Overview of 360-Degree Video and Viewport Prediction

doi:10.3778/j.issn.1002-8331.2305-0056

Abstract

Abstract: 360-degree video is one of the convenient media to obtain immersive virtual reality experience, which has attracted wide attention in recent years. Viewport prediction technology is an important means to alleviate the high bandwidth requirement of 360-degree video network, focusing viewport prediction technique, the basic concept of 360-degree video, background and 360-degree video streaming framework are firstly introduced, and the common sphere to plane projection methods and video codec standards are compared. The disadvantage of 360-degree video high network resource consumption is analyzed, and the important role of viewport prediction technology for video streaming is introduced. The 360-degree attention dataset is introduced, and the mainstream public datasets are summarized. The existing viewport prediction methods are divided into user history track based method and video content-based method, and a systematic review is carried out to sort out the development of viewport prediction methods, introduce the latest work of viewport prediction methods, compare the characteristics, advantages and limitations of different methods, and briefly introduce the 360-degree image salient detection. 360-degree salient detection is the focus of viewport prediction method based on video content. Finally, the problems faced by viewport prediction methods are analyzed, and the future development trend of 360-degree video related technologies including viewport prediction methods is forecasted.

Key words: 360-degree video, panoramic video, viewport prediction, saliency detection, deep learning, virtual reality

摘要： 360度视频是获取沉浸式虚拟现实体验的便捷媒介之一，近年来受到了广泛关注。视口预测技术是缓解360度视频高网络带宽要求的重要手段。聚焦视口预测技术，首先介绍360度视频的基本概念、背景和360度视频流式框架，对比常用的球面到平面投影方法、视频编解码标准；分析360度视频高网络资源消耗的原因，体现视口预测技术对360度视频流式的重要作用；介绍360度注意力数据集，总结主流公开数据集；将现有的视口预测方法，分为基于用户历史轨迹的方法和基于视频内容的方法，进行系统性的综述，梳理视口预测方法的发展脉络，介绍视口预测方法的最新工作，比较不同方法的特点、优势和不足，并简略介绍了360度显著性检测，360度显著性检测是基于视频内容的视口预测方法中的重点。最后进行总结，分析了现阶段视口预测方法面临的问题，展望了包括视口预测方法在内的360度视频相关技术的未来发展趋势。

关键词: 360度视频, 全景视频, 视口预测, 显著性检测, 深度学习, 虚拟现实

LI Zhenhuai, ZHAN Yinwei. Overview of 360-Degree Video and Viewport Prediction[J]. Computer Engineering and Applications, 2024, 60(2): 19-31.

李镇淮, 战荫伟. 360度视频与视口预测方法综述[J]. 计算机工程与应用, 2024, 60(2): 19-31.

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