scholarly journals A (k, n)-Threshold Progressive Visual Secret Sharing without Expansion

Cryptography ◽  
2018 ◽  
Vol 2 (4) ◽  
pp. 28
Author(s):  
Ying-Yu Chen ◽  
Bo-Yuan Huang ◽  
Justie Juan
Keyword(s):  
Secret Sharing ◽  
Visual Cryptography ◽  
Original Image ◽  
Visual Secret Sharing ◽  
Pixel Expansion ◽  
Threshold Secret Sharing ◽  
Secret Image ◽  
Sharing Scheme ◽  
Progressive Visual Secret Sharing ◽  
Positive Integers

Visual cryptography (VC) encrypts a secret image into n shares (transparency). As such, we cannot see any information from any one share, and the original image is decrypted by stacking all of the shares. The general (k, n)-threshold secret sharing scheme (SSS) can similarly encrypt and decrypt the original image by stacking at least k (≤ n) shares. If one stack is fewer than k shares, the secret image is unrecognizable. Another subject is progressive visual secret sharing, which means that when more shares are progressively stacked, the combined share becomes clearer. In this study, we constructed an advanced scheme for (k, n)-threshold SSS that can be encrypted in VC for any positive integers n ≥ k ≥ 2 through the method of combination, and the size of each share is the same as that of the original image. That is, no pixel expansion is required. Our scheme is novel, and the results from the theoretical analysis and simulation reveal that our scheme exhibits favorable contrast to that of other related schemes.

Cheating Prevention Method in Visual Cryptography by Using Random Grids

2013 ◽  
Vol 416-417 ◽  
pp. 1423-1428
Author(s):  
Hong Wei Lin ◽  
Xue Song Yang ◽  
Shu Wen Wang
Keyword(s):  
Secret Sharing ◽  
Visual Cryptography ◽  
Visual Secret Sharing ◽  
Pixel Expansion ◽  
Random Grids ◽  
Secret Image ◽  
Prevention Method

The traditional cheating prevention is usually based on visual cryptography (VC), in which the constructed image is bigger than the secret image because of the pixel expansion. In this paper, we studied the cheating problems in visual secret sharing (VSS) by random grids (RG) which can prevent the cheating activities with no pixel expansion. We considered the attacks of collusive cheaters who may deviate from the scheme in any way. We presented the cheating method and applied it on attacking existent n-out-of-n VSS scheme based on RG. Then we proposed one cheat-preventing scheme that can prevent the cheating activity upon.

scholarly journals A New Bi-Level Encoding and Decoding Scheme for Pixel Expansion Based Visual Cryptography

2019 ◽  
Vol 6 (1) ◽  
pp. 18-42
Author(s):  
Ram Chandra Barik ◽  
Suvamoy Changder ◽  
Sitanshu Sekhar Sahu
Keyword(s):  
Information Security ◽  
Secret Sharing ◽  
Visual Cryptography ◽  
Color Images ◽  
Secret Sharing Scheme ◽  
Normal Vision ◽  
Visual Secret Sharing ◽  
Pixel Expansion ◽  
Host Image ◽  
Sharing Scheme

Mapping of image-based object textures to ASCII characters can be a new modification towards visual cryptography. Naor and Shamir proposed a new dimension of Information security as visual cryptography which is a secret sharing scheme among N number of participants with pixel expansion. Later on, many researchers extended the visual secret sharing scheme with no expansion of pixel regions in binary and color images. By stacking k shares the secret can be decoded using normal vision. In this paper the authors have proposed a modification towards visual cryptography by converting the message in the form of printable ASCII character-based numerical encoding patterns in a binary host image. The encoding of the message is represented as ASCII numeric and a texture of those numeric are arranged to form a binary host image. Then, N numbers of shares are built up but after stacking all the shares the decoding of the message is achieved by converting ASCII numeric to the secret.

scholarly journals VISUAL CRYPTOGRAPHY FOR COLOR IMAGES

2013 ◽  
pp. 147-149
Author(s):  
ASHWATHIMESANGLA AO
Keyword(s):  
Secret Sharing ◽  
Visual Cryptography ◽  
Color Images ◽  
Secret Sharing Scheme ◽  
Secret Image ◽  
Secret Information ◽  
Host Image ◽  
Sharing Scheme ◽  
Visual Cryptography Scheme

Visual cryptography is a secret sharing scheme for encrypting a secret image, it is a perfectly secure way that allows secret sharing without any cryptographic computation, which is termed as Visual Cryptography Scheme (VCS). In this paper secret image is divided into shares (printed on transparencies), and each share holds some information. At the receiver this shares are merged to obtain the secret information which is revealed without any complex computation. The proposed algorithm is for color host image, divided into three color planes Red, Green, Blue and merged with secret image which is binarized and divided into shares. The decoding requires aligning the result obtained by merging color host image and shares, so as to obtain the secret image.

scholarly journals XOR-ed visual secret sharing scheme with robust and meaningful shadows based on QR codes

2019 ◽  
Vol 79 (9-10) ◽  
pp. 5719-5741 ◽  
Author(s):  
Longdan Tan ◽  
Yuliang Lu ◽  
Xuehu Yan ◽  
Lintao Liu ◽  
Xuan Zhou
Keyword(s):  
Error Correction ◽  
Secret Sharing ◽  
Qr Code ◽  
Quick Response ◽  
Salt And Pepper Noise ◽  
Visual Secret Sharing ◽  
Qr Codes ◽  
Secret Image ◽  
Sharing Scheme ◽  
Salt And Pepper

AbstractQuick response (QR) codes are becoming increasingly popular in various areas of life due to the advantages of the error correction capacity, the ability to be scanned quickly and the capacity to contain meaningful content. The distribution of dark and light modules of a QR code looks random, but the content of a code can be decoded by a standard QR reader. Thus, a QR code is often used in combination with visual secret sharing (VSS) to generate meaningful shadows. There may be some losses in the process of distribution and preservation of the shadows. To recover secret images with high quality, it is necessary to consider the scheme’s robustness. However, few studies examine robustness of VSS combined with QR codes. In this paper, we propose a robust (k, n)-threshold XOR-ed VSS (XVSS) scheme based on a QR code with the error correction ability. Compared with OR-ed VSS (OVSS), XVSS can recover the secret image losslessly, and the amount of computation needed is low. Since the standard QR encoder does not check if the padding codewords are correct during the encoding phase, we replace padding codewords by initial shadows shared from the secret image using XVSS to generate QR code shadows. As a result, the shadows can be decoded normally, and their error correction abilities are preserved. Once all the shadows have been collected, the secret image can be recovered losslessly. More importantly, if some conventional image attacks, including rotation, JPEG compression, Gaussian noise, salt-and-pepper noise, cropping, resizing, and even the addition of camera and screen noises are performed on the shadows, the secret image can still be recovered. The experimental results and comparisons demonstrate the effectiveness of our scheme.

scholarly journals Collusion Attacks in XOR Based RG-VSS

2019 ◽  
Vol 8 (10) ◽  
pp. 2339-2345
Keyword(s):  
Secret Sharing ◽  
Data Security ◽  
Visual Cryptography ◽  
Visual Quality ◽  
Visual Secret Sharing ◽  
Security Issue ◽  
Collusion Attacks ◽  
Secret Image ◽  
The Past

Visual secret sharing (VSS) is a well-known technique from the past few decades for data security. Recently, XOR based VSS has attracted many researchers due to its lossless or good visual quality of reconstructed secret image. Cheating in visual cryptography based VSS was introduced by Horng et. al. in 2006. Cheating occurs when a dishonest participant presents fake share and performs stacking of fake share with honest participants who have genuine share, thereby revealing the fake secret image instead of the original secret image. Cheating occurs when some XOR based VSS are exposed to collusion attacks. Here, in this paper, we have demonstrated and proved that there is a security issue in existing XOR based VSS schemes.

scholarly journals (3, 3) Visual Cryptography for Online Certificate Authentication

2020 ◽  
Vol 9 (6) ◽  
pp. 152-156
Keyword(s):  
Academic Achievement ◽  
Secret Sharing ◽  
Visual Cryptography ◽  
Secret Message ◽  
Secret Sharing Scheme ◽  
Visual Secret Sharing ◽  
Job Interview ◽  
Sharing Scheme ◽  
Visual Cryptography Scheme ◽  
Full Proof

Today organizations face a challenge while recruiting candidates, who provide forged mark sheets in order to get a job. To prevent wrong hiring a detailed and thorough approach is needed to verify the authentication of both the candidate and the marks obtained by him/her. There are so many modern cryptographic protocols available which can be used for authenticating individual’s academic achievement certificates. Visual Cryptography is a simple and secure way to allow the secret sharing of images without any cryptographic computations or the use of encryption or decryption keys. The novelty of the visual secret sharing scheme is in its decryption process where human visual system (HVS) is employed for decryption of secret shares. In this paper we have discussed (3, 3) visual cryptography scheme which can be used to generate shares and distributes them among three parties, i.e. the Job Seeker, Certificate Issuance Authority and the Organization conducting Job interview. Secret message can be decrypted only if all the three shares are available. Every certificate carries a unique number which is encrypted using visual cryptography and without handshaking of all the parties it is impossible to decrypt, thus ensuring full proof authentication.

Sign in / Sign up

Export Citation Format

Share Document