Application of HEVC and DVB-T2 to terrestrial 4K UHDTV broadcast over-the-air trials

Abstract

The sense of presence in UHDTV(Ultra High Definition TV) mainly arises from a wide field of view combined with ultra high definition resolution and an extremely fine picture quality. Therefore, UHDTV requires a resolution of 4K(3840x2160) or 8K(7680x4320) pixels. Furthermore, to provide a more vivid picture, UHDTV goes as far as a frame-rate of 120fps, a wider colour gamut and a colour-depth of 12 bits. For this reason, UHDTV necessarily results in an extremely huge amount of data. Even many experts have questioned whether the 6MHz or 8MHz bandwidth of a terrestrial TV channel offers realistic possibilities for UHDTV transmission. In Korea, the KBS(Korean Broadcasting System) carried out the world's first terrestrial 4K 30p UHDTV experimental broadcast from 9th October to 31st December 2012. The most prominent feature of this broadcasting was the use of a terrestrial TV channel. To fit the extremely high video datarate into its limited bandwidth, we exploited HEVC (High Efficiency Video Coding) compression and DVB-T2 transmission and reception systems. In this paper, we shall give an overview of KBS' 4K-UHDTV experimental broadcast and explain 4K-UHDTV content compression with an HEVC codec and the DVB-T2 system used in the trial. In addition, we shall show the result of our optimisation tests on HEVC coding of 4K 60p UHDTV.