A Study of Z-Transform Based Encryption Algorithm

It has become increasingly important to ensure the protection of information, especially data in transit. Therefore, it is the primary goal of any encryption algorithm to safeguard the protection of information against security attacks. It is equally important to design high-performance solutions with affordable cost of implementation. Encryption algorithms are used to transform plain text to the ciphertext in order to protect privacy, prevent data fraud, and prevent unauthorized access of data in daily transactions. There are multiple types of encryption algorithms, each with its niche tactics to enhance security. For instance, different kinds of algorithms include but are not limited to the following: Blowfish, RSA, AES, DES, Triple DES. This paper contributes an efficient and secure encryption algorithm technique for information security based on Z transformation and XOR function known as the Z Transformation Encryption (ZTE) technique. To elaborate, this technique implements concepts of Z transformation and XOR operations at the source. The reverse process is applied at the receiving end of the transaction wherein the inverse of Z transformation and XOR is applied to reveal the original plain text message. The simulation of the proposed algorithm is conducted using the R language. The results show a promising performance comparing to other symmetric algorithms

Modified algorithm for image watermarking using 2D-DCT and elgamal cryptosystem / Nur Azien Yazid, Kamilah Abdullah and Suhaila Abd Halim

Image watermarking embeds identifying information in an image in such a manner that it cannot easily be removed. For the past several years, image digital watermarking has become a necessary element used for hid ing secret image and enabling secured communication such as privacy, confidentiality, authentication and data integrity. Although numerous watermarking schemes are present in grayscale images, the present work focuses on the RGB color image. This study proposed a new hybrid method that would satisfy the essential needs of modern image watermarking. The color image watermarking is based on the 2D Discrete Cosine Transform and Egamal cryptosystem.The 2D Discrete Cosine Transform depends on the matrix products, while the ElGamal cryptosystem depends on the discrete logarithm problem. The cryptosystem is combined with existing Arnold transform in watermarking algorithm to enhance the security of secret image. Value of Peak Signal to Noise Ratio was taken as performance evaluation parameters. On the whole, the performance evaluation shows that combining the two algorithms improved the performance of image watermarking

A Comprehensive Review on Digital Image Watermarking

The advent of the Internet led to the easy availability of digital data like images, audio, and video. Easy access to multimedia gives rise to the issues such as content authentication, security, copyright protection, and ownership identification. Here, we discuss the concept of digital image watermarking with a focus on the technique used in image watermark embedding and extraction of the watermark. The detailed classification along with the basic characteristics, namely visual imperceptibility, robustness, capacity, security of digital watermarking is also presented in this work. Further, we have also discussed the recent application areas of digital watermarking such as healthcare, remote education, electronic voting systems, and the military. The robustness is evaluated by examining the effect of image processing attacks on the signed content and the watermark recoverability. The authors believe that the comprehensive survey presented in this paper will help the new researchers to gather knowledge in this domain. Further, the comparative analysis can enkindle ideas to improve upon the already mentioned techniques

Review of Watermarking and Color Image Retrieval

The development of information technology and network technology is increasing rapidly. In network technology, multimedia communication applications are used in various formats such as text, image, audio and video. These formats are spreading very fast over the internet without any security and they can be easily copied by anyone without any prior protection and their feature can be easily copied. Nowadays the copyright infringement and piracy become very serious problem. Because of this problem, watermarking technology is used to protect the color image. In a recent year, several watermarking techniques are available such as spatial watermarking technique and frequency based watermarking technique. Frequency watermarking technique is used to differentiate the transformation of the wave and the discrete cosine transformation but transform watermarking techniques cannot provide adequate protection of image or data. This provides a weak answer to the problem of geometrical attack such as noise attack, rotation attack and translation attack. Therefore the use of spatial watermarking technique is recommended through the use of least significant bits, patch work and coding to reduce the problem of geometrical attack. This technique is comparatively simple. It can survive simple operations such as cutting and adding noise. In this document, we propose the watermark scheme based on spatial domain for color images. This scheme uses the Sobel and Canny edge detection methods to determine border information of the Luminance and chrominance components of the color image

An Experimental Approach for Encryption and Decryption of Image using Canonical Transforms & Scrambling Technique

Data security is a prime objective of various researchers & organizations. Because we have to send the data from one end to another end so it is very much important for the sender that the information will reach to the authorized receiver & with minimum loss in the original data. Data security is required in various fields like banking, defense, medical etc. So our objective here is that how to secure the data. This study is performed on MATLAB R2016b with standard databasegrey scale images like Barbara, Cameraman and Lenna or by using the personalize images in standard format. First of all, the images are scrambled and then the generation of a new complex image took place. Initially phase mask is applied on the complex image by using RPM 1, and then the complex image is encrypted by using LCT of first order. Again the phase mask RPM 2 is applied on the encrypted image followed by the LCT of second order to get the encrypted image finally. Reverse process is applied to get the original image. Various parameters are calculated which shows various aspects. Like Change in the value of MSE with change in order of transform tells the quality of encrypted image. Correlation coefficient of encrypted and decrypted image also shows the difference between the encrypted and decrypted image. The original image is then reconstructed and histogram of all these images analyzed. Robustness and imperceptibility of images increases by the proposed method

Iris Biometric Watermarking for Authentication Using Multiband Discrete Wavelet Transform and Singular-Value Decomposition

The most advanced technology, watermarking enables intruders to access the database. Various techniques have been developed for information security. Watermarks and histories are linked to many biometric techniques such as fingerprints, palm positions, gait, iris and speech are recommended. Digital watermarking is the utmost successful approaches among the methods available. In this paper the multiband wavelet transforms and singular value decomposition are discussed to establish a watermarking strategy rather than biometric information. The use of biometrics instead of conservative watermarks can enhance information protection. The biometric technology being used is iris. The iris template can be viewed as a watermark, while an iris mode of communication may be used to help information security with the addition of a watermark to the image of the iris. The research involves verifying authentication against different attacks such as no attacks, Jpeg Compression, Gaussian, Median Filtering and Blurring. The Algorithm increases durability and resilience when exposed to geometric and frequency attacks. Finally, the proposed framework can be applied not only to the assessment of iris biometrics, but also to other areas where privacy is critical

Integration of biometrics and steganography: A comprehensive review

The use of an individual’s biometric characteristics to advance authentication and verification technology beyond the current dependence on passwords has been the subject of extensive research for some time. Since such physical characteristics cannot be hidden from the public eye, the security of digitised biometric data becomes paramount to avoid the risk of substitution or replay attacks. Biometric systems have readily embraced cryptography to encrypt the data extracted from the scanning of anatomical features. Significant amounts of research have also gone into the integration of biometrics with steganography to add a layer to the defence-in-depth security model, and this has the potential to augment both access control parameters and the secure transmission of sensitive biometric data. However, despite these efforts, the amalgamation of biometric and steganographic methods has failed to transition from the research lab into real-world applications. In light of this review of both academic and industry literature, we suggest that future research should focus on identifying an acceptable level steganographic embedding for biometric applications, securing exchange of steganography keys, identifying and address legal implications, and developing industry standards

Quaternion-based Encryption/Decryption of Audio Signal Using Digital Image as Variable Key

With the rapid growth of communication technology, cryptography plays a significant role in securing and verification of information exchanged via public communication channels.   The current paper introduces a novel method for encrypting/decrypting audio signal using a selected digital image as a complicated key and cover for audio signal.  Each sample of the audio signal is combined with the values of the three color components of a pixel fetched from the cover image yielding a quaternion number.   The absolute value of this quaternion number is then transmitted and when received, the original value of the audio sample can be extracted using simple quaternion mathematics. A second level of complexity can be added to this approach by applying one of the well-known cryptographic techniques (symmetric or asymmetric).   The suggested approach is implemented using Matlab simulation software and the generated audio signal is compared with the original one using some performance metrics.  The obtained results show that the proposed approach is robust and more secure against cryptanalysis attacks