Asymmetric Image Encryption based on Cipher Matrices

In most of the cryptological methods, the encrypted data or the cipher texts maintain same statistics of the plain texts, whereas matrix encryption method does not keep the statistics of individual cipher texts. However, it maintains the statistics of block of characters of size m where m is the size of the key matrix. One of the important features of the cipher matrix in Residue Number System (RNS) is that it is highly dicult and time consuming to obtain its inverse by standard inverse algorithms. Matrix in RNS does not have all the eigen values as dened in complex eld. The eigen factors of a matrix is dened as the irreducible factors of the characteristic equation(eigen function). All the above properties are valid for cipher matrix in Galois Field. The public key is generated by using two types of matrices. One of these matrices is a self-invertible matrix or an orthonormal matrix in Galois eld whereas the other matrix is a diagonally dominant matrix. Matrix inversion is very dicult and time consuming when size of matrix and modulo number are large. The computational overhead in generalized Hill cipher can be reduced substantially by using self-invertible matrices. Self-invertible ma- trices uses less space compared to invertible matrices. In order to overcome this problem, p(modulo) is made very large so that there would be at least pn=2 possible matrices making it extremely dicult for the intruder to nd the key matrix. In this thesis several methods of generating self-invertible matrix are proposed. Orthogonal Transform is used in signal processing. Modular Orthogonal Trans- form such as Walsh, Hadamard, Discrete Cosine Transform, Discrete Sine Trans- form, Discrete Fourier Transform have been used for encryption of image. The orthogonal matrices can be used as asymmetric key for encryption. In this work various methods of generating orthogonal matrices have been proposed. Matrix having primitive polynomial as eigen factors is used resulting in robust encryp- tion. A novel operation called exponentiation and its inverse has been dened in this thesis. All the properties of this new operation have been analyzed in Zp. This operation is used for encryption of image. The original image can be obtained by using the same exponentiation operation. Chaotic sequence and chaotic signal generation is widely used in communica- tion. Two stages of image encryption scheme using chaotic sequence is proposed in this work. First stage of encryption by chaotic sequence generated in GF(p) and the second stge of encryption is carried out by one of the encryption methods discussed in the previous chapters. Standard images have been used for encryption during simulation. Keywords: Encryption, Decryption, Cipher matrix, Public key, Private key, Residue number system, Eigen function, self-invertible matrix, Orthogonal, Ga- lois Field, Exponentiation, Chaotic sequence

Mobile-based Telemedicine Application using SVD and F-XoR Watermarking for Medical Images

منصة الخدمات الطبية عبارة عن تطبيق متنقل يتم من خلاله تزويد المرضى بتشخيصات الأطباء بناءً على المعلومات المستقاة من الصور الطبية. يجب ألا يتم تبديل محتوى هذه النتائج التشخيصية بشكل غير قانوني أثناء النقل ويجب إعادته إلى المريض الصحيح. في هذه المقالة، نقدم حلاً لهذه المشكلات باستخدام علامة مائية عمياء وقابلة للانعكاس وهشة استنادًا إلى مصادقة صورة المضيف. في الخوارزمية المقترحة، يتم استخدام الإصدار الثنائي من ترميز بوس_شوهوري _هوكوينجهام (BCH) للتقرير الطبي للمريض (PMR) والصورة الطبية الثنائية للمريض (PMI) بعد استخدام الغامض الحصري أو (F-XoR) لإنتاج العلامة الفريدة للمريض باستخدام مخطط المشاركة السرية (SSS). يتم استخدامه لاحقًا كعلامة مائية ليتم تضمينها في مضيف (PMI) باستخدام خوارزمية تحليل القيمة المفرد (SVD) العمياء القائمة على العلامة المائية. وهو حل جديد اقترحناه أيضًا بتطبيق SVD على صورة العلامة المائية العمياء. تحافظ الخوارزمية الخاصة بنا على مصادقة محتوى (PMI) أثناء النقل وملكية (PMR) للمريض لنقل التشخيص المصاحب فيما بعد إلى المريض الصحيح عبر تطبيق التطبيب عن بعد المحمول. يستخدم تقييم الخوارزمية لدينا علامات مائية مسترجعة توضح النتائج الواعدة لمقاييس الأداء العالية مقارنتا مع نتائج الاعمال السابقة في مقاييس الكشف عن التزوير وإمكانية الاسترداد الذاتي، مع قيمة 30NB PSNR، قيمة NC هي 0.99.A medical- service platform is a mobile application through which patients are provided with doctor’s diagnoses based on information gleaned from medical images. The content of these diagnostic results must not be illegitimately altered during transmission and must be returned to the correct patient. In this paper, we present a solution to these problems using blind, reversible, and fragile watermarking based on authentication of the host image. In our proposed algorithm, the binary version of the Bose_Chaudhuri_Hocquengham (BCH) code for patient medical report (PMR) and binary patient medical image (PMI) after fuzzy exclusive or (F-XoR) are used to produce the patient's unique mark using secret sharing schema (SSS). The patient’s unique mark is used later as a watermark to be embedded into host PMI using blind watermarking-based singular value decomposition (SVD) algorithm. This is a new solution that we also proposed to applying SVD into a blind watermarking image. Our algorithm preserves PMI content authentication during the transmission and PMR ownership to the patient for subsequently transmitting associated diagnosis to the correct patient via a mobile telemedicine application. The performance of experimental results is high compare to previous results, uses recovered watermarks demonstrating promising results in the tamper detection metrics and self-recovery capability, with 30db PSNR, NC value is 0.99

Biometrics for internet‐of‐things security: A review

The large number of Internet‐of‐Things (IoT) devices that need interaction between smart devices and consumers makes security critical to an IoT environment. Biometrics offers an interesting window of opportunity to improve the usability and security of IoT and can play a significant role in securing a wide range of emerging IoT devices to address security challenges. The purpose of this review is to provide a comprehensive survey on the current biometrics research in IoT security, especially focusing on two important aspects, authentication and encryption. Regarding authentication, contemporary biometric‐based authentication systems for IoT are discussed and classified based on different biometric traits and the number of biometric traits employed in the system. As for encryption, biometric‐cryptographic systems, which integrate biometrics with cryptography and take advantage of both to provide enhanced security for IoT, are thoroughly reviewed and discussed. Moreover, challenges arising from applying biometrics to IoT and potential solutions are identified and analyzed. With an insight into the state‐of‐the‐art research in biometrics for IoT security, this review paper helps advance the study in the field and assists researchers in gaining a good understanding of forward‐looking issues and future research directions

Scaling Factor Threshold Estimator in Different Color Models Using a Discrete Wavelet Transform for Steganographic Algorithm

Two of the main problems with steganographic algorithms are insertion capability and minimization of distortion in the digital files where the hidden information is the information is inserted to hiding Digital filters are generally used as noise detectors, and they also suppress information outside the original information contained in the file. There are different types of filtering, one in the spatial domain and the other in the frequency domain or sometimes a combination of both domains to propose adaptive filters. One of the filters with greater application is the discrete wavelet transform (DWT) because it is easy to implement and has low computational complexity. The DWT computationally implemented in an image can be represented as a quadrature mirror filter, separating the frequency components: so high-high, high-low, low-high and low-low levels obtain different resolutions

Applied public-key steganography

International audienceWe consider the problem of hiding information in a steganographic framework, i.e. embedding a binary message within an apparently innocuous content, in order to establish a `suspicion-free' digital communication channel. The adversary is passive as no intentional attack is foreseen. The only threat is that she discovers the presence of a hidden communication. The main goal of this article is to find if the calar Costa Scheme, a recently published embedding method exploiting side information at the encoder, is suitable for that framework. We justify its use assessing its security level with respect to the Cachin's criterion. We derive a public-key stegosystem following the ideas of R. Anderson and P. Petitcolas. This technique is eventually applied to PCM audio contents. Experimental performances are detailed in terms of bit-rate and Kullback-Leibler distance

Multibiometric security in wireless communication systems

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University, 05/08/2010.This thesis has aimed to explore an application of Multibiometrics to secured wireless communications. The medium of study for this purpose included Wi-Fi, 3G, and WiMAX, over which simulations and experimental studies were carried out to assess the performance. In specific, restriction of access to authorized users only is provided by a technique referred to hereafter as multibiometric cryptosystem. In brief, the system is built upon a complete challenge/response methodology in order to obtain a high level of security on the basis of user identification by fingerprint and further confirmation by verification of the user through text-dependent speaker recognition. First is the enrolment phase by which the database of watermarked fingerprints with memorable texts along with the voice features, based on the same texts, is created by sending them to the server through wireless channel. Later is the verification stage at which claimed users, ones who claim are genuine, are verified against the database, and it consists of five steps. Initially faced by the identification level, one is asked to first present one’s fingerprint and a memorable word, former is watermarked into latter, in order for system to authenticate the fingerprint and verify the validity of it by retrieving the challenge for accepted user. The following three steps then involve speaker recognition including the user responding to the challenge by text-dependent voice, server authenticating the response, and finally server accepting/rejecting the user. In order to implement fingerprint watermarking, i.e. incorporating the memorable word as a watermark message into the fingerprint image, an algorithm of five steps has been developed. The first three novel steps having to do with the fingerprint image enhancement (CLAHE with 'Clip Limit', standard deviation analysis and sliding neighborhood) have been followed with further two steps for embedding, and extracting the watermark into the enhanced fingerprint image utilising Discrete Wavelet Transform (DWT). In the speaker recognition stage, the limitations of this technique in wireless communication have been addressed by sending voice feature (cepstral coefficients) instead of raw sample. This scheme is to reap the advantages of reducing the transmission time and dependency of the data on communication channel, together with no loss of packet. Finally, the obtained results have verified the claims

Data Hiding and Its Applications

Data hiding techniques have been widely used to provide copyright protection, data integrity, covert communication, non-repudiation, and authentication, among other applications. In the context of the increased dissemination and distribution of multimedia content over the internet, data hiding methods, such as digital watermarking and steganography, are becoming increasingly relevant in providing multimedia security. The goal of this book is to focus on the improvement of data hiding algorithms and their different applications (both traditional and emerging), bringing together researchers and practitioners from different research fields, including data hiding, signal processing, cryptography, and information theory, among others

Simple and secured access to networked home appliances via internet using SSL, BioHashing and single Authentication Server

This thesis describes a web-based application that will enable users to access their networked home appliances over the Internet in an easy, secured, accessible and cost effective manner, using the user's iris image only for authentication. As Internet is increasingly gaining significance and popularity in our daily lives, various home networking technologies also started gaining importance from consumers, which helped in facilitating interoperability, sharing of services and exchange of information between different electronic devices at home. As a result, the demand to be able to access home appliances or security cameras over the Internet gradually grew. In this research, we propose an efficient, secured, low-cost and user-friendly method to access networked home appliances over the Internet, providing strong, well integrated, three levels of security to the whole application and user data. According to our design, the user's iris data after hashing (using BioHashing) is sent through a secure communication channel utilizing Secure Sockets Layer v-3.0. The deterministic feature sequence from the iris image is extracted using 1D log-Gabor filters and while performing BioHashing, the orthonormalization of the pseudorandom number is implemented employing Gram-Schmidt orthonormalization algorithm. In addition to this protected data transfer mechanism, we propose the design of an Authentication Server that can be shared among multiple homes, allowing numerous users to access their home appliances in a trouble-free and secured manner. It can also bring down the cost of commercial realization of this endeavor and increase its accessibility without compromising on system security. We demonstrate that the recognition efficiency of this system is computationally effective with equal error rate (EER) of 0% and 6.75% (average) in two separate conditions on CASIA 1 and CASIA 2 iris image datasets

Recent Application in Biometrics

In the recent years, a number of recognition and authentication systems based on biometric measurements have been proposed. Algorithms and sensors have been developed to acquire and process many different biometric traits. Moreover, the biometric technology is being used in novel ways, with potential commercial and practical implications to our daily activities. The key objective of the book is to provide a collection of comprehensive references on some recent theoretical development as well as novel applications in biometrics. The topics covered in this book reflect well both aspects of development. They include biometric sample quality, privacy preserving and cancellable biometrics, contactless biometrics, novel and unconventional biometrics, and the technical challenges in implementing the technology in portable devices. The book consists of 15 chapters. It is divided into four sections, namely, biometric applications on mobile platforms, cancelable biometrics, biometric encryption, and other applications. The book was reviewed by editors Dr. Jucheng Yang and Dr. Norman Poh. We deeply appreciate the efforts of our guest editors: Dr. Girija Chetty, Dr. Loris Nanni, Dr. Jianjiang Feng, Dr. Dongsun Park and Dr. Sook Yoon, as well as a number of anonymous reviewers