See the next THUMOS Challenge, 2015!

The ground truth labels of the test data is available HERE!

THUMOS 2014 Challenge results are available HERE!

Action Recognition in Temporally Untrimmed Videos!

Automatically recognizing and localizing a large number of action categories from videos in the wild of significant importance for video understanding and multimedia event detection. THUMOS workshop and challenge aims at exploring new challenges and approaches for large-scale action recognition with large number of classes from open source videos in a realistic setting.

Most of the existing action recognition datasets are composed of videos that have been manually trimmed to bound the action of interest. This has been identified to be a considerable limitation as it poorly matches how action recognition is applied in practical settings. Therefore, THUMOS 2014 will conduct the challenge on temporally untrimmed videos. The participants may train their methods using trimmed clips but will be required to test their systems on untrimmed data.

A new forward-looking dataset containing over 254 hours of video data and 25 million frames with the following components is made available under this challenge:

  • Training Set: over 13,000 temporally trimmed videos from 101 action classes.
  • Validation Set: Over 1000 temporally untrimmed videos with temporal annotations of actions.
  • Background Set: Over 2500 relevant videos guaranteed to not include any instance of the 101 actions.
  • Test Set: Over 1500 temporally untrimmed videos with withheld ground truth.
  • Spatio-temporal Annotations: Bounding box annotation for 24 action classes.

All videos are collected from YouTube, and their pre-extracted low-level features (Improved Dense Trajectory Features) are made available.

The entries to the challenge will be evaluated using the new THUMOS 2014 Dataset in two tasks:

  1. Action Recognition: accepts submissions for whole-clip action recognition over 101 classes.
  2. Temporal Action Detection: accepts submissions on action recognition and temporal localization on 20 action classes.

Participants may either submit a notebook paper (due September 4th) that briefly describes their system, or a research paper detailing their approach. All of the submission results will be summarized during the workshop and included in the workshop\conference proceedings. Additionally, the top performers will be invited to give oral presentations, and the remaining participants are encouraged to present their work in the poster session.

For more details, please see the Evaluation Setup document or the released resources.

See the last THUMOS Challenge: THUMOS 2013
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[10/14/2014] The videos of the talks are now available.

[10/08/2014] The notebook papers are available HERE!

[10/08/2014] The challenge summary presentations are available HERE!

[10/03/2014] The ground truth labels of the test data is available HERE!

[09/05/2014] THUMOS 2014 Challenge results are available HERE!

[08/29/2014] The tentative program is posted.

[08/18/2014] The test set is released. The submission deadline is Aug. 30, 2014 11:59 PST.

[07/31/2014] Fast download links are added to the website.

[07/30/2014] The development kit is now available.

[07/30/2014] The second part of the data (includding pre-extracted features, background videos, temporal annotations) was released.

[07/19/2014] The first part of the training data was released.

[5/2014] Website launched.

Mailing List

  • Join our mailing list to receive updates and information about the event by clicking here.

Important Dates

  • ✔ Training Data Release 1 (Training+Validation videos, features, evaluation setup): Jul. 18, 2014
  • ✔ Training Data Release 2 (Development kit, Temporal Annotations): Week of Jul. 21, 2014
  • ✔ Test Data Release: Aug. 15, 2014
  • ✔ Submission Deadline: Aug. 30, 2014
  • ✔ Challenge Results Notifications: Sept. 3, 2014
  • ✔ Workshop date: Sept. 7, 2014
  • Publication date: As per conference schedule

Program Chairs

General Chairs