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In reversible data-hiding techniques, the quality of the steganographic image and its embedding capacity are the most crucial characteristics. The main objective of this study is to enhance the Biswapati et al. approach, which embeds secret data directly in interpolated pixels without taking context pixel properties into account. Additionally, they recorded an extremely large position value of the weighted matrix, which led to a significant amount of visual distortion. To deal with this issue, a novel reversible data-hiding method based on a multilayer center folding technique (MCFT) is developed. The suggested approach divides the interpolated cover image into 5 × 5 non-overlapping blocks and then sorts them in descending order of standard deviations. As a result of this sorting, edges and textures are more effectively preserved while also reducing the appearance of frequent interpolation defects. Unlike previous weighted matrix approaches, the position value of the weighted matrix is not embedded directly to generate the stego-image. MCFT is used before embedding to reduce the difference between an image pixel and a stego pixel so that image quality is not destroyed. The Huffman encoding technique is used to preprocess the acquired secret data to increase the embedding capacity as much as feasible. Additionally, to increase embedding rates, dual images are used for exploiting the characteristics of exploiting modification direction. The findings achieved significantly outperform state-of-the-art algorithms, which provide visual quality of more than 50.8 dB peak signal-to-noise ratio PSNR. When compared to modern techniques, the approach also offers the highest level of security and can retrieve the original image without losing any data. [ABSTRACT FROM AUTHOR]

Cloud computing is a technology that holds great promise and has potential to revolutionize the healthcare sector. Many security and privacy issues are brought up by the cloud's centralization of data for both patients and healthcare professionals. There is a need for maintaining secrecy in communication in exchanging medical data between the sender and the receiver, which can be done by cryptography. This article presents a cryptographic algorithm (encryption and decryption) to have a secure communication of digital health care confidential data using DNA cryptography and Huffman coding. The interesting property is the cipher size obtained from our algorithm is equal to the size of the cipher obtained from the character set of given data. Security analysis is provided to show the security of data when stored and transmitted to the cloud. The cryptographic requirements, key space analysis, key and plain text sensitivity, sensitive score analysis, sensitivity and specificity, optimal threshold, randomness analysis, uniqueness of implementation, entropies of binary bits, DNA bases, DNA bases with Huffman code, Huffman encoded binary bits and cloud service provider's risk are analyzed. The method proposed is compared with other cryptographic methods and results that it is more secure and stronger than other methods. [ABSTRACT FROM AUTHOR]

In the recent couple of years, due to the accelerated popularity of the internet, various organizations such as government offices, military, private companies, etc. use different transferring methods for exchanging their information. The Internet has various benefits and some demerits, but the primary bad mark is security of information transmission over an unreliable network, and widely uses of images. So, Steganography is the state of the art of implanting a message in the cover objects, that nobody can suspect or identify it. Therefore, in the field of cover steganography, it is very critical to track down a mechanism for concealing data by utilizing different blends of compression strategies. Amplifying the payload limit, and robustness, and working on the visual quality are the vital factors of this research to make a reliable mechanism. Different cover steganography research strategies have been recommended, and each adores its benefits and impediments but there is a need to foster some better cover steganography implements to accomplish dependability between the essential model of cover steganography. To handle these issues, in this paper we proposed a method in view of Huffman code, Least Significant Bits (LSB) based cover steganography utilizing Multi-Level Encryption (MLE) and colorless part (HC-LSBIS-MLE-AC) of the picture. It also used different substitution and flicking concepts, MLE, Magic matrix, and achromatic concepts for proving the proficiency, and significance of the method. The algorithm was also statistically investigated based on some Statistical Assessment Metrics (SAM) such as Mean Square Error (MSE), Peak Signal Noise Ratio (PSNR), Normalized Cross Correlation (NCC), Structural Similarity Index Metric (SSIM), etc. and different perspectives. The observational outcomes show the likelihood of the proposed algorithm and the capacity to give unwavering quality between security, payload, perception, computation, and temper protection. [ABSTRACT FROM AUTHOR]

Many confidential multimedia, such as personal privacy, commercial, and military secrets, are transmitted on the Internet. To prevent this confidential multimedia from being eavesdropped on by illegal users, information-hiding technology is a leading research topic nowadays. One of the important research topics of information-hiding technology is coverless information hiding, which utilizes the unchanged property of its multimedia carrier to hide secret information. In this paper, we propose two schemes that employ the average pixel value of an image. The first is an extension of the Coverless Information Hiding Based on the Most Significant Bit (CIHMSB) scheme, referred to as E-CIHMSB. In the E-CIHMSB, we build an extended matrix containing the image fragment's average pixel value. The second scheme is a combination theory-based CIHMSB, referred to as CB-CIHMSB. In the CB-CIHMSB, we construct the combined matrix. E-CIHMSB and CB-CIHMSB embed the secret bits by changing the most significant bits of the chosen pixel in the matrix. Experimental results show that our schemes achieved higher hiding capacity than previous related schemes. Moreover, the proposed scheme is more robust against steganalysis tools and image quality attacks such as Additive Gaussian White Noise (AWGN), Salt & Pepper noise, low-pass filtering attacks, and JPEG compression attacks than CIHMSB. [ABSTRACT FROM AUTHOR]

Steganography is the practice of hiding data, such as images, videos, or text, within a cover image without it being detectable by the human eye. Several factors, such as the capacity, security, and robustness of the technique, are essential when transferring information using this method. In this study, we propose a new approach to image steganography that improves the Least Significant Bit (LSB) technique by utilizing images of 24 bits in each pixel. Improving the capacity and security of LSB-based steganography requires a combination of techniques, such as indirect embedding, embedding in multiple channels, and applying cryptographic and compression techniques. This approach conducts by encrypting each compressed secret message bit with the most significant bit of the red channel and then saving the output bit (hidden bit) in the least significant bit of the (green/blue) channel according to the row value (odd/ even). To further security, the suggested approach uses multi-level encryption; employs RSA to encrypt the secret message before applying the Huffman compression and encrypting the hidden bit by (XOR/XNOR) in the embedding method based on the row value of the pixel. Meanwhile, it is planned to use the Huffman coding technique to shorten the length of the encrypted message that will be inserted in the cover image. For the color photos in this work, the standard images were acquired from a standard dataset (USC-SIPI). The suggested approach performs better when measured in terms of mean square error (MSE), peak signalto- noise ratio (PSNR), and comparison to findings from related prior efforts. [ABSTRACT FROM AUTHOR]

JPEG steganography has become a research hotspot in the field of information hiding. However, the capacity of conventional JPEG steganography methods is hard to meet the requirements in high-capacity application scenarios and also can not extract secret messages accurately after JPEG compression. To mitigate these problems, we propose a high-capacity and robust JPEG steganography based on adversarial training called HRJS, which implements an end-to-end framework in the JPEG domain for the first time. The encoder is responsible for embedding the secret message while the decoder can reconstruct the original secret message. To enhance robustness, an attack module forces the neural network to automatically learn how to correctly recover the secret message after an attack. Experimental results show that our method achieves near 100 % decoding accuracy against JPEG_50 compression at 1/3 bits per channel (bpc) payload while preserving the imperceptibility of the stego image. Compared with conventional JPEG steganography methods, the proposed method is feasible with high capacity (e.g., 1 bpc) and has an obvious advantage in terms of robustness against JPEG compression at the same time. [ABSTRACT FROM AUTHOR]

With the effect of digitalization, the transfer of all text documents over the Internet rather than human transmission has increased, and this situation has revealed the idea that text documents can be used as a carrier that can safely store information. Realizing that methods such as word-line shifting, usage of spaces, replacement of the word with its synonym are fragile against steganalysis, led to new searches and it was determined that deep learning models were more resistant to detecting the presence of hidden words. In this study, the text generation based on the information that is wanted to be hidden without a carrier text, both at word and character level, was performed. Arithmetic coding, perfect tree and Huffman coding methods were used as secret information embedding methods in text generation based on word level. In this part of the study, bidirectional LSTM architecture with attention mechanism was created as language model. In text generation based on character level, a new secret information embedding algorithm is created by combining the LZW compression algorithm with the Char Index (LZW-Char Index Encoding) method. The character-level model is created as a result of using the encoder–decoder architecture together with bidirectional LSTM and Bahdanau attention. The proposed method was evaluated from the perspectives of information embedding efficiency, information imperceptibility and hidden information capacity. As a result of the experiments, it was determined that the method exceeded the state-of-the-art performance and was more resistant to steganalysis. [ABSTRACT FROM AUTHOR]

Today, the transmission of hypersensitive data through public communication, poses a real problem for an unauthorized recipient which makes information security very important. The basic idea behind the proposed research work is to exploit the robustness of the genetic material in order to improve and outperform the performance of other conventional algorithm. In this paper, Huffman coding method has been adopted to develop a new and efficient symmetric DNA encryption algorithm. Firstly, the algorithm codifies the secondary DNA key which is extracted from the main DNA key according to Huffman coding. Then an XOR is applied between the coded DNA sequence and the plain-image. And in order to strengthen our algorithm, we have performed diffusion with a permutation box. [ABSTRACT FROM AUTHOR]

Building a balanced relation between image quality and the payload, the robustness of the method in facing electronic attacks and securing data, all the mentioned processes represent the main challenge in steganography. Here, a novel approach to steganography is suggested using Vigenere Cipher and Huffman Coding methods to encrypt and compress the mystery message content. This approach will raise the security and ensure the message content cannot be extracted without earlier knowledge of decrypting rules and the Huffman Dictionary Table. Later, the image is segmented into blocks, size (w * h) groups for each block and with each group having n pixels. Subsequently, the knight tour algorithm and arbitrary function are utilized to select which blocks and groups can be used to conceal the mystery digit within a specific pixel in the group randomly. This is to address the weakness of the Exploiting Modification Direction (EMD) technique that uses a serial selection to enhance the robustness of the suggested scheme. The EMD technique is then utilized to insert the mystery digits inside a specific pixel. Later, the chi-square method is employed to apply statistical attacks on the stego-image to estimate the suggested scheme robustness. The empirical outcomes show that the suggested scheme is more efficient compared to the old Steganography schemes with respect to Imperceptibility by PSNR of 55.71 dB, the Payload of 52,400 bytes and the robustness. [ABSTRACT FROM AUTHOR]

Image steganalysis has been widely studied, most of which can only complete the binary task of identifying the existence of hidden bits in an inquiry image. Currently, although some algorithms have been proposed to locate hidden bits, most of them mainly focus on the spatial domain, while usually ignoring the study of locating secret bits hidden in DCT domain for JPEG image. To address that challengeable problem, in this paper, towards two classical steganographic algorithms JSteg and F5, hiding bits in DCT domain, we propose a novel payload location method. The principal step of payload location is to estimate the cover image. We novelly propose to assign the different weights to the DCT coefficient residual in virtue of the texture of regions measured by the local variance, leading to the remarkable improvement of location results. Compared with the state of the art, the numerical experiments empirically verify that our proposed location method achieves the superior performance. In particular, when locating hidden bits in JSteg steganographic images with quality factor of 95 at the payload 0.1, the accuracy of location is remarkably improved from 46.18% to 90.22%. [ABSTRACT FROM AUTHOR]

Information security is one of the main aspects of processes and methodologies in the technical age of information and communication. The security of information should be a key priority in the secret exchange of information between two parties. In order to ensure the security of information, there are some strategies that are used, and they include steganography and cryptography. An effective digital image-steganographic method based on odd/even pixel allocation and random function to increase the security and imperceptibility has been improved. This lately developed outline has been verified for increasing the security and imperceptibility to determine the existent problems. Huffman coding has been used to modify secret data prior embedding stage; this modified equivalent secret data that prevent the secret data from attackers to increase the secret data capacities. The main objective of our scheme is to boost the peak-signal-to-noise-ratio (PSNR) of the stego cover and stop against any attack. The size of the secret data also increases. The results confirm good PSNR values in addition of these findings confirmed the proposed method eligibility. [ABSTRACT FROM AUTHOR]

Steganography is one of the cryptography techniques where secret information can be hidden through multimedia files such as images and videos. Steganography can offer a way of exchanging secret and encrypted information in an untypical mechanism where communicating parties can only interpret the secret message. The literature has shown a great interest in the least significant bit (LSB) technique which aims at embedding the secret message bits into the most insignificant bits of the image pixels. Although LSB showed a stable performance of image steganography yet, many works should be done on the message part. This paper aims to propose a combination of LSB and Deflate compression algorithm for image steganography. The proposed Deflate algorithm utilized both LZ77 and Huffman coding. After compressing the message text, LSB has been applied to embed the text within the cover image. Using benchmark images, the proposed method demonstrated an outperformance over the state of the art. This can proof the efficacy of using Deflate as a data compression prior to the LSB embedding. [ABSTRACT FROM AUTHOR]

Due to a large number of user-uploaded images, social networks have become secure channels for covert communication. However, the JPEG recompression of social networks changes the DCT coefficients of stego images, resulting in the failure of adaptive steganography. To achieve steganography in lossy channels, robust steganography has been proposed. In this letter, the ability against JPEG recompression of robust steganography is further improved by introducing a robustness cost function. For calculating the robustness cost, a robustness model based on the spatial domain calculated from DCT coefficients is firstly proposed. Then the robustness cost is acquired by measuring the distance between the spatial pixels calculated from modified DCT coefficients and the robustness model adjusted spatial pixels. Combining the distortion function and the robustness cost function, the method proposed has considerable robustness performance while maintaining satisfying security performance. Experimental results show that with the maximum reduction of 4.04% on security performance, the algorithm proposed has a significant improvement on robustness performance compared with state-of-the-art robust steganography. [ABSTRACT FROM AUTHOR]

Digital image steganography is now one of the effective methods for exchanging confidential information over the public network. One of the major challenges is to protect secret data embedded in to image against JPEG compression. This paper introduces a new method for image steganography which immune to JPEG compression with 100% retrieval rate of secret information up to 8192 bits payload with maintaining good Imperceptibility. The proposed algorithm is developed using DC coefficients of Discrete Cosine Transform (DCT) technique that resistant against lossy JPEG compression attack. The proposed algorithm can belong to the image realization steganography in which instead of actually embedding secret information directly to the cover image, key is derived with the combination of secret message and cover image and then the key is embed in the MSBs of the DC values in the selected blocks of DCT. The simulation test environment is used to perform a number of experiments on a standard dataset and to compare results with existing research. Standard parameters such as PSNR, Payload, BPP, SSIM and NCC are considered to evaluate the performance of the proposed algorithm. Efficiency of proposed work has been corroborated by conducting different experiments on various types of other attacks as well. Our proposed algorithm is surviving under JPEG compression attack for any quality factor range from 10 to 90. [ABSTRACT FROM AUTHOR]

In every system of security, to keep important data confidential, we need a high degree of protection. Steganography can be defined as a way of sending confidential texts through a secure medium of communications as well as protecting the information during the process of transmission. Steganography is a technology that is used to protect users' security and privacy. Communication is majorly achieved using a network through SMS, e-mail, and so on. The presented work suggested a technology of text hiding for protecting secret texts with Unicode characters. The similarities of glyphs provided invisibility and increased the hiding capacity. In conclusion, the proposed method succeeded in securing confidential data and achieving high payload capacity by using the Huffman compression algorithm, which was implemented on an unlimited text length. In addition, this approach has the ability to hide a single bit in every digit or letter in the cover file. Also, the approach meets the cognitive transparency and does not make the modifications apparent on the original data. The method suggested in this work increases the security level through coding a secret message before embedding it within the cover text, with the use of the Advanced Encryption Standard (AES) algorithm. [ABSTRACT FROM AUTHOR]

To further explore the characteristics of the steganographic noise signal in the adaptive JPEG steganographic images, this paper proposed a noise-aware residual network for JPEG image steganalysis. The proposed network included three components, noise-aware component, noise analysis component and judgement component. First, noise-aware component extracted the noise of an image, it used denoising network to offer more comprehensive information related to steganography. Then, noise analysis component got discriminative features from image noise related information. Last,judgement network gave the final detection result. Moreover, residual connections integrated high-level features and low-level features and prevented gradient vanishing and exploding. Experiments under various conditions show that the network has an advanced performance, and has better generalization ability. [ABSTRACT FROM AUTHOR]

Social networks are everywhere and currently transmitting very large messages. As a result, transmitting secret messages in such an environment is worth researching. However, the images used in transmitting messages are usually compressed with a JPEG compression channel, which is lossy and damages the transmitted data. Therefore, to prevent secret messages from being damaged, a robust JPEG steganography is urgently needed. In this paper, a secure robust JPEG steganographic scheme based on an autoencoder with an adaptive BCH encoding (Bose-Chaudhuri-Hocquenghem encoding) is proposed. In particular, the autoencoder is first pretrained to fit the transformation relationship between the JPEG image before and after compression by the compression channel. In addition, the BCH encoding is adaptively utilized according to the content of cover image to decrease the error rate of secret message extraction. The DCT (Discrete Cosine Transformation) coefficient adjustment based on practical JPEG channel characteristics further improves the robustness and statistical security. Comparisons with prior state-of-the-art schemes demonstrate that the proposed robust JPEG steganographic algorithm can provide a more robust performance and statistical security. [ABSTRACT FROM AUTHOR]

The Vernam-Cipher is known as a one-time pad of algorithm that is an unbreakable algorithm because it uses a typically random key equal to the length of data to be coded, and a component of the text is encrypted with an element of the encryption key. In this paper, we propose a novel technique to overcome the obstacles that hinder the use of the Vernam algorithm. First, the Vernam and advance encryption standard AES algorithms are used to encrypt the data as well as to hide the encryption key; Second, a password is placed on the file because of the use of the AES algorithm; thus, the protection record becomes very high. The Huffman algorithm is then used for data compression to reduce the size of the output file. A set of files are encrypted and decrypted using our methodology. The experiments demonstrate the flexibility of our method, and it is successful without losing any information. [ABSTRACT FROM AUTHOR]

This paper proposes a new framework of lossless data hiding (LDH) in JPEG images. The proposed framework contains two algorithms, i.e., the optimized basic LDH and the relay transfer based extension. In the basic algorithm, we aim to preserve the filesize after data embedding. The data hiding process is optimized by variable-length-code (VLC) mapping, combination and permutation. In the extended algorithm, we focus on embedding more bits into the bitstream with a condition that the filesize increment is allowed. To decrease the filesize increment, we propose a relay transfer based algorithm to preprocess the JPEG bitstream. Subsequently, we embed data into the processed bitstream using the basic LDH. Both algorithms provide better performances than previous arts. After lossless data hiding, the marked JPEG bitstream is compliant to common JPEG decoders. Since all operations are implemented on VLCs and the Huffman codes, no distortion is generated on the image pixels. Experimental results demonstrate that the proposed approach outperforms previous methods. [ABSTRACT FROM AUTHOR]

One must compress data prior to sending it to the internet since it helps minimize time and the cost. The main aim of the essay is to develop and design a systemic and a secure method for encrypting data, so as it can be used in executing a lossless compacting steganography method. The technique can be used to decrease the amount of every transmitted data aiding fast transmission while using slow internet or take a small space ion a disk. The paper proposes a compacting with stenography method which might be used to hide of data with significant security and also a perfect invisibility while using a combination of RSA (Rivest–Shamir–Adleman) cryptography method and also used steganography proficiency which are Huffman coding, Run-length encoding (RLE), or Discrete Wavelet Transform (DWT) with Least Significant Bits (LSB) steganography technique. The first step is grounded on the RSA skill to both decrypts and encrypt confidential messages. The next step is compression, which is Huffman coding based techniques that will be used to compress the sensitive data through lossless technology, RLE, which is a more natural way to compress data or DWT based that compacts cover image through lossy compression in order reducing the cover image's dimensions. LSB will then be used to implant the encrypted pieces of information in the compacted cover image. This system shows high ranking performance and a systematic system as compared to other states [1-5] of the structure that uses simulation outcomes. [ABSTRACT FROM AUTHOR]

In this paper, we propose an efficient steganography method in the compressed codes of absolute moment block truncation coding (AMBTC). Many recent related schemes focus on implementing reversible data hiding in compressed AMBTC bit stream. However, the reconstructed image of AMBTC is already lossy and the strict reversibility severely limits embedding capacity. Due to the simplicity and regularity of AMBTC codes, implementing irreversible hiding scheme causes very slight loss visual distortion of reconstructed image in exchange of significant improve in embedding capacity. In proposed scheme, smoothness of AMBTC compressed trio is firstly detected, which is then indicated by substituting the LSB of high quantity level with flag bit. For smooth trios, the differences between both quantity levels are firstly encoded by Huffman coding and then concatenated with secret data to generate modified low quantity levels. Meanwhile, all bits in bit planes of smooth trios are substituted with secret data as well. For complex trio, secret bits are only embedded into quantity levels, which is similar to smooth trio except for the differences are encoded by Lloyd-Max quantization. Experimental results indicate that proposed scheme outperforms prior methods both in imperceptivity and embedding capacity, which confirms the effectiveness and superiority of our work. [ABSTRACT FROM AUTHOR]

Due to their use in daily life situation, demand for remote health applications and e-health monitoring equipment is growing quickly. In this phase, for fast diagnosis and therapy, information can be transferred from the patient to the distant clinic. Nowadays, the most chronic disease is cardiovascular diseases (CVDs). However, the storage and transmission of the ECG signal, consumes more energy, bandwidth and data security which is faced many challenges. Hence, in this work, we present a combined approach for ECG data compression and cryptography. The compression is performed using adaptive Huffman encoding and encrypting is done using AES (CBC) scheme with a 256-bit key. To increase the security, we include Diffie- Hellman Key exchange to authenticate the receiver, RSA key generation for encrypting and decrypting the data. Experimental results show that the proposed approach achieves better performance in terms of compression and encryption on MIT-BIH ECG dataset. [ABSTRACT FROM AUTHOR]

Steganography is a hidden way of communication, where one person communicates with the other by using some medium under the garb of a cover, without any suspicion created on the part of any unauthorized intermediary about the existence of the secret message. Linguistic steganography is about hiding information in natural language text. Synonym substitution is an important transformation used in linguistic steganography. In this paper, we are going to show a method of redesigning the change tracking technique for hiding the secret message in Microsoft Word document to increase the embedding capacity and to decrease the suspicion of any intermediary about the message's existence. The secret message in bit form is concealed by performing linguistic steganography using synonym substitution method. In conventional change tracking technique for information hiding in Microsoft Word document, the generated Huffman's codes of rare words are lengthier as compared to common words, leading to more suspicion in the stego-document due to the usage of rare words as compared to common words as synonyms. To overcome this problem, the proposed algorithm is designed in such a way that familiar synonyms are used more often to hide more bits and avoid suspicions. [ABSTRACT FROM AUTHOR]

Information security is very important and has been widely implemented. Cryptography and steganography are two common methods that can be implemented to secure and conceal the information. In this research, the proposed AES algorithm for cryptography and DWT for steganography. However, in case of implementing DWT as steganography, there is a weakness which is a lower capacity. Based on DWT's problem, proposed Huffman Coding to reduce the total of the message's bit and increase the capacity. In the implementation, a message will be processed by using AES and compressed by using Huffman Coding then conceal in a cover using DWT. After doing several experiments using a 128x128 pixel message image and a 512x512 pixel of the cover image, achieved the average of MSE is 1.5676 and the average of PSNR result is above 40 db which is 46.1878. [ABSTRACT FROM AUTHOR]

In earlier reported chat-based steganography techniques, only direct communication between the sender and receiver was considered which can raise suspicion for further investigations by an attacker. If the adversary traces the communication between the two, he may investigate to find out the data shared during communication, can alter the content, or destroy it. In such a situation, a steganography system is required which can bypass adverse attention through indirect communication instead of direct communication. In this paper, we propose a new framework to camouflage hidden communication between the transceivers. The framework is based on online social networking and video-sharing website's communication. The secret message is communicated using comment features of these social networking and video-sharing websites in a totally new way compared with earlier approaches. Stego-comment is generated by performing synonym-substitution based on Huffman code on the auto-summarized previous comments of a chosen post. The stego-comment does not raise any suspicion to the intermediary by being technically similar to other comments which may not have any hidden message, which makes this method successful. Similarity indices of the stego-comment with respect to other comments are calculated using a String Similarity Tool which uses fuzzy comparison functions between strings for one sample dataset. The proposed method gives average bit-rate (as a measure of embedding efficiency) of 9.04 bits per sentence for a set of five different case studies which is high compared with average bit rates found in the literature. This communication cannot be traced between the communicators through traffic analysis in any easy way due to the absence of any direct communication. [ABSTRACT FROM AUTHOR]

To remove the ragged edges of the text, some of the text editors increase the size of some between words spaces. This process is named as "Justify". Different editors use different algorithms for justifying the texts. In this paper we introduce a hiding method which is based on justified text in a pdf file. In this proposed method, first we compress the secret message by Huffman coding. Then we choose some special lines of the cover as host lines. The embedding operation occurs by the replacement of the added spaces by the normal spaces of the host lines. Finally we re-pdf the file and send it. This scheme has a key, and in each use we can choose a new key for increasing the security of the communications. In this proposed method we can embed more information in a cover-text compared with several other text steganography schemes. Also the size of the file of the cover is not changed in this method. The next advantage of this method is that the parties of secret communication do not need to send electronic files and furthermore this method is printable. [ABSTRACT FROM AUTHOR]

A central question in the classical information theory is that of source compression, which is the task where Alice receives a sample from a known probability distribution and needs to transmit it to the receiver Bob with small error. This problem has a one-shot solution due to Huffman, in which the messages are of variable length and the expected length of the messages matches the asymptotic and independent identically distributed (i.i.d.) compression rate of the Shannon entropy of the source. In this paper, we consider a quantum extension of above task, where Alice receives a sample from a known probability distribution and needs to transmit a part of a pure quantum state (that is associated with the sample) to Bob. We allow entanglement assistance in the protocol, so that the communication is possible through classical messages, for example using quantum teleportation. The classical messages can have a variable length, and the goal is to minimize their expected length. We provide a characterization of the expected communication cost of this task, by giving a lower bound that is near optimal up to some additive factors. A special case of above task, and the quantum analogue of the source compression problem, is when Alice needs to transmit the whole of her pure quantum state. Here, we show that there is no one-shot interactive scheme which matches the asymptotic and i.i.d. compression rate of the von Neumann entropy of the average quantum state. This is a relatively rare case in the quantum information theory where the cost of a quantum task is significantly different from its classical analogue. Furthermore, we also exhibit similar results for the fully quantum task of quantum state redistribution, employing some different techniques. We show implications for the one-shot version of the problem of quantum channel simulation. [ABSTRACT FROM AUTHOR]

In this paper, a novel linguistic steganography with high imperceptibility and undetectability is proposed via secret message compression and candidate text selection. The length of the practical embedded payload can be reduced by the proposed word indexing compression algorithm(WIC), while a best stego text with high undetectability can be selected from candidates by the stego text selection strategy. WIC algorithm losslessly compresses the secret message by combining a minimum maximum weight algorithm with Huffman coding under the help of the candidate cover text. To improve the anti-steganalysis capability, ten cover texts with small compression ratios are selected from a huge cover text set, and are embedded the corresponding compressed secret message by using synonym substitutions. Only one stego text is selected by a given rule derived from the distance between a cover text and its stego text. Experimental results show that the proposed compression algorithm achieves better compression ratios than Huffman and LZW coding algorithms leading to higher embedding efficiency, and our steganography performs well in anti-steganalysis capability with compression and the stego text selection rule. [ABSTRACT FROM AUTHOR]

The efficiency of any cryptographic algorithms depends on both security and operational speed. When a message is encrypted using any cryptosystems it produces only one level of security because it converts the plaintext into ciphertext where the ciphertext is not easily tractable. To increase the security in any cryptographic algorithm, normally the size of the plaintext and key should be taken very largely. Further, additional levels of security have been introduced in this paper to enhance the security. For that, the message to be encrypted is encoded first so that original form of the message is altered called the first level of security. The encoded message is sometimes too large so that it is compressed which results in changing the encoded form of message called second level security. Finally, the compressed message is encrypted using any one of the public-key cryptosystems by determining the block size dynamically which produces the third level of security. Thus, an integrated approach is proposed called encoded compressed cryptosystem in this paper. [ABSTRACT FROM AUTHOR]

It is general fact that even after enormous expansion of wireless communication there are still dead regions that hampers the effective communication. With exponential rise in the smart phones, a new layer of communication has evolved that could address the concerns of dead regions and capacity barriers. D2D is the evolving communication technology which focuses on short distance hops between the public devices to reach the destination. The major drawback of this technology is that most of the devices are public hence trustworthiness of the entire channel needs to be addressed in order to make it a viable solution. In this paper, we introduce a novel hybrid cryptographic approach that could address multiple eavesdroppers' scenario. This approach incorporates both Huffman coding and Binary coding to enhance the crypto benefits for the information transmitted over D2D channel that consists of several public devices. The dual-crypto nature of the proposed algorithm offers higher efficiency, better security and improved key transmission. Thus, the proposed hybrid cryptographic approach is robust in nature while easy and simple to operate. In addition, the proposed approach could recover the original information without any distortion from the encrypted data making the approach lossless in nature. Further simulation results prove that the proposed offers confidentiality to the transmitted to data while addressing the network capacity crunch. [ABSTRACT FROM AUTHOR]

• This is the first work that introduces adversarial mechanism into robust steganography to improve the security of steganography. Adversarial dither modulation algorithm is proposed to guide the dither directions via the signs and magnitudes of cover gradients calculated from pre-trained steganalyzer. • According to "Matching Robust" or "Upward Robust" scene, we select proper embedding elements to balance the robustness against JPEG compression and steganography security. • Extensive experiments show that the proposed adversarial robust steganography could significantly improve the steganography security and maintain strong robustness. Traditional image steganography assumes that the transmission channel is lossless, thus it can not assure the correct extraction of hidden secret messages in real social networks. Recently, some robust image steganographic methods have been proposed to resist lossy JPEG compression. In this paper, we first introduce adversarial mechanism into robust image steganography to enhance steganography security. Instead of modifying embedding costs in traditional adversarial embedding steganography, we propose adversarial dither modulation algorithm according to the cover gradients calculated from a pre-trained CNN (Convolutional Neural Networks)-based steganalyzer. This algorithm determines the dither directions via the signs and magnitudes of the cover gradients. In addition, we carefully select proper embedding elements according to the prior information of the transmission channel to obtain a good tradeoff between "robustness" and "security" for robust steganography. Experimental results show that the proposed method can achieve significant improvements on security while preserving very good robustness compared with related work. [ABSTRACT FROM AUTHOR]

In this study, capacity and security issues of text steganography have been considered by proposing a compression based approach. Because of using textual data in steganography, firstly, the employed data compression algorithm has to be lossless. Accordingly, Huffmann coding has been chosen due to its frequent use in the literature and significant compression ratio. Besides, the proposed method constructs and uses stego-keys in order to increase security. Secret information has been hidden in the chosen text from the previously constructed text base that consists of naturally generated texts. Email has been chosen as communication channel between the two parties, so the stego cover has been arranged as a forward mail platform. As the result of performed experiments, average capacity has been computed as 7.962 % for the secret message with 300 characters (or 300∙8 bits). Finally, comparison of the proposed method with the other contemporary methods in the literature has been carried out in Section 5. [ABSTRACT FROM AUTHOR]

Digital rights management (DRM) system is a promising technique to allow copyrighted content to be commercialized in digital format without the risk of revenue loss due to piracy. However, traditional DRMs are achieved with individual function modules of cryptography and watermarking. Therefore, all digital contents are temporarily disclosed in perfect condition via decryption process in the user-side risking illegal redistribution. This paper describes the basic idea of a novel DRM method composed of an incomplete cryptography using invariant Huffman code length feature and the user identification mechanism to control the quality of digital contents. The proposed incomplete cryptography consists of two processes: the incomplete encoding and the incomplete decoding. These processes are presented by randomly selecting the coefficients that belong to the same category or different category of Huffman code. In our scheme, the copyright information is embedded into the decoded content during the decoding process, and the size of digital contents are invariant during the process. Experimental results with simulation confirmed that the modified codes are compatible with standard JPEG format, and revealed the proposed method to be suitable for DRM in the network distribution system. [ABSTRACT FROM AUTHOR]

We propose an optical security method for object authentication using photon-counting encryption implemented with phase encoded QR codes. By combining the full phase double-random-phase encryption with photon-counting imaging method and applying an iterative Huffman coding technique, we are able to encrypt and compress an image containing primary information about the object. This data can then be stored inside of an optically phase encoded QR code for robust read out, decryption, and authentication. The optically encoded QR code is verified by examining the speckle signature of the optical masks using statistical analysis. Optical experimental results are presented to demonstrate the performance of the system. In addition, experiments with a commercial Smartphone to read the optically encoded QR code are presented. To the best of our knowledge, this is the first report on integrating photon-counting security with optically phase encoded QR codes. [ABSTRACT FROM PUBLISHER]

In this paper we present a reversible image steganography technique based on Slantlet transform (SLT) and using advanced encryption standard (AES) method. The proposed method first encodes the message using two source codes, viz., Huffman codes and a self-synchronizing variable length code known as, T-code. Next, the encoded binary string is encrypted using an improved AES method. The encrypted data so obtained is embedded in the middle and high frequency sub-bands, obtained by applying 2-level of SLT to the cover-image, using thresholding method. The proposed algorithm is compared with the existing techniques based on wavelet transform. The Experimental results show that the proposed algorithm can extract hidden message and recover the original cover image with low distortion. The proposed algorithm offers acceptable imperceptibility, security (two-layer security) and provides robustness against Gaussian and Salt-n-Pepper noise attack. [ABSTRACT FROM AUTHOR]

• A novel design paradigm of distortion cost function for efficient JPEG steganography is proposed, which incorporates the statistics of both the spatial and DCT domains by a generalized Distortion Cost Domain Transformation (DCDT) function. • The proposed JPEG steganographic distortion cost function is represented in a more general exponential model, aiming to flexibly allocate the embedding data. • The proposed scheme can be easily extended to the mutually dependent embedding with the help of the proposed DCDT function. • Experimental results show that the proposed scheme can outperform other SOTA JPEG steganographic schemes, e.g., UERD, J-UNIWARD and GUED, and rival the BET with an order of magnitude lower computational complexity. • The proposed scheme can not only improve the performance against JPEG phase-aware steganalysis, but also broaden the applications of existing image steganographic schemes in spatial domain. Recently, with the introduction of JPEG (Joint Photographic Experts Group) phase-aware steganalysis features, e.g., GFR, the design of JPEG steganographic distortion cost function turns to maintain not only the statistical undetectability in DCT (Discrete Cosine Transform) domain but also in spatial domain. To tackle this issue, this paper presents a novel paradigm for the design of JPEG steganographic distortion cost function, which calculates the distortion cost via a generalized Distortion Cost Domain Transformation (DCDT) function. The proposed function comprises the decompressed pixel block embedding changes and their corresponding embedding distortion costs for unit change, where the pixel embedding distortion costs are represented in a more general exponential model, aiming to flexibly allocate the embedding data. In this way, the JPEG steganography could be formulated as the optimization problem of minimizing the overall distortion cost in its decompressed spatial domain, which is equivalent to maximizing its statistical undetectability against JPEG phase-aware steganalysis features. Experimental results show that the proposed DCDT equipped with HiLL (a spatial steganographic distortion cost function) is superior to other state-of-the-art JPEG steganographic schemes, e.g., UERD, J-UNIWARD, and GUED in resisting the detection of JPEG phase-aware feature-based steganalyzers GFR and SCA-GFR, and rivals BET-HiLL with one order of magnitude lower computational complexity, along with the possibility of being further improved by considering the mutually dependent embedding interactions. In addition, the proposed DCDT is also verified to be effective for different image databases and quality factors. [ABSTRACT FROM AUTHOR]

Encryption is one of the fundamental technologies that is used in digital rights management. Unlike ordinary computer applications, multimedia applications generate large amounts of data that has to be processed in real time. So, a number of encryption schemes for multimedia applications have been proposed in recent years. We analyze the following proposed methods for multimedia encryption: key-based multiple Huffman tables (MHT), arithmetic coding with key-based interval splitting (KSAC), and randomized arithmetic coding (RAC). Our analysis shows that MHT and KSAC are vulnerable to low complexity known- and/or chosen-plaintext attacks. Although we do not provide any attacks on RAC, we point out some disadvantages of RAC over the classical compress-then-encrypt approach. [ABSTRACT FROM PUBLISHER]

Two approaches for integrating encryption with multimedia compression systems are studied in this research, i.e., selective encryption and modified entropy coders with multiple statistical models. First, we examine the limitations of selective encryption using cryptanalysis, and provide examples that use selective encryption successfully. Two rules to determine whether selective encryption is suitable for a compression system are concluded. Next, we propose another approach that turns entropy coders into encryption ciphers using multiple statistical models. Two specific encryption schemes are obtained by applying this approach to the Huffman coder and the QM coder. It is shown that security is achieved without sacrificing the compression performance and the computational speed. This modified entropy coding methodology can be applied to most modern compressed audio/video such as MPEG audio, MPEG video, and JPEG/JPEG2000 images. [ABSTRACT FROM PUBLISHER]

Advanced Audio Coding (AAC) is currently the most widely used audio compression standard in Internet applications. In this paper, a large capacity secure steganography algorithm based on the compression parameters of AAC QMDCT is proposed. In order to improve the statistical security and the imperceptibility of steganography. Based on multi-view statistical distortion, which combines the statistical distribution of Huffman codewords, QMDCT's intra-frame and inter-frame statistical correlation, and the frequency perceptual masking in the psychoacoustic model, this paper presents a secure AAC steganography scheme SofMvD based on STCs. In the experimental results, the maximum embedding capacity of the proposed scheme is about 12 kbps. Compared with the existing methods, this method can improve steganalysis's ability to 8 % − 30 % and improve the auditory concealment of steganalysis without changing the embedding capacity. This scheme can also be extended to MP3. [Display omitted] • To improve the statistical security, the statistical characteristics of the Huffman codeword histogram distribution are proposed to design the distortion function of the steganography scheme, which can maintain the statistical distribution of Stego. • The correlations of the QMDCT coefficient of intra and inter frame are introduced into the steganography scheme's distortion function to improve the statistical security of the scheme. • To calculate the actual change in the audio signal of AAC, the actual masking threshold curve is used to measure the human hearing distortion, as one part of the steganography distortion function to improve the auditory imperceptibility of the Stego AAC. [ABSTRACT FROM AUTHOR]

Fuzzy extractors (Dodis et al., in Advances in cryptology—EUROCRYPT 2014, Springer, Berlin, 2014, pp 93–110) convert repeated noisy readings of a secret into the same uniformly distributed key. To eliminate noise, they require an initial enrollment phase that takes the first noisy reading of the secret and produces a nonsecret helper string to be used in subsequent readings. Reusable fuzzy extractors (Boyen, in Proceedings of the 11th ACM conference on computer and communications security, CCS, ACM, New York, 2004, pp 82–91) remain secure even when this initial enrollment phase is repeated multiple times with noisy versions of the same secret, producing multiple helper strings (for example, when a single person's biometric is enrolled with multiple unrelated organizations). We construct the first reusable fuzzy extractor that makes no assumptions about how multiple readings of the source are correlated. The extractor works for binary strings with Hamming noise; it achieves computational security under the existence of digital lockers (Canetti and Dakdouk, in Advances in cryptology—EUROCRYPT 2008, Springer, Berlin, 2008, pp 489–508). It is simple and tolerates near-linear error rates. Our reusable extractor is secure for source distributions of linear min-entropy rate. The construction is also secure for sources with much lower entropy rates—lower than those supported by prior (nonreusable) constructions—assuming that the distribution has some additional structure, namely, that random subsequences of the source have sufficient minentropy. Structure beyond entropy is necessary to support distributions with low entropy rates. We then explore further how different structural properties of a noisy source can be used to construct fuzzy extractors when the error rates are high, building a computationally secure and an information-theoretically secure construction for large-alphabet sources. [ABSTRACT FROM AUTHOR]