Chaotic Encryption and Privilege Based Visual Secret Sharing Model for Color Images

In the Privilege-based Visual Secret Sharing Model (PVSSM), each share has a unique privilege and a higher-privilege share contributes with more privilege to reveal the secret image. However, in PVSSM, when several shares with the higher priority are stacked, the secret image can be visibly displayed. This security problem is solved by applying a two-dimensional Logistic-Adjusted Sine Map (2D-LASM) to each share. This method is called Chaotic Encryption-based PVSSM. In this paper, we aim to present how Chaotic Encryption-based PVSSM is applied to color images. In order to assess the efficiency of this method, histogram analysis, data loss attack, salt-pepper noise attack, differential attack, chi-square analysis and correlation analysis tests were applied. The performance of this method has been evaluated according to NCPR, UACI, PSNR, SSIM and CQM. The proposed method achieved a good test values and showed better results compared to similar studies in literature

Visual Cryptography and Steganography Methods - Review

In today’s information era information hiding becomes very much important as people transmits the information as innocent as credit card to online stores and as dangerous as terrorist plot to hijackers. The art of information hiding receive attention of the researchers. This paper provides a review of two methods – Visual Cryptography and Steganography for secure communication via a common communication channel. DOI: 10.17762/ijritcc2321-8169.16043

New Designs for Friendly Visual Cryptography Scheme

NSC101-2221-E-032-047[[abstract]]Different from conventional cryptography, visual cryptography is an image cryptographic technique proposed by Naor and Shamir. It encodes a secret image into n pieces of noise-like shares. When k or more than k pieces of shares are gathered from participants, human visual system will disclose the secret image on the stacked image easily. Neither complicated mathematical computation nor any knowledge of cryptography are needed are the main advantages of visual cryptography. In this paper, we propose a new design for friendly visual cryptography scheme. The secret will be hiding into two meaningful shares. The black-appearing ratio in each block of the shares for the corresponding black (rep. white) secret pixel is the same. Therefore, it is impossible for one to disclose any information related to the secret image on each share, which achieves the goal of improving security. When shares are superimposed, the contours of the cover image will disappear on the stacked image, which will only reveal the secret image. According to our experimental results, the contrasts of the shares or the stacked images are good which can reveal the contents of the cover images and the secret image clearly.[[notice]]補正完畢[[journaltype]]國外[[ispeerreviewed]]Y[[booktype]]紙本[[countrycodes]]SG

(N,N) Share Generation using Key Share approach for RGB image in VCS

Visual Cryptography is a secure and unique image encryption technique which protects image based secret. In visual cryptography image is encrypted into shares and in decryption process all or some of shares are super imposed with each other to decrypt the original secret image. In this technique no complex computation is needed for decryption of secret image which is the best advantage of Visual Cryptography Scheme. In this report various types of visual cryptographic techniques are discussed from previous research area. In this proposed system (N, N) VCS is used for encryption. It takes color image as an input and extracts in R, G and B components. After that it generates Key-Mask using Key-Mask generation algorithm which XOR-ed with R, G and B components and gives the key shares. Further XOR operation of these key shares with key mask generates the color shares. In decryption process image is recovered by XOR operation between key mask and color shares. It has a better security features compared to previous one

Bit Slicng based Visual Cryptography On Gray Scale ImageÂ

Data transmission through online is become mandatory in recent ages. No one can avoid data transmission over internet. But sensitivity of the data to be considered while transmits over internet. Internet is public medium where everyone has equal right to do their activities. Like in general public, internet also having malicious users and their main activity is deployment of attack. These attacks are of many types such as hacking, tampering and eavesdropping etc. Efficient data hiding techniques are required to with stand these attacks or to escape from these attacks. Visual Cryptography is one of such techniques to hide multimedia data in other multimedia data such as images, audio files or video files. In the proposed system secret image is partitioned or divided into shares based on the bits. These shares are then covered with given cover images then these covered shares are distributed to ‘n’ participants. To recover the secret all those participants are required. The proposed approach followed a novel method of bit slicing on gray scale images. So at the time of recover secret image cant’ be visible with same intensity or resolution as that of original image. For this purpose four secret keys are used. Simulation results shows that when compared to existing schemes , proposed approach can hide the image under cover images in efficient way as well as recovering of secret also lightweight and resilience to attacks

A Simple Scheme for Visual Cryptography

Here an algorithm is proposed to implement (2, 2) secret sharing problem which reduces the size (resolution) of the generated shares. Instead of considering one pixel at a time to generate the share, two consecutive pixels of the original image are considered row wise. Finally a pixel share having six pixels is generated for the considered two consecutive pixels. Thus we get six pixels instead of eight pixels in the shares corresponding to two pixels in the original image. As a result two pixels (8-6 = 2) in the share are reduced corresponding to two pixels of original image