For a few days we have been telling you what the different HDR formats consist of. We have talked about HDR10, the standard that we find in all devices. We have also talked about Dolby Vision, which is increasingly present. And yesterday we told you what Technicolor is, a European standard that seeks, of course, to optimize the image. Today is the turn of HLG, the HDR standard for television broadcasts .
What is HLG?
As we have seen, the different HDR formats are present both in UHD Blu-Ray optical discs and in streaming services. However, what about television broadcasts?
This is where the HLG comes in. The Hybrid Log Gamma (HLG) standard aims to bring HDR to live television broadcasts . It is a project that is being developed by the BBC television networks in the United Kingdom and NHK in Japan. At the moment it is a system in development, with the goal set at the 2020 Tokyo Olympics.
But why is a special standard necessary? According to BBC technicians, current HDR technology is very sensitive to interference and loss of connection . And it's no wonder, because both HDR10 and Dolby Vision use metadata to tell TVs how to display the image. This system can be used for prepared content such as movies or series, but not for live broadcasts.
Therefore it began to develop the system HLG, which combines standard dynamic range images and high dynamic range images into a single video signal . This is played as SDR on normal displays and as HDR on HLG compatible displays.
A good example of what the HLG is capable of is seen in the broadcast of a football match in which we have sunny areas of the pitch and shady areas. The HDR system is capable of displaying maximum detail in both areas .
How can I see HLG?
That the HLG system mixes the SDR signal with the HDR signal does not mean that we do not need a compatible equipment to reproduce it. To view the images in HLG format we need a compatible television .
Luckily most manufacturers, including LG, have confirmed that their televisions will be compatible with HLG . And not just the newer models, but the 2017 models and even some 2016 models, thanks to a firmware update.
Some projectors will also include this system, especially high-end models. Even Android TV will incorporate HLG in its version 7.0 .
What content is available on HLG?
The HLG system is intended for terrestrial, cable and satellite television broadcasts. Still, we still have practically no content on this system .
Until recently, only a few tests had been broadcast at tech fairs and press events. On the other hand, the BBC broadcast in December 2016 a four-minute clip of Planet Earth II in 4K and HLG .
In December 2017, the BBC released all seven episodes of Blue Planet II in 4K and HLG on its iPlayer service . However, this content only lasted 30 days on the platform.
Regarding the Spanish market, Mediapro announced its intention to broadcast the Spanish football league on HLG . On the other hand, Google has ensured that HDR YouTube videos will support HLG encoding. Even some satellite TV providers like Sky or Eutelsat will have some channels dedicated to HLG.
No doubt a lot for the HLG system is normal emissions from all countries . Even more so if we talk about public television. Possibly many of us have changed televisions when this arrives.
So if you have a television that is a couple of years old, don't worry that they don't have the HLG format. However, if we are going to buy a new TV, it would be interesting to make sure that it will include the HLG format , even through a software update.