Anthony Tung Shuen Ho

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—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)
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 out-performs other video watermarking schemes on higher wa-termarking capacity(More)
Digital image content authentication addresses the problem of detecting any illegitimate modification on the content of images. To cope with this problem, a novel semifragile watermarking scheme using the pinned sine transform (PST) is presented in this paper. The watermarking system can localize the portions of a watermarked image that have been tampered(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)
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)
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)
Steganalysis, the method to detect steganographically embedded hidden messages in digital data, has received an increasing interest in recent years. Although significant research efforts have been devoted to develop steganaly-sis techniques for still-images, video steganalysis remains largely an explored area. In this paper, we investigate how the temporal(More)
In this paper, a fragile watermarking method for authentication of biomedical images is proposed in the z-transform domain based on the zero locations. The z­ transform is a convenient yet invaluable tool for representing, analyzing and designing discrete-time signals and system. Our watermarking method is designed by exploiting the sensitivity of the(More)