1. Digital Fingerprinting for Multimedia Content Protection Avinash L. Varna Advisor: Prof. Min Wu Department of Electrical and Computer Engineering University of Maryland, College Park

2. Motivation Alice w1 w2 Embed Fingerprints Bob w3 Carl Alice,Bob, … Detect Fingerprints Identify Content ShutterIsland Internet Alice,Bob, … Alice Shutter Island Bob Carl Embedded Fingerprints Content Fingerprints Collusion-resistant Fingerprint Design for Compressed Multimedia Analysis of Fingerprints for Content Identification

3. Fingerprinting Compressed Multimedia Set Top Box Decrypt Decompress Pirated Copy Compressed video Cable TV distribution system Embed Fingerprint Collude Challenges: Discrete nature of host makes embedded fingerprint vulnerable to multi-user collusion attack Traditional fingerprinting: averaging ~10 copies sufficient to remove fingerprints Fingerprint embedding should not significantly increase file size

5. Anti-Collusion Dither Add a dither signal before embedding to make the host appear more continuous Collusion resistance increases to ~30 colluders (from ~7) Theoretical Analysis: More users can be accommodated under given attack Difficult for attacker to estimate host accurately Derived expressions for Probability of detection PD Simulations using images: Preserves visual quality File size does not increase significantly A. L. Varna, S. He, A. Swaminathan, and M. Wu, "Fingerprinting Compressed Multimedia Signals", IEEE Transactions on Information Forensics and Security, Sep. 2009, pp 330-345.

6. Multimedia Content Identification Content Filtering Metadata Services From Verizon Shazam for iPhone Developed framework for modeling and understanding Analyze the mapping from video to features to bits:how is processing on video translated to changes in fingerprint bits? Model performance at bit string level Quantization & Encoding Feature Extraction Matching Video

8. Theoretical Analysis and Results Simple model : i.i.d. equiprobable fingerprint bits and noise alters each bit independently with probability p Derived guideline for choosing fingerprint length Game-theoretic analysis to derive optimal strategies for attacker and detector Markov Random Field model to capture correlations Understand influence of correlation on detection Cannot estimate rare-event probability accurately using traditional Markov Chain Monte-Carlo (MCMC) simulations Use statistical physics inspired approachto compute probabilities Noise Original Fingerprint A. L. Varna and M. Wu, "Theoretical Modeling and Analysis of Content Fingerprinting", submitted to the IEEE Transactions on Information Forensics and Security, Dec. 2009.

9. Contributions of the Dissertation Multimedia Content Protection Deterrence & Tracing Identification & Filtering Collusion-resistant Fingerprints Content Fingerprintsfor Identification

10. Selected Publications Journal Papers A. L. Varna, S. He, A. Swaminathan, and M. Wu, "Fingerprinting Compressed Multimedia Signals", IEEE Transactions on Information Forensics and Security, Sep. 2009, pp 330-345. A. L. Varna and M. Wu, "Theoretical Modeling and Analysis of Content Fingerprinting", submitted to the IEEE Transactions on Information Forensics and Security, Dec. 2009. Wenjun Lu, A.L. Varna, AshwinSwaminathan, and Min Wu, "Privacy Preserving Multimedia Retrieval", submitted to IEEE Transactions on Information Forensics and Security, Oct. 2009, under revision. A. L. Varna and M. Wu, “Game-theoretic Analysis of Content Fingerprinting”, under preparation. Selected Conference Papers A. L. Varna, Shan He, AshwinSwaminathan, Min Wu, Haiming Lu, and Zengxiang Lu, "Collusion-Resistant Fingerprinting for Compressed Multimedia Signals", IEEE International Conference on Acoustics, Speech and Signal Processing, vol. 2, pp. 165 - 168, Apr. 2007. A. L. Varna, AshwinSwaminathan, and Min Wu, "A Decision Theoretic Framework for Analyzing Hash-based Content Identification Systems", ACM Digital Rights Management Workshop, pp. 67-76 Oct. 2008. A. L. Varna and Min Wu, "Modeling and Analysis of Content Identification", IEEE International Conference on Multimedia and Expo, pp. 1529-1531, Jun. 2009. A. L. Varna, Wei-Hong Chuang, and Min Wu, "A Framework for Theoretical Analysis of Content Fingerprinting", SPIE and IS&T Media Forensics and Security, Jan. 2010.

11. Contributions of the Dissertation Collusion-resistant fingerprints for compressed multimedia Evaluated performance of Gaussian based sequences Introduced Anti-Collusion Dither that can approximately triplethe collusion resistance Analyzed performance of techniques from different viewpoints Analysis of multimedia content identification Developed a theoretical framework for analyzing content identification schemes Proposed models for binary fingerprints and derived fundamental bounds on performance Performed game-theoretic analysis of interaction between the system designer and attacker