paper proposes a generalized multi-layer method for wet paper embedding. First, the cover bits are divided into blocks and, by combining these bits in groups of 3, a pyramid is formed. Next, the secret message is embedded through a layer-by-layer procedure. The proposed method has higher embedding efficiency in some cases and provides more flexibility for choosing the embedding payload, especially in lower payload conditions  

In this paper, a novel steganographic method is proposed which is based on the spatial domain: Least Significant Bit (LSB). The LSB matching method proposed by Mielikainen utilizes a binary function to reduce the number of changed pixel values. While in this paper a bipolar evaluating system is proposed to assess the performance of different orders for LSB matching. Afterward a genetic algorithm strategy is employed to search for an optimal solution among all the permutation orders. The experimental results show that by employing the proposed bipolar evaluating system, the distortion of the stego-image is reduced while the probability of detection is decreased  

The existing powerful steganalyzers can find out the presence of secret information in images with high accuracy. Increasing the embedding capacity of cover images reduces the detection risk of stego images. In this respect, we introduce boosted steganography scheme (BSS) that has a preprocessing stage before applying steganography methods. The goal of BSS is increasing the undetectability of stego images. Due to the dependence of embedding capacity of images to their content, we proposed an ensemble steganalyzer to estimate the embedding capacity of each cover image. Since the content of cover images has less significance in steganography, therefore to have more security, the steganographer... 

This paper presents a cover selection steganography method based on introduction of a technique for computing steganography capacity as a property of images. An ensemble system that uses different steganalyzer units, determines the upper bound of embedding rate in a cover image. In this technique, each steganalyzer unit is a combination of multiple steganalyzers with a same type but each one trained to detect stego images with a certain payload. Our proposed method minimizes the risk of detection by selecting a proper cover image that its steganography capacity is sufficient to hide a specific secret data securely. Experimental results demonstrate the efficiency and practicability of the... 

Steganography is the art of hiding information in a cover media without attracting attention. One of the cover media which can be used for steganography is speech. In this paper, we propose a new speech steganography in wavelet domain. In this method, lifting scheme is used to create perfect reconstruction Int2Int wavelets. The data is hidden in some of the Least Significant Bits (LSB) of detail wavelet coefficients. The LSB bits for hiding are selected with a new adaptive algorithm. This algorithm does not hide information in silent parts, so there is no need for silent detection algorithms. This method has zero error in hiding/unhiding process, while normal wavelet domain LSB has about 0.2... 

In recent years by growing computer applications, new technologies are also invented. Meanwhile new issues are faced such as security. One of the security areas is hidden exchange of information which contains methods such as cryptography and steganography. Steganography is the art of hiding data in a cover media such as image or sound. In this paper a new method for Steganography in Persian and Arabic texts is presented. In this method pseudo-space character is used for hiding the data. This character prevents the Persian and Arabic letters from joining but without adding a space between the two and keeps the words closer together. Its code is 200C in Unicode hex notation. This character... 

The hidden, real-time sending and display of information, esp. in public places, has since long received attention and faced many challenges. Therefore, different methods have been proposed so far for hiding information in different cover media. In this paper I propose a new method for the real-time hiding of information without need to any storage cover media. This method is based on the real-time hiding of information in output screens of the instrument (such as screens shown by the monitor). This method of steganography is very similar to the two discussions of image steganography and video steganography. The idea suggested in this paper was simulated on a PC computer by using the Pascal...