Robert Skupin

Robert Skupin, Christian Bartnik, Adam Wieckowski et al.

The user experience in adaptive HTTP streaming relies on offering bitrate ladders with suitable operation points for all users and typically involves multiple resolutions. While open GOP coding structures are generally known to provide substantial coding efficiency benefit, their use in HTTP streaming has been precluded through lacking support of reference picture resampling (RPR) in AVC and HEVC. The newly emerging Versatile Video Coding (VVC) standard supports RPR, but only conversational scenarios were primarily investigated during the design of VVC. This paper aims at enabling usage of RPR in HTTP streaming scenarios through analysing the drift potential of VVC coding tools and presenting a constrained encoding method that avoids severe drift artefacts in resolution switching with open GOP coding in VVC. In typical live streaming configurations, the presented method achieves -8.57% BD-rate reduction compared to closed GOP coding while in a typical Video on Demand configuration, -1.89% BD-rate reduction is reported. The constraints penalty compared to regular open GOP coding is 0.65% BD-rate in the worst case. The presented method was integrated into the publicly available open source VVC encoder VVenC v0.3.

Dimitri Podborski, Jangwoo Son, Gurdeep Singh Bhullar et al.

Virtual Reality (VR) and 360-degree video streaming have gained significant attention in recent years. First standards have been published in order to avoid market fragmentation. For instance, 3GPP released its first VR specification to enable 360-degree video streaming over 5G networks which relies on several technologies specified in ISO/IEC 23090-2, also known as MPEG-OMAF. While some implementations of OMAF-compatible players have already been demonstrated at several trade shows, so far, no web browser-based implementations have been presented. In this demo paper we describe a browser-based JavaScript player implementation of the most advanced media profile of OMAF: HEVC-based viewport-dependent OMAF video profile, also known as tile-based streaming, with multi-resolution HEVC tiles. We also describe the applied workarounds for the implementation challenges we encountered with state-of-the-art HTML5 browsers. The presented implementation was tested in the Safari browser with support of HEVC video through the HTML5 Media Source Extensions API. In addition, the WebGL API was used for rendering, using region-wise packing metadata as defined in OMAF.