This paper presents a multiple watermarking scheme for color images by using the concept of visual cryptography, wavelet tree, integer wavelet transform, and YCbCr color model. Experiment results show that all owners will have dual watermark authentication embedded in a protected color image, and the number of ownerships can be increased without re-computing. Applying the proposed four points distinguishing law, the owneri¦s dual watermarks can be extracted more imperceptibly.

A Multiple Watermarking Scheme for Color Images

Received: 13 November 2020 Accepted: 29 January 2021 The current era is mainly focused on secured data transmission and every organization takes preventive measures to protect network’s private data. Among different techniques visual cryptography is a prominent one that that encrypts the visual information and decrypts secret using mechanical operations without any computation, but each share need pixel expansion. In the current work, we propose an Image encryption technique using (n, n) Visual cryptography based on simple operations without pixel expansion. The proposed novel technique gives an image encryption using visual cryptography based on Least significant bit (LSB) technique in spatial domain and parity mechanism using ExclusiveOR(XOR) operation. developed for encrypting grey scale image. Image encryption and decryption uses simple Boolean operations. The technique provides better quality of shares and recovers without any loss.

/pdf/a-novel-image-encryption-using-parity-based-visual-3lf2aiyvtw.pdf

A Novel Image Encryption Using Parity Based Visual Cryptography

In practical video storage and distribution systems, video sequences are stored and transmitted in a compressed format. During compression, the video frame is transformed from the spatial domain into frequency domain. Therefore, video content authentication methods need to be robust to lossy compression. This paper proposes a novel semi-fragile watermarking video content authentication based on a hybrid feature, consisting of gray threshold and relative total variation edge feature. The watermark is encrypted and embedded into the principal diagonal of 8×8 DCT coefficients. At the receiver side, when a part of the watermarked video is tampered, the proposed approach can locate these tampered areas. The experiment demonstrates the proposed method can distinguish malicious attacks from the legitimate common alterations, such as H.264 lossy compression, Gaussian noise and Gaussian filtering. It has outstanding capability to robust to H.264 compression and to detect malicious attacks. The experiment shows that the proposed method has higher recall and precision than the current approaches.

/pdf/semi-fragile-watermarking-for-video-content-authentication-4kujz8s6bm.pdf

Semi-fragile Watermarking for Video Content Authentication Based on Hybrid Feature

A multiple watermarking scheme for gray-level images by using visual cryptography, modified histogram, integer wavelet transform, and the wavelet tree is presented. The process rearranges the share im- age and embeds it in the coefficients of the corresponding IWT middle frequencies, and the owner keeps an- other share image as the key. Under this scheme, all owners will have dual watermark authentication, and through this method, the number of ownerships can be increased. The goal of the proposed scheme for multi- ple watermarking is to satisfy more requirements of the watermarking characteristics. From security point of view, without the personal key share images, even if the hidden share images were retrieved to obtain the original share image, the watermark information remains unavailable. Applying the proposed four points dis- tinguishing law and bitwise right shift operation, and the share image blocks deciphering rule, the owner's dual watermarks can be extracted to verify the ownership.

https://csroc.org.tw/journal/E_Published%20Vol_22_No_1.files/3abs.pdf

Hsim Wei Huang

Papers

A Multiple Watermarking Scheme for Gray-Level Images using Visual Cryptography and Integer Wavelet Transform