Biblio

Steganography is a data hiding technique, which is generally used to hide the data within a file to avoid detection. It is used in the police department, detective investigation, and medical fields as well as in many more fields. Various techniques have been proposed over the years for Image Steganography and also attackers or hackers have developed many decoding tools to break these techniques to retrieve data. In this paper, CAPTCHA codes are used to ensure that the receiver is the intended receiver and not any machine. Here a randomized CAPTCHA code is created to provide additional security to communicate with the authenticated user and used Image Steganography to achieve confidentiality. For achieving secret and reliable communication, encryption and decryption mechanism is performed; hence a machine cannot decode it using any predefined algorithm. Once a secure connection has been established with the intended receiver, the original message is transmitted using the LSB algorithm, which uses the RGB color spectrum to hide the image data ensuring additional encryption.

This paper describes our design and implementation of a covert channel over LoRa physical layer (PHY). LoRa adopts a unique modulation scheme (chirp spread spectrum (CSS)) to enable long range communication at low-power consumption. CSS uses the initial frequencies of LoRa chirps to differentiate LoRa symbols, while simply ignoring other RF parameters (e.g., amplitude and phase). Our study reveals that the LoRa physical layer leaves sufficient room to build a covert channel by embedding covert information with a modulation scheme orthogonal to CSS. To demonstrate the feasibility of building a covert channel, we implement CloakLoRa. CloakLoRa embeds covert information into a regular LoRa packet by modulating the amplitudes of LoRa chirps while keeping the frequency intact. As amplitude modulation is orthogonal to CSS, a regular LoRa node receives the LoRa packet as if no secret information is embedded into the packet. Such an embedding method is transparent to all security mechanisms at upper layers in current LoRaWAN. As such, an attacker can create an amplitude modulated covert channel over LoRa without being detected by current LoRaWAN security mechanism. We conduct comprehensive evaluations with COTS LoRa nodes and receive-only software defined radios and experiment results show that CloakLoRa can send covert information over 250m.

Some of the key challenges in steganography are imperceptibility and resistance to detection of steganalysis algorithms. Zero steganography is an approach to data hiding such that the cover image is not modified. This paper focuses on the generation of stego-key, which is an essential component of this steganographic approach. This approach utilizes DNA sequences and shifting and flipping operations in its binary code representation. Experimental results show that the key generation algorithm has a low cracking probability. The algorithm satisfies the avalanche criterion.

Most anti-collusion audio fingerprinting schemes are aiming at finding colluders from the illegal redistributed audio copies. However, the loss caused by the redistributed versions is inevitable. In this letter, a novel fingerprinting scheme is proposed to eliminate the motivation of collusion attack. The audio signal is transformed to the frequency domain by the Fourier transform, and the coefficients in frequency domain are reversed in different degrees according to the fingerprint sequence. Different from other fingerprinting schemes, the coefficients of the host media are excessively modified by the proposed method in order to reduce the quality of the colluded version significantly, but the imperceptibility is well preserved. Experiments show that the colluded audio cannot be reused because of the poor quality. In addition, the proposed method can also resist other common attacks. Various kinds of copyright risks and losses caused by the illegal redistribution are effectively avoided, which is significant for protecting the copyright of audio.

In our daily lives, the advances of new technology can be used to sustain the development of people across the globe. Particularly, e-government can be the dynamo of the development for the people. The development of technology and the rapid growth in the use of internet creates a big challenge in the administration in both the public and the private sector. E-government is a vital accomplishment, whereas the security is the main downside which occurs in each e-government process. E-government has to be secure as technology grows and the users have to follow the procedures to make their own transactions safe. This paper tackles the challenges and obstacles to enhance the security of information in e-government. Hence to achieve security data hiding techniques are found to be trustworthy. Reversible data hiding (RDH) is an emerging technique which helps in retaining the quality of the cover image. Hence it is preferred over the traditional data hiding techniques. Modification in the existing algorithm is performed for image encryption scheme and data hiding scheme in order to improve the results. To achieve this secret data is split into 20 parts and data concealing is performed on each part. The data hiding procedure includes embedding of data into least significant nibble of the cover image. The bits are further equally distributed in the cover image to obtain the key security parameters. Hence the obtained results validate that the proposed scheme is better than the existing schemes.

In recent years, image steganography is being considered as one of the methods to secure the confidentiality of sensitive and private data sent over networks. Conventional image steganography techniques use cover images to hide secret messages. These techniques are susceptible to steganalysis algorithms based on anomaly detection. This paper proposes a new approach to image steganography without using cover images. In addition, it utilizes Deoxyribonucleic Acid (DNA) sequences. DNA sequences are used to generate key and stego-image. Experimental results show that the use of DNA sequences in this technique offer very low cracking probability and the coverless approach contributes to its high embedding capacity.

Adaptive steganography aims to reduce distortion in the embedding process, typically using Syndrome Trellis Codes (STCs). However, in the case of non-adversarial noise, these are a bad choice: syndrome codes are fragile by design, amplifying the channel error rate into unacceptably-high payload error rates. In this paper we examine the fragility of STCs in the noisy channel, and consider how this can be mitigated if their use cannot be avoided altogether. We also propose an extension called Dual-Syndrome Trellis Codes, that combines error correction and embedding in the same Viterbi process, which slightly outperforms a straight-forward combination of standard forward error correction and STCs.

The transmission of medical image data in an open network environment is subject to privacy issues including patient privacy and data leakage. In the past, image encryption and information-hiding technology have been used to solve such security problems. But these methodologies, in general, suffered from difficulties in retrieving original images. We present in this paper an algorithm to protect key regions in medical images. First, coefficient of variation is used to locate the key regions, a.k.a. the lesion areas, of an image; other areas are then processed in blocks and analyzed for texture complexity. Next, our reversible data-hiding algorithm is used to embed the contents from the lesion areas into a high-texture area, and the Arnold transformation is performed to protect the original lesion information. In addition to this, we use the ciphertext of the basic information about the image and the decryption parameter to generate the Quick Response (QR) Code to replace the original key regions. Consequently, only authorized customers can obtain the encryption key to extract information from encrypted images. Experimental results show that our algorithm can not only restore the original image without information loss, but also safely transfer the medical image copyright and patient-sensitive information.

Searchable symmetric encryption (SSE) is an important technique for cloud computing. SSE allows encrypted critical data stored on an untrusted cloud server to be searched using keywords, returning correct data, but the keywords and data content are unknown by the server. However, an SSE database is not practical because the data is generally frequently modified even when stored on a remote server, since the server cannot update the encrypted data without decryption. Dynamic searchable symmetric encryption (DSSE) is designed to support this requirement. DSSE allows adding or deleting encrypted data on the server without decryption. Many DSSE systems have been proposed, based on link-list structures or blind storage (a new primitive). Each has advantages and drawbacks regarding function, extensibility, and efficiency. For a real system, the most important aspect is the tradeoff between performance and security. Therefore, we implemented several DSSE systems to compare their efficiency and security, and identify the various disadvantages with a view to developing an improved system.

Digital video has various types of entities, which are utilized as embedding domains to hide messages in steganography. However, nearly all video steganography uses only one type of embedding domain, resulting in limited embedding capacity and potential security risks. In this paper, we firstly propose to embed in multi-domains for video steganography by combining partition modes (PMs) and motion vectors (MVs). The multi-domain embedding (MDE) aims to spread the modifications to different embedding domains for achieving higher undetectability. The key issue of MDE is the interactions of entities across domains. To this end, we design two MDE strategies, which hide data in PM domain and MV domain by sequential embedding and simultaneous embedding respectively. These two strategies can be applied to existing steganography within a distortion-minimization framework. Experiments show that the MDE strategies achieve a significant improvement in security performance against targeted steganalysis and fusion based steganalysis.

In this research project, we are interested by finding solutions to the problem of image analysis and processing in the encrypted domain. For security reasons, more and more digital data are transferred or stored in the encrypted domain. However, during the transmission or the archiving of encrypted images, it is often necessary to analyze or process them, without knowing the original content or the secret key used during the encryption phase. We propose to work on this problem, by associating theoretical aspects with numerous applications. Our main contributions concern: data hiding in encrypted images, correction of noisy encrypted images, recompression of crypto-compressed images and secret image sharing.

There has been a growing expansion in the use of steganography, due to the evolution in using internet technology and multimedia technology. Hence, nowadays, the information is not secured sufficiently while transmitting it over the network. Therefore, information security has taken an important role to provide security against unauthorized individuals. This paper proposes steganography and cryptography technique to secure image based on hybrid edge detector. Cryptography technique is used to encrypt a secret image by using Vernam cipher algorithm. The robust of this algorithm is depending on pseudorandom key. Therefore, pseudo-random key is generated from a nonlinear feedback shift register (Geffe Generator). While in steganography, Hybrid Sobel and Kirch edge detector have been applied on the cover image to locate edge pixels. The least significant bit (LSB) steganography technique is used to embed secret image bits in the cover image in which 3 bits are embedded in edge pixel and 2 bits in smooth pixel. The proposed method can be used in multi field such as military, medical, communication, banking, Electronic governance, and so on. This method gives an average payload ratio of 1.96 with 41.5 PSNR on average. Besides, the maximum size of secret image that can be hidden in the cover image of size 512*512 is 262*261. Also, when hiding 64800 bits in baboon cover image of size 512*512, it gives PSNR of 50.42 and MSE of 0.59.

Now-a-days, video steganography has developed for a secured communication among various users. The two important factor of steganography method are embedding potency and embedding payload. Here, a Multiple Object Tracking (MOT) algorithmic programs used to detect motion object, also shows foreground mask. Discrete wavelet Transform (DWT) and Discrete Cosine Transform (DCT) are used for message embedding and extraction stage. In existing system Least significant bit method was proposed. This technique of hiding data may lose some data after some file transformation. The suggested Multiple object tracking algorithm increases embedding and extraction speed, also protects secret message against various attackers.

Steganography means hiding secrete message in cover object in a way that no suspicious from the attackers, the most popular steganography schemes is image steganography. A very common questions that asked in the field are: 1- what is the embedding scheme used?, 2- where is (location) the secrete messages are embedded?, and 3- how the sender will tell the receiver about the locations of the secrete message?. Here in this paper we are deal with and aimed to answer questions number 2 and 3. We used the popular scheme in image steganography which is least significant bits for embedding in edges positions in color images. After we separate the color images into its components Red, Green, and Blue, then we used one of the components as an index to find the edges, while other one or two components used for embedding purpose. Using this technique we will guarantee the same number and positions of edges before and after embedding scheme, therefore we are guaranteed extracting the secrete message as it's without any loss of secrete messages bits.

The barcode is an important link between real life and the virtual world nowadays. One of the most common barcodes is QR code, which its appearance, black and white modules, is not visually pleasing. The QR code is applied to product packaging and campaign promotion in the market. There are more and more stores using QR code for transaction payment. If the QR code is altered or illegally duplicated, it will endanger the information security of users. Therefore, the study uses infrared watermarking to embed the infrared QR code information into the explicit QR code to strengthen the anti-counterfeiting features. The explicit graphic QR code is produced by data hiding with error diffusion in this study. With the optical characteristics of K, one of the four printed ink colors CMYK (Cyan, Magenta, Yellow, Black), only K can be rendered in infrared. Hence, we use the infrared watermarking to embed the implicit QR code information into the explicit graphic QR code. General QR code reader may be used to interpret explicit graphic QR code information. As for implicit QR code, it needs the infrared detector to extract its implicit QR code information. If the QR code is illegally copied, it will not show the hidden second QR code under infrared detection. In this study, infrared watermark hidden in the graphic QR code can enhance not only the aesthetics of QR code, but also the anti-counterfeiting feature. It can also be applied to printing related fields, such as security documents, banknotes, etc. in the future.

With the rapid development of computer networks, multimedia information is widely used, and the security of digital media has drawn much attention. The revised photo as a forensic evidence will distort the truth of the case badly tampered pictures on the social network can have a negative impact on the parties as well. In order to ensure the authenticity and integrity of digital media, self-recovery of digital images based on information hiding is studied in this paper. Jarvis half-tone change is used to compress the digital image and obtain the backup data, and then spread the backup data to generate the reference data. Hash algorithm aims at generating hash data by calling reference data and original data. Reference data and hash data together as a digital watermark scattered embedded in the digital image of the low-effective bits. When the image is maliciously tampered with, the hash bit is used to detect and locate the tampered area, and the image self-recovery is performed by extracting the reference data hidden in the whole image. In this paper, a thorough rebuild quality assessment of self-healing images is performed and better performance than the traditional DCT(Discrete Cosine Transform)quantization truncation approach is achieved. Regardless of the quality of the tampered content, a reference authentication system designed according to the principles presented in this paper allows higher-quality reconstruction to recover the original image with good quality even when the large area of the image is tampered.

Organizations not only need to defend their IT systems against external cyber attackers, but also from malicious insiders, that is, agents who have infiltrated an organization or malicious members stealing information for their own profit. In particular, malicious insiders can leak a document by simply opening it and taking pictures of the document displayed on the computer screen with a digital camera. Using a digital camera allows a perpetrator to easily avoid a log trail that results from using traditional communication channels, such as sending the document via email. This makes it difficult to identify and prove the identity of the perpetrator. Even a policy prohibiting the use of any device containing a camera cannot eliminate this threat since tiny cameras can be hidden almost everywhere. To address this leakage vector, we propose a novel screen watermarking technique that embeds hidden information on computer screens displaying text documents. The watermark is imperceptible during regular use, but can be extracted from pictures of documents shown on the screen, which allows an organization to reconstruct the place and time of the data leak from recovered leaked pictures. Our approach takes advantage of the fact that the human eye is less sensitive to small luminance changes than digital cameras. We devise a symbol shape that is invisible to the human eye, but still robust to the image artifacts introduced when taking pictures. We complement this symbol shape with an error correction coding scheme that can handle very high bit error rates and retrieve watermarks from cropped and compressed pictures. We show in an experimental user study that our screen watermarks are not perceivable by humans and analyze the robustness of our watermarks against image modifications.

The security of image steganography is an important basis for evaluating steganography algorithms. Steganography has recently made great progress in the long-term confrontation with steganalysis. To improve the security of image steganography, steganography must have the ability to resist detection by steganalysis algorithms. Traditional embedding-based steganography embeds the secret information into the content of an image, which unavoidably leaves a trace of the modification that can be detected by increasingly advanced machine-learning-based steganalysis algorithms. The concept of steganography without embedding (SWE), which does not need to modify the data of the carrier image, appeared to overcome the detection of machine-learning-based steganalysis algorithms. In this paper, we propose a novel image SWE method based on deep convolutional generative adversarial networks. We map the secret information into a noise vector and use the trained generator neural network model to generate the carrier image based on the noise vector. No modification or embedding operations are required during the process of image generation, and the information contained in the image can be extracted successfully by another neural network, called the extractor, after training. The experimental results show that this method has the advantages of highly accurate information extraction and a strong ability to resist detection by state-of-the-art image steganalysis algorithms.

Cryptography is a widespread technique that maintains information security over insecure networks. The symmetric encryption scheme provides a good security, but the key exchange is difficult on the other hand, in the asymmetric encryption scheme, key management is easier, but it does not offer the same degree of security compared to symmetric scheme. A hybrid cryptosystem merges the easiness of the asymmetric schemes key distribution and the high security of symmetric schemes. In the proposed hybrid cryptosystem, Serpent algorithm is used as a data encapsulation scheme and Elliptic Curve Cryptography (ECC) is used as a key encapsulation scheme to achieve key generation and distribution within an insecure channel. This modification is done to tackle the issue of key management for Serpent algorithm, so it can be securely used in multimedia protection.

Visible light communications is an emerging architecture with unlicensed and huge bandwidth resources, security, and experimental implementations and standardization efforts. Display based transmitter and camera based receiver architectures are alternatives for device-to-device (D2D) and home area networking (HAN) systems by utilizing widely available TV, tablet and mobile phone screens as transmitters while commercially available cameras as receivers. Current architectures utilizing data hiding and unobtrusive steganography methods promise data transmission without user distraction on the screen. however, current architectures have challenges with the limited capability of data hiding in translucency or color shift based methods of hiding by uniformly distributing modulation throughout the screen and keeping eye discomfort at an acceptable level. In this article, foveation property of human visual system is utilized to define a novel modulation method denoted by FoVLC which adaptively improves data hiding capability throughout the screen based on the current eye focus point of viewer. Theoretical modeling of modulation and demodulation mechanisms hiding data in color shifts of pixel blocks is provided while experiments are performed for both FoVLC method and uniform data hiding denoted as conventional method. Experimental tests for the simple design as a proof of concept decreases average bit error rate (BER) to approximately half of the value obtained with the conventional method without user distraction while promising future efforts for optimizing block sizes and utilizing error correction codes.

Due to improvements in defensive systems, network threats are becoming increasingly sophisticated and complex as cybercriminals are using various methods to cloak their actions. This, among others, includes the application of network steganography e.g. to hide the communication between an infected host and a malicious control server by embedding commands into innocent-looking traffic. Currently, a new subtype of such methods called inter-protocol steganography emerged. It utilizes relationships between two or more overt protocols to hide data. In this paper, we present new inter-protocol hiding techniques which are suitable for real-time services. Afterwards, we introduce and present preliminary results of a novel steganography detection approach which relies on network traffic coloring.

Detection and prevention of data breaches in corporate networks is one of the most important security problems of today's world. The techniques and applications proposed for solution are not successful when attackers attempt to steal data using steganography. Steganography is the art of storing data in a file called cover, such as picture, sound and video. The concealed data cannot be directly recognized in the cover. Steganalysis is the process of revealing the presence of embedded messages in these files. There are many statistical and signature based steganalysis algorithms. In this work, the detection of steganographic images with steganalysis techniques is reviewed and a system has been developed which automatically detects steganographic images in network traffic by using open source tools.

Rootkits detecting in the Windows operating system is an important part of information security monitoring and audit system. Methods of hided process detection were analyzed. The software is developed which implements the four methods of hidden process detection in a user mode (PID based method, the descriptor based method, system call based method, opened windows based method) to use in the monitoring and audit systems.

Steganography is the science of hiding information to send secret messages using the carrier object known as stego object. Steganographic technology is based on three principles including security, robustness and capacity. In this paper, we present a digital image hidden by using the compressive sensing technology to increase security of stego image based on human visual system features. The results represent which our proposed method provides higher security in comparison with the other presented methods. Bit Correction Rate between original secret message and extracted message is used to show the accuracy of this method.

Audio Steganography is the technique of hiding any secret information behind a cover audio file without impairing its quality. Data hiding in audio signals has various applications such as secret communications and concealing data that may influence the security and safety of governments and personnel and has possible important applications in 5G communication systems. This paper proposes an efficient secure steganography scheme based on the high correlation between successive audio signals. This is similar to the case of differential pulse coding modulation technique (DPCM) where encoding uses the redundancy in sample values to encode the signals with lower bit rate. Discrete Wavelet Transform (DWT) of audio samples is used to store hidden data in the least important coefficients of Haar transform. We use the benefit of the small differences between successive samples generated from encoding of the cover audio signal wavelet coefficients to hide image data without making a remarkable change in the cover audio signal. instead of changing of actual audio samples so this doesn't perceptually degrade the audio signal and provides higher hiding capacity with lower distortion. To further increase the security of the image hiding process, the image to be hidden is divided into blocks and the bits of each block are XORed with a different random sequence of logistic maps using hopping technique. The performance of the proposed algorithm has been estimated extensively against attacks and experimental results show that the proposed method achieves good robustness and imperceptibility.