Understanding User Behavior in Volumetric Video Watching: Dataset, Analysis and Prediction

TL;DR

This paper introduces a large-scale volumetric video viewing behavior dataset, analyzes user interaction patterns, and proposes a transformer-based model for viewport prediction to enhance streaming efficiency.

Contribution

First to release a comprehensive volumetric video user behavior dataset, providing insights and a predictive model to optimize streaming based on user interactions.

Findings

User viewport and gaze behaviors vary significantly across videos and users.

The transformer-based prediction model achieves high accuracy in viewport prediction.

Analysis reveals key user preferences in volumetric video viewing.

Abstract

Volumetric video emerges as a new attractive video paradigm in recent years since it provides an immersive and interactive 3D viewing experience with six degree-of-freedom (DoF). Unlike traditional 2D or panoramic videos, volumetric videos require dense point clouds, voxels, meshes, or huge neural models to depict volumetric scenes, which results in a prohibitively high bandwidth burden for video delivery. Users' behavior analysis, especially the viewport and gaze analysis, then plays a significant role in prioritizing the content streaming within users' viewport and degrading the remaining content to maximize user QoE with limited bandwidth. Although understanding user behavior is crucial, to the best of our best knowledge, there are no available 3D volumetric video viewing datasets containing fine-grained user interactivity features, not to mention further analysis and behavior prediction. In this paper, we for the first time release a volumetric video viewing behavior dataset, with a large scale, multiple dimensions, and diverse conditions. We conduct an in-depth analysis to understand user behaviors when viewing volumetric videos. Interesting findings on user viewport, gaze, and motion preference related to different videos and users are revealed. We finally design a transformer-based viewport prediction model that fuses the features of both gaze and motion, which is able to achieve high accuracy at various conditions. Our prediction model is expected to further benefit volumetric video streaming optimization. Our dataset, along with the corresponding visualization tools is accessible at https://cuhksz-inml.github.io/user-behavior-in-vv-watching/