High Frame Rate (HFR) compression efficiency and backwards compatibility using HEVC

Abstract

[EN] Current UHD services use barely a couple of enhancement features compared to HD formats, by increasing spatial resolution and pixel bit-depth, which are insufficient to improve user experience when using large screens. This could led to a certain frustration on consumers, arising the fear that 4K technology could fail in the medium term as recently happened with 3DTV services. Aware of this, the audiovisual industry is involved in the agreement of the new generation of UHD, so-called UHD-1 Phase-2, which improves the immersive viewing experience features, such as Wider Color Gamut (WCG), High Dynamic Range (HDR), and High Frame Rate (HFR) technologies. ¿ In this paper, we focus on the encoding of HFR formats, which provides a crystal clear image, avoiding effects such as image blurring in scenes with high-motion, especially for sports and fast-action content. We describe the temporal scalability mechanism implemented in the HEVC standard, which can be useful for the encoding of HFR services in a backward-compatible manner, avoiding the need to carry out the simulcast of the same UHD service with different temporal resolutions. The HEVC coding efficiency for UHD@120Hz services is also reported, showing the bandwidth requirements for DVB-T2 and ATSC 3.0 networks. ¿ Finally, we describe the trial carried out at the University Campus, by broadcasting a scalable UHD@120Hz service using a DVB-T2 network, which proves backward-compatibility of the HFR services with the current UHD-1 TV sets, and also shows the HFR compatibility over low performance devices such as tablets and smartphones with low frame rates capabilities, by using in-home WiFi streaming.