Anthony Tung Shuen Ho

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A novel H.264/AVC watermarking method is proposed in this paper. By embedding the robust watermark into DCT domain and the fragile watermark into motion vectors respectively, the proposed method can jointly achieve both copyright protection and authentication. Our scheme outperforms other video watermarking schemes on higher watermarking capacity especially(More)
A robust video watermarking scheme of the state-of-the-art video coding standard H.264/AVC is proposed in this brief. 2-D 8-bit watermarks such as detailed company trademarks or logos can be used as inconvertible watermark for copyright protection. A grayscale watermark pattern is first modified to accommodate the H.264/AVC computational constraints, and(More)
In this paper, a new fragile watermarking method for digital image authentication is proposed based on the zero locations of the -transform. The -transform domain is a new transform space for fragile watermark embedding. Our watermarking method is designed by exploiting the sensitivity of the positions of the zeroes of the -transform around the unit circle(More)
This paper presents a semi-fragile watermarking method for the automatic authentication and restoration of the content of digital images. Semi-fragile watermarks are embedded into the original image, which reflect local malicious tampering on the image. When tampered blocks are detected, the restoration problem is formulated as an irregular sampling(More)
Rendering a face recognition system robust is vital in order to safeguard it against spoof attacks carried out using printed pictures of a victim (also known as print attack) or a replayed video of the person (replay attack). A key property in distinguishing a live, valid access from printed media or replayed videos is by exploiting the information dynamics(More)
In this paper, a robust and efficient digital image watermarking algorithm using the fast Hadamard transform (FHT) is proposed for the copyright protection of digital images. This algorithm can embed or hide an entire image or pattern as a watermark such as a company’s logo or trademark directly into the original image. The performance of the proposed(More)
This paper proposed a novel and efficient scheme to authenticate the H.264/AVC video. The scheme makes an accurate usage of the tree-structured motion compensation, motion estimation and Lagrangian optimization of the standard. Authentication information is embedded strictly based on the best mode decision strategy in the sense that if undergone any spatial(More)
The use of a suitable perceptual model is necessary to minimize the visual distortion in the marked images, because minor modification to the pixels can be perceptible since the pixels are either black or white. In this paper, a new perceptual model is proposed for binary images that is useful for data hiding applications. In our model, the distortion that(More)
In this paper we propose a multi-set modulation technique to increase the hiding capacity within a binary document image. As part of this technique we propose an Automatic Threshold Calculation and Threshold Buffering, Shifted Space Distribution and Letter Space Compensation technique. The Automatic Threshold Calculation is used to distinguish word spaces(More)
In the past few years, semi-fragile watermarking has become increasingly important to verify the content of images and localise the tampered areas, while tolerating some non-malicious manipulations. Moreover, some researchers proposed self-restoration schemes to recover the tampered area in semi-fragile watermarking schemes. In this paper, we propose a(More)