Joint Colloquium Distinguished Lecture Series

Cybercasing the Joint: On the Privacy Implications of Multimedia Retrieval

Gerald Friedland

Wednesday, September 5, 2012
306 Soda Hall (HP Auditorium)
4:00 - 5:00 pm

Gerald Friedland
Senior research scientist, International Computer Science Insititute (ICSI)

Downloadable pdf


Abstract: In this talk, I present recent case studies that highlight the potential for multimedia retrieval of online (social network) data to support real-world attacks. Multimedia Retrieval, i.e., the task of matching and comparing multimedia content across databases, has rapidly emerged as a field with highly useful applications in many different domains. Researchers from different areas in signal processing and computer science (including the presenter) have invested significant effort into the development of convenient and efficient retrieval mechanisms. While retrieval speed, flexibility, and accuracy are still research problems, this talk will demonstrate that they are not the only ones.

This talk aims to raise awareness for a rapidly emerging privacy threat that we termed "cybercasing": leveraging information available online to mount real-world attacks. Based on the initial example of geo-tagging, I will show that while users typically realize that sharing information, e.g., on social networks, has some implications for their privacy, many users 1) are unaware of the full scope of the threat they face when doing so, and 2) often do not even realize when they publish such information. The threat is elevated by recent developments that make systematic search for information (either posted by humans or by sensors) and inference from multiple sources easier than ever before. However, even with relatively high error rates, multimedia retrieval techniques can be used effectively for different real-world attacks by using "lop-sided" tuning; for example by favoring low false alarm rates over high hit rates when scanning for potential victims to attack.

This talk presents a set of scenarios demonstrating how easy it is to correlate data [1,2,3,4] with corresponding publicly available information for compromising a victim's privacy.

[1] G. Friedland, O. Vinyals, T. Darrell: "Multimodal Location Estimation", Proceedings of ACM Multimedia 2010, pp. 1245-1251, Florence, Italy, October 2010.
[2] H. Lei, J. Choi, A. Janin, and G. Friedland: "Persona Linking: Matching Uploaders of Videos Accross Accounts", IEEE International Conference on Acoustic, Speech, and Signal Processing (ICASSP), Prague, May 2011.
[3] G. Friedland, R. Sommer: "Cybercasing the Joint: On the Privacy Implications of Geotagging", Usenix HotSec 2010 at the Usenix Security Conference, Washington DC, August 2010.
[4] Gerald Friedland, Gregor Maier, Robin Sommer, Nicholas Weaver: Sherlock Holmes’s Evil Twin: On The Impact of Global Inference for Online Privacy, New Security Paradigms Workshop, Marin County, CA, 2011.


Dr. Gerald Friedland is a senior research scientist at the International Computer Science Institute, a private research lab affiliated with the University of California, Berkeley, where he leads a multimedia group, mostly focussing on acoustic techniques such as speaker diarization and acoustic event detection. He is currently PI on an IARPA-funded project on video concept detection, a PI on a DARPA project on multimodal grounded learning for robots, a PI on an NSF project on the human accuracy of location estimation, a PI on an industry-funded project on video duplicate detection using acoustic methods, and co-PI on an NSF project on the privacy implications of global inference.

He is also a member of the Executive Advisory Board of UC Berkeley’s Opencast project. Until 2009 he was site manager in the EU-funded project AMIDA and the Swiss-funded IM2 project, both of which explored multimedia meeting analysis. He was program co-chair of the IEEE International Symposium on Multimedia 2008 and 2009. He co-founded the IEEE International Conference on Semantic Computing and is a proud founder and program director of the IEEE International Summer School on Semantic Computing at UC Berkeley. He is also a program co-chiar of ICME 2012 and a program committee member of ACM Multimedia 2009, senior TPC member 2010, and Grand Challenge chair 2011.

Prior to this, he co-authored SIOX (Simple Interactive Object Extraction), which has become the open-source standard algorithm for interactive image cut and paste used in GIMP, Blender, and Inkscape. He was also one of the main developers of the E-Chalk software, a system to replace the traditional chalkboard with modern electronic means. As a result he is involved with the Berkeley Opencast lecture webcasting project and was a Google Summer of Code Mentor for the GNU Image Manipulation Program (GIMP) in 2009.

Dr. Friedland has published more than 100 peer-reviewed articles in conferences, journals, and books and is currently authoring a new textbook on multimedia computing together with Dr. Ramesh Jain. He is associate editor for ACM Transactions on Multimedia Computing, Communications, and Applications and  regulary reviews for IEEE Transactions on Acoustics, Speech, and Language Processing, IEEE Transaction on Multimedia, IEEE Multimedia, Springer’s Machine Vision and Application, and other journals. He is the recipient of several research and industry recognitions, among them the European Academic Software Award and the Multimedia Entrepreneur Award by the German Federal Department of Economics. Most recently, he lead the team that won the ACM Multimedia Grand Challenge in 2009. Dr. Friedland received his doctorate (summa cum laude) and master’s degree in computer science from Freie Universitaet Berlin, Germany, in 2002 and 2006, respectively.

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