Visual cryptography

About: Visual cryptography is a research topic. Over the lifetime, 1724 publications have been published within this topic receiving 25300 citations.

A Novel Image Steganography Technique for Secured Online Transaction Using DWT and Visual Cryptography

Abstract: Online payment eco system is the main target especially for cyber frauds. Therefore end to end encryption is very much needed in order to maintain the integrity of secret information related to transactions carried online. With access to payment related sensitive information, which enables lot of money transactions every day, the payment infrastructure is a major target for hackers. The proposed system highlights, an ideal approach for secure online transaction for fund transfer with a unique combination of visual cryptography and Haar based discrete wavelet transform steganography technique. This combination of data hiding technique reduces the amount of information shared between consumer and online merchant needed for successful online transaction along with providing enhanced security to customer's account details and thereby increasing customer's confidence preventing "Identity theft" and "Phishing". To evaluate the effectiveness of proposed algorithm Root mean square error, Peak signal to noise ratio have been used as evaluation parameters

Modified Visual Cryptography Scheme for Colored Secret Image Sharing

Abstract: Intent of this paper is to prove the better performance of the XOR Based visual cryptography schemes and traditional VCS on the basis of quality of reconstructed image and type of shares generated for colored images. The visual cryptography scheme (VCS) is a scheme which encodes a secret image into several shares. Here we are working with (2, 2) VCS. XOR-Based visual cryptography is capable to overcome the drawbacks of the visual cryptography scheme (VCS) the small contrast of the recovered secret image.

A visual cryptographic scheme for owner authentication using embedded shares

Abstract: A new scheme for user authentication is proposed using visual cryptography and digital watermarking. The original image, mostly the photograph of the authorized person is split into shares. One of the shares is kept within the server and the other one will be printed on the identification card issued to the user. The personal information unique to the user along with his signature will be embedded within the printed share. Least significant bit watermark insertion algorithm has been used for embedding data. Experiments show that the method is efficient and effective. It was possible to retrieve the watermark information from the printed share read through a reading device with no distortion. The method can be implemented with minimum processing cost.

A new color image sharing scheme with natural shadows

Abstract: Conventional visual secret sharing (VSS) schemes generate noise-like random pixels on shares to hide secret images. However, these schemes suffer from two problems, one related to security and one related to management. First, the noise-like shares arouse suspicion, which leads to security problems for participants who are involved in a VSS scheme. Second, participants cannot visually identify each share, especially if they hold more than one share simultaneously, which leads to the management problem. To address the management problem previous researchers developed extended visual cryptography schemes that add a meaningful cover image on each share. Generally, however, these approaches introduce a more serious pixel expansion problem than conventional VSS schemes. In addition, there are still many noise-like shares, which do not effectively reduce the security problems. This paper proposes a natural-image-based secret image sharing scheme (NSISS) that can share a color secret image over n − 1 arbitrary natural images and one noise-like share image. Instead of altering the contents of the natural images, the encryption process extracts feature images from each natural image. In such a way, the unaltered natural images are innocuous, thus greatly reducing the security problem. Experimental results indicate that the proposed approach is an excellent solution for solving the management and security problems. Moreover, the proposed approach avoids the pixel expansion problem and makes it possible to totally recover the secret images.

A novel 3–4 image secret sharing scheme

Abstract: (k, n) image secret sharing involves sharing of a secret image into n number of pieces called shadow images in such a way that k or more number of shares can retrieve the original image. In this paper we have proposed a (3, 4) image secret sharing scheme. The proposed method has adopted the concept of visual cryptography over the 2 × 2 block. The blocks are scrambled using pseudo random sequence to hence the security level. Proposed method requires less mathematical calculation than some existing techniques and does not need to make the size of the original image public.