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Author

Nedeljko Cvejic

Other affiliations: University of Oulu
Bio: Nedeljko Cvejic is an academic researcher from University of Bristol. The author has contributed to research in topics: Digital watermarking & Watermark. The author has an hindex of 20, co-authored 49 publications receiving 1754 citations. Previous affiliations of Nedeljko Cvejic include University of Oulu.

Papers
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Journal ArticleDOI
TL;DR: Experimental results have confirmed that the proposed metric outperforms the standard MI metric by correlating better with the subjective quality of fused images.
Abstract: A novel image fusion performance metric using mutual information is proposed. The metric is based on Tsallis entropy, which is a one-parameter generalisation of Shannon entropy. Experimental results have confirmed that the proposed metric outperforms the standard MI metric by correlating better with the subjective quality of fused images.

179 citations

Proceedings ArticleDOI
09 Dec 2002
TL;DR: In this paper, a modification to standard LSB algorithm that is able to embed four bits per sample, thus improving the capacity of data hiding channel by 33% is presented, which makes use of minimum error replacement method for LSB adjustment and modified error diffusion method for decreasing SNR value.
Abstract: Conventionally, a perceptual limit of three bits per sample is imposed to the basic LSB audio steganography method. In this paper, we present a novel modification to standard LSB algorithm that is able to embed four bits per sample, thus improving the capacity of data hiding channel by 33%. The proposed algorithm makes use of minimum error replacement method for LSB adjustment and modified error diffusion method for decreasing SNR value. Objective test showed the algorithm succeeds in this task, while keeping SNR value close to the level of SNR obtained by standard LSB embedding with three bits per sample capacity. Subjective listening test proved that high perceptual transparency is accomplished even if four LSBs of host audio signal are used for data hiding.

169 citations

01 Jan 2004
TL;DR: The main results of this study are the development of novel audio watermarking algorithms, with the state-of-the-art performance and an acceptable increase in computational complexity.
Abstract: Broadband communication networks and multimedia data available in a digital format opened many challenges and opportunities for innovation. Versatile and simple-to-use software and decreasing prices of digital devices have made it possible for consumers from all around the world to create and exchange multimedia data. Broadband Internet connections and near error-free transmission of data facilitate people to distribute large multimedia files and make identical digital copies of them. A perfect reproduction in digital domain have promoted the protection of intellectual ownership and the prevention of unauthorized tampering of multimedia data to become an important technological and research issue. Digital watermarking has been proposed as a new, alternative method to enforce intellectual property rights and protect digital media from tampering. Digital watermarking is defined as imperceptible, robust and secure communication of data related to the host signal, which includes embedding into and extraction from the host signal. The main challenge in digital audio watermarking and steganography is that if the perceptual transparency parameter is fixed, the design of a watermark system cannot obtain high robustness and a high watermark data rate at the same time. In this thesis, we address three research problems on audio watermarking: First, what is the highest watermark bit rate obtainable, under the perceptual transparency constraint, and how to approach the limit? Second, how can the detection performance of a watermarking system be improved using algorithms based on communications models for that system? Third, how can overall robustness to attacks to a watermark system be increased using attack characterization at the embedding side? An approach that combined theoretical consideration and experimental validation, including digital signal processing, psychoacoustic modeling and communications theory, is used in developing algorithms for audio watermarking and steganography. The main results of this study are the development of novel audio watermarking algorithms, with the state-of-the-art performance and an acceptable increase in computational complexity. The algorithms' performance is validated in the presence of the standard watermarking attacks. The main technical solutions include algorithms for embedding high data rate watermarks into the host audio signal, using channel models derived from communications theory for watermark transmission and the detection and modeling of attacks using attack characterization procedure. The thesis also includes a thorough review of the state-of-the-art literature in the digital audio watermarking.

164 citations

Book
07 Aug 2007
TL;DR: A comprehensive compilation of the major theoretical frameworks, research findings, and practical applications of digital audio watermarking, to serve as a vital reference to researchers and practitioners in a variety of disciplines, including engineering, information technology, and digital audio.
Abstract: "Digital audio watermarking has been proposed as a new and alternative method to enforce intellectual property rights and protect digital audio from tampering. Digital Audio Watermarking Techniques and Technologies: Applications and Benchmarks is a comprehensive compilation of the major theoretical frameworks, research findings, and practical applications. With inclusive coverage of the most authoritative research in the area, Digital Audio Watermarking Techniques and Technologies: Applications and Benchmarks will serve as a vital reference to researchers and practitioners in a variety of disciplines, including engineering, information technology, and digital audio. With value to a diverse range of users, this Premier Reference Source suits libraries in numerous settings."

146 citations

Proceedings ArticleDOI
05 Apr 2004
TL;DR: A novel high bit rate LSB audio watermarking method using the proposed two-step algorithm, watermark bits are embedded into higher LSB layers, resulting in increased robustness against noise addition or MPEG compression.
Abstract: We present a novel high bit rate LSB audio watermarking method. The basic idea of the proposed LSB algorithm is watermark embedding that causes minimal embedding distortion of the host audio. Using the proposed two-step algorithm, watermark bits are embedded into higher LSB layers, resulting in increased robustness against noise addition or MPEG compression. Listening tests showed that the perceptual quality of watermarked audio is higher in the case of the proposed method than in the standard LSB method.

140 citations


Cited by
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Book
24 Oct 2001
TL;DR: Digital Watermarking covers the crucial research findings in the field and explains the principles underlying digital watermarking technologies, describes the requirements that have given rise to them, and discusses the diverse ends to which these technologies are being applied.
Abstract: Digital watermarking is a key ingredient to copyright protection. It provides a solution to illegal copying of digital material and has many other useful applications such as broadcast monitoring and the recording of electronic transactions. Now, for the first time, there is a book that focuses exclusively on this exciting technology. Digital Watermarking covers the crucial research findings in the field: it explains the principles underlying digital watermarking technologies, describes the requirements that have given rise to them, and discusses the diverse ends to which these technologies are being applied. As a result, additional groundwork is laid for future developments in this field, helping the reader understand and anticipate new approaches and applications.

2,849 citations

01 Apr 1997
TL;DR: The objective of this paper is to give a comprehensive introduction to applied cryptography with an engineer or computer scientist in mind on the knowledge needed to create practical systems which supports integrity, confidentiality, or authenticity.
Abstract: The objective of this paper is to give a comprehensive introduction to applied cryptography with an engineer or computer scientist in mind. The emphasis is on the knowledge needed to create practical systems which supports integrity, confidentiality, or authenticity. Topics covered includes an introduction to the concepts in cryptography, attacks against cryptographic systems, key use and handling, random bit generation, encryption modes, and message authentication codes. Recommendations on algorithms and further reading is given in the end of the paper. This paper should make the reader able to build, understand and evaluate system descriptions and designs based on the cryptographic components described in the paper.

2,188 citations

Journal ArticleDOI
TL;DR: Experimental results demonstrate that the proposed method can obtain state-of-the-art performance for fusion of multispectral, multifocus, multimodal, and multiexposure images.
Abstract: A fast and effective image fusion method is proposed for creating a highly informative fused image through merging multiple images. The proposed method is based on a two-scale decomposition of an image into a base layer containing large scale variations in intensity, and a detail layer capturing small scale details. A novel guided filtering-based weighted average technique is proposed to make full use of spatial consistency for fusion of the base and detail layers. Experimental results demonstrate that the proposed method can obtain state-of-the-art performance for fusion of multispectral, multifocus, multimodal, and multiexposure images.

1,300 citations

Journal ArticleDOI
TL;DR: It is concluded that although various image fusion methods have been proposed, there still exist several future directions in different image fusion applications and the researches in the image fusion field are still expected to significantly grow in the coming years.

871 citations

Journal ArticleDOI
Jiayi Ma1, Yong Ma1, Chang Li1
TL;DR: This survey comprehensively survey the existing methods and applications for the fusion of infrared and visible images, which can serve as a reference for researchers inrared and visible image fusion and related fields.

849 citations