On the Compression Performance of HEVC, VP9 and AV1 Encoders for Virtual Reality Videos
Ladislav Polák, Jan Kufa, Tomáš Kratochvíl · 2020
Thanks to advances in display technologies and affordable end user devices, interest in Virtual Reality (VR) and related multimedia content, namely 180° and 360° images and videos, has been rapidly increasing in recent years. For effective delivery of a video in such format, compression algorithms with high efficiency are vital. In this paper, the outputs of a subjective-based compression performance study of recent (HEVC and VP9) and emerging (AV1) video coding formats for 180°/360° videos are presented. Viewers' Quality of Experience (QoE) is assessed by subjective tests utilizing Absolute Category Rating with Hidden Reference (ACR-HR) protocol. In addition, these tests, wherein two different Head Mounted Devices (HMDs) from Oculus were used, are extended with a custom questionnaire that helps to better understand observers' experience and feelings with VR. Results revealed that not only the quality levels (bit rates) of the compressed 180°/360° videos have influence on the viewers' perceived QoE.