Digital audio watermarking for broadcast monitoring and content identification

Copyright legislation was prompted exactly 300 years ago by a desire to protect authors against exploitation of their work by others. With regard to modern content owners, Digital Rights Management (DRM) issues have become very important since the advent of the Internet. Piracy, or illegal copying, costs content owners billions of dollars every year. DRM is just one tool that can assist content owners in exercising their rights. Two categories of DRM technologies have evolved in digital signal processing recently, namely digital fingerprinting and digital watermarking. One area of Copyright that is consistently overlooked in DRM developments is 'Public Performance'. The research described in this thesis analysed the administration of public performance rights within the music industry in general, with specific focus on the collective rights and broadcasting sectors in Ireland. Limitations in the administration of artists' rights were identified. The impact of these limitations on the careers of developing artists was evaluated. A digital audio watermarking scheme is proposed that would meet the requirements of both the broadcast and collective rights sectors. The goal of the scheme is to embed a standard identifier within an audio signal via modification of its spectral properties in such a way that it would be robust and perceptually transparent. Modification of the audio signal spectrum was attempted in a variety of ways. A method based on a super-resolution frequency identification technique was found to be most effective. The watermarking scheme was evaluated for robustness and found to be extremely effective in recovering embedded watermarks in music signals using a semi-blind decoding process. The final digital audio watermarking algorithm proposed facilitates the development of other applications in the domain of broadcast monitoring for the purposes of equitable royalty distribution along with additional applications and extension to other domains

Digital video watermarking techniques for secure multimedia creation and delivery.

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

Digital Watermarking for Verification of Perception-based Integrity of Audio Data

In certain application fields digital audio recordings contain sensitive content. Examples are historical archival material in public archives that preserve our cultural heritage, or digital evidence in the context of law enforcement and civil proceedings. Because of the powerful capabilities of modern editing tools for multimedia such material is vulnerable to doctoring of the content and forgery of its origin with malicious intent. Also inadvertent data modification and mistaken origin can be caused by human error. Hence, the credibility and provenience in terms of an unadulterated and genuine state of such audio content and the confidence about its origin are critical factors. To address this issue, this PhD thesis proposes a mechanism for verifying the integrity and authenticity of digital sound recordings. It is designed and implemented to be insensitive to common post-processing operations of the audio data that influence the subjective acoustic perception only marginally (if at all). Examples of such operations include lossy compression that maintains a high sound quality of the audio media, or lossless format conversions. It is the objective to avoid de facto false alarms that would be expectedly observable in standard crypto-based authentication protocols in the presence of these legitimate post-processing. For achieving this, a feasible combination of the techniques of digital watermarking and audio-specific hashing is investigated. At first, a suitable secret-key dependent audio hashing algorithm is developed. It incorporates and enhances so-called audio fingerprinting technology from the state of the art in contentbased audio identification. The presented algorithm (denoted as ”rMAC” message authentication code) allows ”perception-based” verification of integrity. This means classifying integrity breaches as such not before they become audible. As another objective, this rMAC is embedded and stored silently inside the audio media by means of audio watermarking technology. This approach allows maintaining the authentication code across the above-mentioned admissible post-processing operations and making it available for integrity verification at a later date. For this, an existent secret-key ependent audio watermarking algorithm is used and enhanced in this thesis work. To some extent, the dependency of the rMAC and of the watermarking processing from a secret key also allows authenticating the origin of a protected audio. To elaborate on this security aspect, this work also estimates the brute-force efforts of an adversary attacking this combined rMAC-watermarking approach. The experimental results show that the proposed method provides a good distinction and classification performance of authentic versus doctored audio content. It also allows the temporal localization of audible data modification within a protected audio file. The experimental evaluation finally provides recommendations about technical configuration settings of the combined watermarking-hashing approach. Beyond the main topic of perception-based data integrity and data authenticity for audio, this PhD work provides new general findings in the fields of audio fingerprinting and digital watermarking. The main contributions of this PhD were published and presented mainly at conferences about multimedia security. These publications were cited by a number of other authors and hence had some impact on their works

Landscapes of the unconscious mind : a dialectic of self and memory on a post-colonial, South African landscape in the hand-animated, charcoal-medium films of William Kentridge

This dissertation focuses on the animated, charcoal, hand-drawn films of William Kentridge‟s Drawings for Projection series (1989—2003). At the beginning of this study, Kentridge‟s films are positioned as a dialectic of self and memory as embodied in a post-colonial South African setting. The series itself was selected as being representative of his artistic oeuvre. They are a closed-ended narrative, using a ground-breaking animation technique, created by the artist himself (Christov-Bakargiev 1998; Godby 1982). They were made by Kentridge during a specific South African cultural and historical period: beginning with Johannesburg, 2nd Greatest City after Paris, made in 1989 at the height of apartheid; through to Tide Table, made in 2003 at the beginning of post post-apartheid South Africa. The hypothesis presented is that Kentridge‟s films have memory as their main theme. Memory itself takes different forms, and the discourse of memory deals with, for instance: memorialisation; repressed memories; traumatic memories; the unconscious and memories; and “postmemory”. How he depicts memories of his own and those of others is at the centre of this research. Using qualitative research methodology, with contextualisation (socio-historical and cultural) and comparative studies (apartheid and the Holocaust; different artistic representations of memory, for example Pascal Croci and William Kentridge; and Anselm Kiefer and William Kentridge) being part of the research design, this thesis has sought to substantiate this hypothesis. Further substantiation and clarification has been expounded by referencing seminal works in the field, such as those of Sigmund Freud (1899: “screen memories”; 1917: trauerarbeit); Roland Barthes (1981: the punctum / spacio-temporal continuum); Pierre Nora (1989: “lieux de mémoiré” / “sites of memory”); Henri Raczymow (1994: “memoire trouée” / “memory shot through with holes”); Richard Terdiman (1993: poesis); Marianne Hirsch (1997: “postmemory”); and Hayden White (1996: historical metafiction); among others. There have already been numerous references to how William Kentridge has depicted the ephemeral nature of memory / memories (Boris 2001; Cameron, Christov-Bakargiev and Coetzee, 1999; Christov-Bakargiev 1998; Sitas 2001). However an in-depth, hermeneutic, comparative analysis has not yet been undertaken. This study is therefore significant in that it explicates William Kentridge‟s works, making the following contributions: to the scholarship on Kentridge‟s work; to a South African perspective to the growing field of trauma studies; and to the apartheid and post-apartheid reflections on re-remembering and forgetting, memorialisation, forgiveness and guilt. Through socio-cultural and historical comparisons as well as artistic contrasts, the films themselves are acknowledged as an important source of reference of South African society. They are a documentation of life lived during apartheid and post-apartheid South Africa.Department of Communication ScienceD. Litt. et Phil

Novel muteness based embedding technique for robust and imperceptible audio watermarking

In recent years digital watermarking of audio signals has gained importance. Digital watermarking represents an efficient state-of-the-art technology for preventing intellectual property rights violations of audio signals by ensuring data integrity and data origin authenticity since it makes it possible to identify the source, author, creator, owner, distributor or authorized recordings. This thesis focuses on the study and implementation of an improved version of the muteness-based watermarking algorithm. The new algorithm has enhanced features when compared to the muteness based technique as repetition codes and secret keys are part of the embedding algorithm. The proposed algorithm is a time domain algorithm as the watermark is added in the muteness period of the original signal. This type of embedding minimizes the audibility of the watermark signal while maximizing robustness to attacks. The added watermark carries information pertaining to copyright protection. A better performance in terms of recovery rate is achieved by using a low rate repetition code as part of the encoder design. A detailed analysis of the watermarking algorithm is done by testing the algorithm for various single and multiple attacks and comparing them with the existing algorithms. It is found that the watermark is robust and imperceptible --Abstract, page iii