Research & Development

What we're doing

BBC R&D - High Dynamic Range in Live TV Production - 2019 FA Cup Trials

BBC R&D - World Cup 2018 in UHD HDR on BBC iPlayer

BBC R&D - How to Adjust Your TV to Enjoy the Best Picture Quality in HDR

Consumer television displays are getting brighter and capable of presenting stunning UHD images which are almost like looking through a window on to a scene. Having seen some fantastic HDR demonstrations we wanted to understand how our viewers could benefit from HDR in the future.

Broadcast television, and particularly live television, has a very complex content workflow. Our production and broadcast activities are spread over a number of sites, each at different points in their equipment replacement cycle. We started to investigate how HDR could fit into a typical broadcast infrastructure such as ours. We concluded that any approach couldn't rely on end-to-end metadata as metadata often gets lost or becomes out-of-sync with the content as it passes through the production chain and that standard presentation techniques such as mixing video sources become overly complex with metadata. We also wanted the captured signal to be display-independent because a wide range of different displays and lighting conditions are used both in production environments and in the home. Finally we wanted an approach that was compatible with our current 10 bit infrastructure and only needed changes to the cameras and critical monitoring displays. This led us, and NHK who shared many of our concerns, to invent the Hybrid Log-Gamma (HLG) system for HDR.

In order to meet all of our requirements, HLG was designed to be a scene-referred system, just like conventional television. The signal represents relative light levels in the original scene, which allows pictures from a single mastering process or live production to be adapted to give the same artistic effect on brighter or darker screens at home. Only the display itself needs information about its own capabilities and environment to faithfully render the scene-referred signal, so metadata that describes the mastering display is not required. HLG also has native compatibility with standard dynamic range (SDR) television within the same colour format, which can be used for ultra-high definition (UHD) SDR displays.

We are working to develop a complete HDR ecosystem. This starts with fundamental research into the human visual system, which then informs development of technical systems including format conversion techniques, HDR production guidelines and adaptation requirements for displays of different brightness. We then see these systems through to international standards that cover the whole video chain, from the basic video parameters, through professional interfaces, compression, programme delivery and broadcast and IP distribution. We also support consumer electronics manufacturers in verifying their implementations and developing consumer interfaces to the final display. HLG is included in ITU-R BT.2100, the international standard for high dynamic range programme production and exchange, and is royalty-free.

BBC R&D - 4k UHD Trial of Planet Earth II in HDR

Why it matters

High Dynamic Range will offer a step-change in quality to viewers, making pictures more realistic and more immersive. In order for HDR programmes to be enjoyed in the home, a complete broadcast infrastructure must be in place. HLG's native compatibility allows much of the existing SDR infrastructure to be re-used for HDR.

How it works

We continue to add and link to a series of guides below, which describe the technical details of HDR and HLG in particular..


Quite simply, our audiences will be able to enjoy a brilliant home TV experience.

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BBC R&D - 2016 in Review - High Dynamic Range

BBC R&D - A Major Milestone for HDR TV

BBC R&D - HDR at the SES Industry Days

BBC R&D - London's New Year's Eve Fireworks in UHD and HDR

BBC R&D - EBU/DVB HDR Workshop

BBC R&D - 2014 Ultra-High Definition Trials

BBC R&D - Defining the Future of Television

UHD Production Training and Skills from the BBC Academy including:

UHD production: What do I need to know?

4K and Ultra-HD: Making Programmes Podcast

What does the future hold for UHD?

BBC News - BBC tests 4K Planet Earth II in HDR on iPlayer

Pocket-lint - BBC iPlayer gets Ultra HD, Planet Earth II trial in 4K HLG

T3 - Watch Planet Earth II in UHD 4K HDR on BBC iPlayer today

Wired - BBC iPlayer to show Planet Earth II in 'unprecedented' Ultra HD

Streaming Media Europe - BBC Streams FIFA World Cup

Recombu - What is BBC HLG and how can I watch it?

This project is part of the Broadcast and Connected Systems section

This project is part of the Immersive and Interactive Content section


People & Partners

Project Team

Project Partners