Multi Player Tracking in Ice Hockey with Homographic Projections

TL;DR

This paper introduces a novel multi-object tracking method for ice hockey that uses homographic projections to improve player localization and identity maintenance in challenging broadcast video conditions.

Contribution

The work formulates MOT as a bipartite graph matching problem with homography, disentangling occluded players by projecting their foot keypoints onto an overhead rink template.

Findings

Significant improvements in IDsw and IDF1 metrics.

Effective handling of occlusions and overlaps in broadcast feeds.

Enhanced spatial context for consistent tracking.

Abstract

Multi Object Tracking (MOT) in ice hockey pursues the combined task of localizing and associating players across a given sequence to maintain their identities. Tracking players from monocular broadcast feeds is an important computer vision problem offering various downstream analytics and enhanced viewership experience. However, existing trackers encounter significant difficulties in dealing with occlusions, blurs, and agile player movements prevalent in telecast feeds. In this work, we propose a novel tracking approach by formulating MOT as a bipartite graph matching problem infused with homography. We disentangle the positional representations of occluded and overlapping players in broadcast view, by mapping their foot keypoints to an overhead rink template, and encode these projected positions into the graph network. This ensures reliable spatial context for consistent player tracking and unfragmented tracklet prediction. Our results show considerable improvements in both the IDsw and IDF1 metrics on the two available broadcast ice hockey datasets.