Survey on Biometric Image Sharing Using Cryptography and Diverse Image Media

Visual Secret Sharing Scheme is used to transmitting or delivering the secret images over the network. The VSS scheme has a major drawback that is it suffers from high transmission risk because the shares are like noise. As the shares are like noise that causes the attackers attention. In this paper we are using a natural-image based visual secret sharing (NVSS) scheme to reduce the transmission risk problem that occurs in VSS scheme. The NVSS scheme uses the natural images such as paintings, photographs etc as digital shares. As we are using the natural shares instead of noise like shares which reduces the transmission risk to certain limit. This scheme also uses the different media to transmit the shares

Emerging research directions in computer science : contributions from the young informatics faculty in Karlsruhe

In order to build better human-friendly human-computer interfaces, such interfaces need to be enabled with capabilities to perceive the user, his location, identity, activities and in particular his interaction with others and the machine. Only with these perception capabilities can smart systems ( for example human-friendly robots or smart environments) become posssible. In my research I\u27m thus focusing on the development of novel techniques for the visual perception of humans and their activities, in order to facilitate perceptive multimodal interfaces, humanoid robots and smart environments. My work includes research on person tracking, person identication, recognition of pointing gestures, estimation of head orientation and focus of attention, as well as audio-visual scene and activity analysis. Application areas are humanfriendly humanoid robots, smart environments, content-based image and video analysis, as well as safety- and security-related applications. This article gives a brief overview of my ongoing research activities in these areas

On security and privacy of consensus-based protocols in blockchain and smart grid

In recent times, distributed consensus protocols have received widespread attention in the area of blockchain and smart grid. Consensus algorithms aim to solve an agreement problem among a set of nodes in a distributed environment. Participants in a blockchain use consensus algorithms to agree on data blocks containing an ordered set of transactions. Similarly, agents in the smart grid employ consensus to agree on specific values (e.g., energy output, market-clearing price, control parameters) in distributed energy management protocols. This thesis focuses on the security and privacy aspects of a few popular consensus-based protocols in blockchain and smart grid. In the blockchain area, we analyze the consensus protocol of one of the most popular payment systems: Ripple. We show how the parameters chosen by the Ripple designers do not prevent the occurrence of forks in the system. Furthermore, we provide the conditions to prevent any fork in the Ripple network. In the smart grid area, we discuss the privacy issues in the Economic Dispatch (ED) optimization problem and some of its recent solutions using distributed consensus-based approaches. We analyze two state of the art consensus-based ED protocols from Yang et al. (2013) and Binetti et al. (2014). We show how these protocols leak private information about the participants. We propose privacy-preserving versions of these consensus-based ED protocols. In some cases, we also improve upon the communication cost

Efficient Random Grid Visual Cryptographic Schemes having Essential Members

In this paper we consider ``OR based monochrome random grid visual cryptographic schemes (RGVCS) for $t$-$(k,n)^*$ access structure which is a generalization of the threshold $(k,n)$ access structure in the sense that in all the successful attempts to recover the secret image, the $t$ essential participants must always be present. Up to the best of our knowledge, the current proposed work is the first in the literature of RGVCS which provides efficient direct constructions for the $t$-$(k,n)^*$-RGVCS for ``OR based model. Finding the closed form of light contrast is a challenging work. However, in this paper we come up with the closed form of the light contrast for the ``OR based model. In literature, there are visual cryptographic schemes where the secret reconstruction is done by binary ``XOR operation instead of ``OR operation to increase the relative contrast of the decoded image. In this paper, we also propose an extended grid based $t$-$(k,n)^*$-RGVCS in which we replace the traditional ``OR operation by ``XOR operation. Note that the use of XOR operation indicates that the decoding must be performed computationally and not visually. We justified our schemes using both experimental as well as simulation based data

Grid Analysis of Radiological Data

IGI-Global Medical Information Science Discoveries Research Award 2009International audienceGrid technologies and infrastructures can contribute to harnessing the full power of computer-aided image analysis into clinical research and practice. Given the volume of data, the sensitivity of medical information, and the joint complexity of medical datasets and computations expected in clinical practice, the challenge is to fill the gap between the grid middleware and the requirements of clinical applications. This chapter reports on the goals, achievements and lessons learned from the AGIR (Grid Analysis of Radiological Data) project. AGIR addresses this challenge through a combined approach. On one hand, leveraging the grid middleware through core grid medical services (data management, responsiveness, compression, and workflows) targets the requirements of medical data processing applications. On the other hand, grid-enabling a panel of applications ranging from algorithmic research to clinical use cases both exploits and drives the development of the services

A Visual Secret Sharing Technique for Secure and Fast Transmission of Image

ABSTRACT: In the advent of booming communication technology, the needs for information sharing and transfer have increased exponentially which requires more and more new techniques to meet the increasing needs of a modern society. Visual cryptography scheme is a cryptographic technique which allows visual information (e.g. printed text, handwritten notes, and picture) to be encrypted in such a way that the decryption can be performed by the human visual system, without the aid of computers. Random grid based technique is a non expanded visual cryptographic technique for generating both meaningless and noise like shares. In this paper the idea is to increase the levels of security and to enhance the transmission speed of secret information over the network, as the basic model of Visual Cryptography is not an efficient tool to hide the information. In the proposed scheme initially the image is encrypted by Visual Cryptography using Random Grids and we propose a technique using combined DCT based Compression with Steganography for the speed transmission and additional security of encrypted random image shares over the transmitting media. The experimental results demonstrate the feasibility of the proposed scheme. KEYWORDS: Visual cryptography; Compression; DCT; Random grid; Shares; Steganography I. INTRODUCTION In the recent communication technology, the needs for information exchange and transfer have increased exponentially. In the public domain the threat of an intruder accessing secret information has been an ever existing concern for the data communication. Steganography, Cryptography, and Visual cryptography are the most widely used techniques to overcome these threats. In Cryptography the plaintext is transformed (encrypting it) into an unreadable format, which is called as called cipher text. Only those who possess a secret key can decipher (or decrypt) the message into plain text. In steganography a message, image, or file is embedded within another message, image, or file. Both these techniques provide some level of security of data. In VC the image is encrypted by creating random shares and decryption is done by human eyes. However, neither of them alone is secure enough over an unsecure communication channel for sharing information and is vulnerable to intruder attacks. Although these techniques are often combined together to achieve higher levels of security, in order to minimize the threat of intrusion we still need a highly secured system to transfer information over any communication media. For any communication system, a secure transmission of information can be achieved using a powerful encoding algorithm and a fast transmission to send the information from a transmitter to a receiver (that can be done using an efficient compression technique) is two important requirements. To satisfy these constraints, we propose a new method of compression and encryption at same time. The image is initially encrypted by visual cryptography using random grid scheme by generating random shares. Then we cover the random share with a cover image. Our proposed method is based on the hiding of information (Embedding) in the transmitter side and taking out (Extracting) algorithm in receiver side the decoding phase. In addition we would like to compress the transmitting data, to achieve a high speed communication. For this purpose Discrete Cosine Transform (DCT) is utilized because most of the power is concentrated in the lower frequency bands by DCT, it is used to cut out the higher frequency components. Then the compressed DCT elements are rotated, the rotations have another aspect. The directions and degrees of the rotations are saved as "key" to restore the original images. If the receiver does not know "key," it is hard to recover the original images