The time has come to set the standards. An EBU perspective by Dr Hans Hoffmann, Adi Kouadioand Yvonne Thomas
WHAT COMES after HDTV? Many broadcasters are still in the implementation phase for HDTV and this will remain the main focus in production and distribution for EBU Members for the coming years. That said, very soon new products will enter the market with resolutions beyond that of current HDTV. They — and the manufacturers that promote them — promise to give the consumer a significantly enhanced viewing experience. For broadcasters planning their
future investments, it’s crucial to be able to choose a format that is future-proof; and competition factors may even force some to move on sooner than planned from the just-introduced HD formats. To make an informed decision, they need a clear unbiased assessment of the available formats, an understanding of their financial implications and, most
Hans Hoffmann: Content-wise the focus is increasingly on event programming rather than 24/7 linear output
importantly, an insight into what value these formats will add for viewers. The EBU is well positioned to deliver this information and more. Let’s start with S3D,
Stereoscopic 3DTV. In cinemas, well-made stereoscopic content has made the breakthrough. In broadcast, on the other hand, even though the production of content is improving, a global market breakthrough hasn’t happened. This is due to lack of content, the need for glasses, and so forth. Some of the distribution issues have now been solved by
DVB and it’s up to the industry to implement standards supporting, for example, 1080p/50 3D content per eye. Content-wise the focus is increasingly on event programming rather than 24/7 linear output. Then we have UHDTV, Ultra High Definition. This has really come to the fore with the London Olympics, where NHK, with BBC and OBS, delivered stunning content in Super Hi-Vision. UHDTV is defined by the ITU and SMPTE into two resolutions. For the benefit of this article we’ll call them UHD-1 (3840x2160
pixel) and UHD-2 (7680x4320 pixel, NHK’s Super Hi-vision). UHD-1 is four times HD resolution (hence the term QuadHD), and consumer displays are just coming to market. (It’s sometimes called 4k, which can be misinterpreted as the Digital Cinema 4k format of 4096x2160.) Even for UHD-2, which is eight times HD, we already see prototype consumer displays. These resolutions allow viewers to see much greater detail at viewing angles up to 100° and viewing distances as low as 1.5 times the picture height (for UHD-2). The recent ITU-R recommendation foresees higher frame rates than conventional 50/60Hz, proposing up to 120Hz, plus wider colour gamut and higher bit-depth up to 14 bit.
So what’s missing? Thanks to the consumer electronics industry we’ll soon see the promotion of screens with UHD-1 resolution. But some open questions remain. In the first place we should look at business models: content creation issues along with the source and production formats; the means to move UDH-1/UHD-2 in realtime and non realtime from the source to the home; and,
importantly, the added value that will convince consumers to take an interest and invest. Then, on the technology side,
it’s key that we reach a point where we have equipment that operates according to standards, in an end-to-end chain (interfaces, compression, exchange technologies) at the lowest cost (storage, bandwidth). When it comes to interfaces we see that standards for UHD-1/2 are not yet available, whether for mainstream professional production (single link studio interfaces) or consumer (eg, one HDMI link) purposes. Equally the compression systems for production and distribution (HEVC — High Efficiency Video Coding) are just being introduced and their performance needs to be tested. It was to address the above questions that the EBU generated Tech Report 014 (from the Beyond HD group) and Tech Report 010 and R 135 (from the 3DTV group), providing guidance to senior management on 4k- 1080p/50 and 3DTV respectively. Furthermore, the groups have now generated a set of reference test material in 4k and in 3D (at 1080p/50 per eye and with higher frame rates up to 120Hz). The test materials were shot during June at the RAI Production Centre in Turin, with cooperation between RAI Research/Production Centres, EBU staff and Members and industry partners. (A full report on the Turin shoots can be found in the EBU’s tech-i magazine, which you can pick up from the EBU booth at IBC (10.F20), where you also have a chance to view some of the new sequences.) The new sequences will allow
EBU Members to conduct scientific tests and develop a deeper understanding of the added value of the new formats, initiating standardisation work as required. The EBU’s project groups will conduct further tests on the UHD-1 and 2 and 3DTV formats. In particular we’ll be looking at studio compression formats and the HEVC codec for distribution to the home. As usual, we will liaise closely with other key organisations such as the SMPTE, for interface standards, MPEG and the ITU. EBU Members can and should
be at the forefront of technology developments and help to prevent the adoption of de facto standards. The window of opportunity is open now for next generation TV formats, and we need to use our influence to ensure that the specific requirements of broadcasters are reflected.