AVTrack360: An open Dataset and Software recording people's Head Rotations watching 360° Contents on an HMD

n this paper, we present a viewing test with 48 subjects watching 20 different entertaining omnidirectional videos on an HTC Vive Head Mounted Display (HMD) in a task-free scenario. While the subjects were watching the contents, we recorded their head movements. The obtained dataset is publicly available in addition to the links and timestamps of the source contents used. Within this study, subjects were also asked to fill in the Simulator Sickness Questionnaire (SSQ) after every viewing session. Within this paper, at first SSQ results are presented. Several methods for evaluating head rotation data are presented and discussed. In the course of the study, the collected dataset is published along with the scripts for evaluating the head rotation data. The paper presents the general angular ranges of the subjects' exploration behavior as well as an analysis of the areas where most of the time was spent. The collected information can be presented as head-saliency maps, too. In case of videos, head-saliency data can be used for training saliency models, as information for evaluating decisions during content creation, or as part of streaming solutions for region-of-interest-specific coding as with the latest tile-based streaming solutions, as discussed also in standardization bodies such as MPEG.