The 2012 Social Event Detection Task
The Social Event Detection (SED) task of MediaEval 2012 required participants to discover social events and detect related media items.

The data for the SED 2012 task has been made available by the task organizers here:
By social events, we mean that the events are planned by people, attended by people and that the media illustrating the events are captured by people. A social event of interest can be specified in terms of event-related metadata (e.g., location, time, venue, and performers), example tags or other social information, example media items (images), or a combination of the above. For example, an event of interest or a set of such events could be specified as "football games that took place in Rome in January 2012". Three challenges, each being about finding the events and the related media items that fit to a different event description such as the above, will be specified as part of the 2012 SED task. The systems that will be built by the task participants for addressing the defined challenges can use any combination of the available information (e.g., metadata, visual content, etc.) for detecting media items related to these interesting happenings within a pool of test data (images accompanied by, possibly incomplete, tags, time and location metadata, social information etc.) that will be provided to them by the task organizers.

Target group
The task is of interest to researchers in the areas of information retrieval, multimedia content analysis, social media analysis, event detection and event-based multimedia indexing.

The data set comprises URL of images available on Flickr (approximately 167k images in total), together with their accompanying metadata such as tags, time and location information, etc. (in an XML format).

Ground truth and evaluation
Ground truth information will record the true media-event associations and will be generated by the organizers. The results of event-related media item detection will be evaluated with Precision-Recall-Fscore and Normalized Mutual Information.

Task schedule
2 May: Development set release
17 July: Test set release
14 September: Run submission deadline (extended)
19 September: Release of results (extended)

Recommended reading
Raphaël Troncy, Bartosz Malocha and André Fialho. Linking Events with Media. In the Open Track of the Linked Data Triplification Challenge, co-located with the 6th International Conference on Semantic Systems (I-SEMANTICS'10), Graz, Austria, September 1-3, 2010,

S. Papadopoulos, C. Zigkolis, Y. Kompatsiaris, and A. Vakali. Cluster-based Landmark and Event Detection on Tagged Photo Collections. In IEEE Multimedia, 2011.

S. Papadopoulos, R. Troncy, V. Mezaris, B. Huet, I. Kompatsiaris, "Social Event Detection at MediaEval 2011: Challenges, Dataset and Evaluation", Proc. MediaEval 2011 Workshop, Pisa, Italy, September 2011.

Task organizers:
Raphael Troncy, Eurecom, France
Vasileios Mezaris, ITI Certh, Greece

This task is made possible by a collaboration of projects including:

Glocal Project Logochorus+_logo
socialsensor logo