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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Digital video watermarking techniques for secure multimedia creation and delivery.

January 2004 (has links)
Chan Pik-Wah. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 111-130). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iv / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Research Objective --- p.3 / Chapter 1.3 --- Contributions --- p.4 / Chapter 1.4 --- The Structure of this Thesis --- p.6 / Chapter 2 --- Literature Review --- p.7 / Chapter 2.1 --- Security in Multimedia Communications --- p.8 / Chapter 2.2 --- Cryptography --- p.11 / Chapter 2.3 --- Digital Watermarking --- p.14 / Chapter 2.4 --- Essential Ingredients for Video Watermarking --- p.16 / Chapter 2.4.1 --- Fidelity --- p.16 / Chapter 2.4.2 --- Robustness --- p.17 / Chapter 2.4.3 --- Use of Keys --- p.19 / Chapter 2.4.4 --- Blind Detection --- p.20 / Chapter 2.4.5 --- Capacity and Speed --- p.20 / Chapter 2.4.6 --- Statistical Imperceptibility --- p.21 / Chapter 2.4.7 --- Low Error Probability --- p.21 / Chapter 2.4.8 --- Real-time Detector Complexity --- p.21 / Chapter 2.5 --- Review on Video Watermarking Techniques --- p.22 / Chapter 2.5.1 --- Video Watermarking --- p.25 / Chapter 2.5.2 --- Spatial Domain Watermarks --- p.26 / Chapter 2.5.3 --- Frequency Domain Watermarks --- p.30 / Chapter 2.5.4 --- Watermarks Based on MPEG Coding Struc- tures --- p.35 / Chapter 2.6 --- Comparison between Different Watermarking Schemes --- p.38 / Chapter 3 --- Novel Watermarking Schemes --- p.42 / Chapter 3.1 --- A Scene-based Video Watermarking Scheme --- p.42 / Chapter 3.1.1 --- Watermark Preprocess --- p.44 / Chapter 3.1.2 --- Video Preprocess --- p.46 / Chapter 3.1.3 --- Watermark Embedding --- p.48 / Chapter 3.1.4 --- Watermark Detection --- p.50 / Chapter 3.2 --- Theoretical Analysis --- p.52 / Chapter 3.2.1 --- Performance --- p.52 / Chapter 3.2.2 --- Capacity --- p.56 / Chapter 3.3 --- A Hybrid Watermarking Scheme --- p.60 / Chapter 3.3.1 --- Visual-audio Hybrid Watermarking --- p.61 / Chapter 3.3.2 --- Hybrid Approach with Different Water- marking Schemes --- p.69 / Chapter 3.4 --- A Genetic Algorithm-based Video Watermarking Scheme --- p.73 / Chapter 3.4.1 --- Watermarking Scheme --- p.75 / Chapter 3.4.2 --- Problem Modelling --- p.76 / Chapter 3.4.3 --- Chromosome Encoding --- p.79 / Chapter 3.4.4 --- Genetic Operators --- p.80 / Chapter 4 --- Experimental Results --- p.85 / Chapter 4.1 --- Test on Robustness --- p.85 / Chapter 4.1.1 --- Experiment with Frame Dropping --- p.87 / Chapter 4.1.2 --- Experiment with Frame Averaging and Sta- tistical Analysis --- p.89 / Chapter 4.1.3 --- Experiment with Lossy Compression --- p.90 / Chapter 4.1.4 --- Test of Robustness with StirMark 4.0 --- p.92 / Chapter 4.1.5 --- Overall Comparison --- p.98 / Chapter 4.2 --- Test on Fidelity --- p.100 / Chapter 4.2.1 --- Parameter(s) Setting --- p.101 / Chapter 4.2.2 --- Evaluate with PSNR --- p.101 / Chapter 4.2.3 --- Evaluate with MAD --- p.102 / Chapter 4.3 --- Other Features of the Scheme --- p.105 / Chapter 4.4 --- Conclusion --- p.106 / Chapter 5 --- Conclusion --- p.108 / Bibliography --- p.110
2

Content identification using video tomography

Unknown Date (has links)
Video identification or copy detection is a challenging problem and is becoming increasingly important with the popularity of online video services. The problem addressed in this thesis is the identification of a given video clip in a given set of videos. For a given query video, the system returns all the instance of the video in the data set. This identification system uses video signatures based on video tomography. A robust and low complexity video signature is designed and implemented. The nature of the signature makes it independent to the most commonly video transformations. The signatures are generated for video shots and not individual frames, resulting in a compact signature of 64 bytes per video shot. The signatures are matched using simple Euclidean distance metric. The results show that videos can be identified with 100% recall and over 93% precision. The experiments included several transformations on videos. / by Gustavo A. Leon. / Thesis (M.S.C.S.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2008. Mode of access: World Wide Web.
3

The inexact Newton-like method for inverse eigenvalue problem and a DCT based watermarking scheme for copyright protection of images.

January 2002 (has links)
by Hau-Leung Chung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 41-42). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.5 / Chapter 1.1 --- Paper I --- p.5 / Chapter 1.2 --- Paper II --- p.6 / Chapter 2 --- The Inexact Newton-Like Method for Inverse Eigen- value Problem --- p.8 / Chapter 2.1 --- Introduction --- p.8 / Chapter 2.2 --- The Newton-Like Method --- p.9 / Chapter 2.3 --- The Inexact Newton-Like Method --- p.11 / Chapter 2.4 --- Convergence Analysis --- p.14 / Chapter 2.5 --- Numerical Experiments --- p.22 / Chapter 3 --- A DCT Based Watermarking Scheme for Copyright Protection of Images --- p.26 / Chapter 3.1 --- Introduction --- p.26 / Chapter 3.2 --- Preliminary --- p.28 / Chapter 3.2.1 --- Gray-level image --- p.28 / Chapter 3.2.2 --- Color image --- p.29 / Chapter 3.2.3 --- The Discrete Cosine transform --- p.30 / Chapter 3.3 --- Watermarking Approaches --- p.31 / Chapter 3.3.1 --- Insertion procedures --- p.31 / Chapter 3.3.2 --- Retrieval procedures --- p.33 / Chapter 3.4 --- Experimental results --- p.34 / Chapter 3.5 --- Other Applications --- p.38 / Chapter 3.5.1 --- Data Hiding --- p.38 / Chapter 3.5.2 --- Authentication --- p.39 / Chapter 3.5.3 --- Fingerprinting --- p.39 / Chapter 3.5.4 --- Copy Control --- p.39 / Chapter 3.6 --- Conclusion --- p.40 / Bibliography --- p.41
4

Software and Hardware-In-The-Loop Modeling of an Audio Watermarking Algorithm

Zarate Orozco, Ismael 12 1900 (has links)
Due to the accelerated growth in digital music distribution, it becomes easy to modify, intercept, and distribute material illegally. To overcome the urgent need for copyright protection against piracy, several audio watermarking schemes have been proposed and implemented. These digital audio watermarking schemes have the purpose of embedding inaudible information within the host file to cover copyright and authentication issues. This thesis proposes an audio watermarking model using MATLAB® and Simulink® software for 1K and 2K fast Fourier transform (FFT) lengths. The watermark insertion process is performed in the frequency domain to guarantee the imperceptibility of the watermark to the human auditory system. Additionally, the proposed audio watermarking model was implemented in a Cyclone® II FPGA device from Altera® using the Altera® DSP Builder tool and MATLAB/Simulink® software. To evaluate the performance of the proposed audio watermarking scheme, effectiveness and fidelity performance tests were conducted for the proposed software and hardware-in-the-loop based audio watermarking model.
5

Robust digital watermarking of multimedia objects

Gupta, Gaurav January 2008 (has links)
Thesis (PhD)--Macquarie University, Division of Information and Communication Sciences, Department of Computing, 2008. / Bibliography: p. 144-153. / Introduction -- Background -- Overview of watermarking -- Natural language watermarking -- Software watermarking -- Semi-blind and reversible database watermarking -- Blind and reversible database watermarking -- Conclusion and future research -- Bibliography. / Digital watermarking has generated significant research and commercial interest in the past decade. The primary factors contributing to this surge are widespread use of the Internet with improved bandwidth and speed, regional copyright loopholes in terms of legislation; and seamless distribution of multimedia content due to peer-to-peer file-sharing applications. -- Digital watermarking addresses the issue of establishing ownership over mul-timedia content through embedding a watermark inside the object. Ideally, this watermark should be detectable and/or extractable, survive attacks such as digital reproduction and content-specific manipulations such as re-sizing in the case of images, and be invisible to the end-user so that the quality of the content is not degraded significantly. During detection or extraction, the only requirements should be the secret key and the watermarked multimedia object, and not the original un-marked object or the watermark inserted. Watermarking scheme that facilitate this requirement are categorized as blind. In recent times, reversibility of watermark has also become an important criterion. This is due to the fact that reversible watermarking schemes can provided security against secondary watermarking attacks by using backtracking algorithms to identify the rightful owner. A watermarking scheme is said to be reversible if the original unmarked object can be regenerated from the watermarked copy and the secret key. / This research covers three multimedia content types: natural language documents, software, and databases; and discusses the current watermarking scenario, challenges, and our contribution to the field. We have designed and implemented a natural language watermarking scheme that uses the redundancies in natural languages. As a result, it is robust against general attacks against text watermarks. It offers additional strength to the scheme by localizing the attack to the modified section and using error correction codes to detect the watermark. Our first contribution in software watermarking is identification and exploitation of weaknesses in branch-based software watermarking scheme proposed in [71] and the software watermarking algorithm we present is an improvised version of the existing watermarking schemes from [71]. Our scheme survives automated debugging attacks against which the current schemes are vulnerable, and is also secure against other software-specific attacks. We have proposed two database watermarking schemes that are both reversible and therefore resilient against secondary watermarking attacks. The first of these database watermarking schemes is semi-blind and requires the bits modified during the insertion algorithm to detect the watermark. The second scheme is an upgraded version that is blind and therefore does not require anything except a secret key and the watermarked relation. The watermark has a 89% probability of survival even when almost half of the data is manipulated. The watermarked data in this case is extremely useful from the users' perspective, since query results are preserved (i.e., the watermarked data gives the same results for a query as the nmarked data). -- The watermarking models we have proposed provide greater security against sophisticated attacks in different domains while providing sufficient watermark-carrying capacity at the same time. The false-positives are extremely low in all the models, thereby making accidental detection of watermark in a random object almost negligible. Reversibility has been facilitated in the later watermarking algorithms and is a solution to the secondary watermarking attacks. We shall address reversibility as a key issue in our future research, along with robustness, low false-positives and high capacity. / Mode of access: World Wide Web. / xxiv, 156 p. ill. (some col.)

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