Jawad Ahmad

A compression sensing and noise-tolerant image encryption scheme based on chaotic maps and orthogonal matrices

Abstract With the evolution of technologies, the size of an image data has been significantly increased. However, traditional image encryption schemes cannot handle the emerging problems in big data such as noise toleration and compression. In order to meet today’s challenges, we propose a new image encryption scheme based on chaotic maps and orthogonal matrices. The main core of the proposed scheme is based on the interesting properties of an orthogonal matrix. To obtain a random orthogonal matrix via the Gram Schmidt algorithm, a well-known nonlinear chaotic map is used in the proposed scheme to diffuse pixels values of a plaintext image. In the process of block-wise random permutation, the logistic map is employed followed by the diffusion process. The experimental results and security analyses such as key space, differential and statistical attacks show that the proposed scheme is secure enough and robust against channel noise and JPEG compression. In addition to complete encryption for higher security, it also supports partial encryption for faster processing as well.

A new chaos-based secure image encryption scheme using multiple substitution boxes

Due to development in Internet and networking technology, multimedia data is broadly transmitted via wired and wireless medium. Thus security is a major concern in modern communication systems. Encryption is one of the pre-eminent ways to guarantee security in many real time applications. In this paper, confusion and diffusion phenomenon is presented for digital images. The proposed scheme provides a secure image encryption/decryption scheme using two chaotic maps and substitution boxes. To confuse the relationship between plaintext and ciphertext images, both chaotic maps play a vital role in the confusion and diffusion process. In confusion process, the plaintext image is permuted row-wise and column-wise via two random sequences generated by Henon map. The pixel values diffusion is carried out by unimodel Skew tent map through XOR operation. Furthermore, in last step of the proposed scheme, image is divided into four blocks. To get a highly diffused ciphertext, four different Substitution Boxes (S-Boxes) are applied on each block. Extensive security analysis show that the proposed scheme provides an efficient security for digital images.

Comparative analysis of chaotic and non-chaotic image encryption schemes

In modern era, multimedia technologies have been developed significantly. Multimedia data such as audio, video and image transfers over the internet is open and insecure. Security is required for storage and transmission of digital images to avoid from unauthorized entities. A number of encryption schemes have been developed for security of multimedia data over insecure channel. So, there is a real need to compare encryption schemes that which technique is better for multimedia application. This paper presents the estimation for the good image encryption algorithm. Chaos based image encryption algorithm are used now a days because of better security and good performance. Behaviour of chaotic system is nonlinear, deterministic and sensitive to initial condition. A number of parameters, like correlation coefficient, information entropy, compression friendliness, number of pixels change rate, average intensity and unified average change intensity etc., are used to check the quality of cipher-text image. This work is review of two image encryption schemes, namely Compression Friendly Encryption Scheme (CFES) and Chaos Based Encryption Scheme (CBES).

A novel image encryption scheme based on orthogonal matrix, skew tent map, and XOR operation

Content protection is considered as an important issue in today’s world. Therefore, encryption of such contents is a challenging task for researchers. They are focusing on protection of valuable data such as image, video, and audio against different attacks from eavesdroppers. In this paper, we proposed an enhanced version of Fawad et al.’s scheme to fulfill essential needs of a secure image encryption algorithm. The proposed cryptosystem is resistant against many attacks like brute force, differential and statistical. To quantify the quality of the proposed scheme, instead of visual inspection, the proposed scheme is analyzed through various tests, such as correlation coefficient, information entropy, Number of Pixel Change Rate (NPCR) and Unified Average Change Intensity (UACI). Simulation results of the presented scheme shows good diffusion characteristics when compared to other traditional schemes.

An efficient and secure partial image encryption for wireless multimedia sensor networks using discrete wavelet transform, chaotic maps and substitution box

Abstract Wireless Sensor Networks (WSN) is widely deployed in monitoring of some physical activity and/or environmental conditions. Data gathered from WSN is transmitted via network to a central location for further processing. Numerous applications of WSN can be found in smart homes, intelligent buildings, health care, energy efficient smart grids and industrial control systems. In recent years, computer scientists has focused towards findings more applications of WSN in multimedia technologies, i.e. audio, video and digital images. Due to bulky nature of multimedia data, WSN process a large volume of multimedia data which significantly increases computational complexity and hence reduces battery time. With respect to battery life constraints, image compression in addition with secure transmission over a wide ranged sensor network is an emerging and challenging task in Wireless Multimedia Sensor Networks. Due to the open nature of the Internet, transmission of data must be secure through a process known as encryption. As a result, there is an intensive demand for such schemes that is energy efficient as well as highly secure since decades. In this paper, discrete wavelet-based partial image encryption scheme using hashing algorithm, chaotic maps and Hussain’s S-Box is reported. The plaintext image is compressed via discrete wavelet transform and then the image is shuffled column-wise and row wise-wise via Piece-wise Linear Chaotic Map (PWLCM) and Nonlinear Chaotic Algorithm, respectively. To get higher security, initial conditions for PWLCM are made dependent on hash function. The permuted image is bitwise XORed with random matrix generated from Intertwining Logistic map. To enhance the security further, final ciphertext is obtained after substituting all elements with Hussain’s substitution box. Experimental and statistical results confirm the strength of the anticipated scheme.

A novel image encryption based on Lorenz equation, Gingerbreadman chaotic map and S 8 permutation

Internet is used as the main source of communication throughout the world. However due to public nature of internet data are always exposed to different types of attacks. To address this issue many researchers are working in this area and proposing data encryption techniques. Recently a new substitution box has been proposed for image encryption using many interesting properties like gingerbread-man chaotic map and S8 permutation. But there are certain weaknesses in aforesaid technique which does not provide sufficient security. To resolve the security issue an enhanced version of existing technique is proposed in this paper. Lorenz chaotic map based confusion and diffusion processes in existing technique are employed. Lorenz map is used to remove strong correlation among the plain text image pixels. In diffusion stage a random matrix is generated through lorenz chaotic map and XORed with shuffled image. It the end, existing gingerbread-man chaotic map based S-box is applied to extract the final cipher text image. The proposed enhanced scheme is analysed by statistical analysis, key space analysis, information entropy analysis and differential analysis. In order to ensure the robustness and higher security of proposed scheme, results via Number of Pixel Rate Change (NPRC)and Unified Average Change Intensity (UACI) tests are also validated. 9

Secure speech communication algorithm via DCT and TD-ERCS chaotic map

Secure communication has always been a demanding area in civil, commercial and particularly in military set up. Robust and time-tested efficient algorithms are needed to have an essential privacy for speech transmission in the telephone networks, radio communication and in the emerging cellular mobile radio systems. In this paper, we present a highly secure speech encryption algorithm based on amplitude scrambling and Discrete Cosine Transform (DCT) coefficients scrambling. The permutation is performed using TD-ERCS chaotic map. The proposed scheme has been implemented successfully on software framework which yielded zero residual intelligibility and high quality of recovered speech. Simulation results reveal that the anticipated algorithm is secure enough and resistant against various security attacks. The authors are reasonably confident of their contribution which can eventually be exploited as software, hardware-software and an integral part of any embedded secure communication system.

Real-time object detection and tracking

Real-time object detection and tracking is a vast, vibrant yet inconclusive and complex area of computer vision. Due to its increased utilization in surveillance, tracking system used in security and many others applications have propelled researchers to continuously devise more efficient and competitive algorithms. However, problems emerge in implementing object detection and tracking in real-time; such as tracking under dynamic environment, expensive computation to fit the real-time performance, or multi-camera multi-objects tracking make this task strenuously difficult. Though, many methods and techniques have been developed, but in this literature review we have discussed some famous and basic methods of object detection and tracking. In the end we have also given their general applications and results.