EN FR
EN FR
STARS - 2014
Overall Objectives
New Software and Platforms
New Results
Bilateral Contracts and Grants with Industry
Bibliography
Overall Objectives
New Software and Platforms
New Results
Bilateral Contracts and Grants with Industry
Bibliography


Section: New Results

Action Recognition using Video Brownian Covariance Descriptor for Human

Participants : Piotr Bilinski, Michal Koperski, Slawomir Bak, François Brémond.

keywords: action recognition, computer vision, machine learning

This work addresses a problem of recognizing human actions in video sequences. Recent studies have shown that methods which use bag-of-features and space-time features achieve high recognition accuracy [61] , [93] , [42] . Such methods extract both appearance-based and motion-based features. In image processing, a novel trend has emerged that ignores explicit values of given features, focusing instead on their pairwise relations. The most known example of such an approach is covariance descriptor [92] . Inspired by Brownian motion statistics [88] and application in people Re-identification [35] ; we propose to model relationships between different pixel-level appearance features such as intensity and gradient using Brownian covariance, which is a natural extension of classical covariance measure. While classical covariance can model only linear relationships, Brownian covariance models all kinds of possible relationships. We propose a method to compute Brownian covariance on space-time volume of a video sequence. We show that proposed Video Brownian Covariance (VBC) descriptor carries complementary information to the Histogram of Oriented Gradients (HOG) descriptor. The fusion of these two descriptors gives a significant improvement in performance on three challenging action recognition datasets. The result of this work was published in proceedings of the 11th IEEE International Conference on Advanced Video and Signal-Based Surveillance, AVSS 2014 [38] .

Figure 26. Comparison between Covariance and Brownian distance correlation. Covariance values in black, Brownian values in red.
IMG/brownian_covariance.png