If you’re looking for a new 4K ultra-high definition TV, it almost certainly supports High Dynamic Range (HDR) video. But what is the difference between competing HDR formats? Should you take this into account in your purchase?
What is HDR?
HDR stands for high dynamic range. It refers only to the visual presentation of movies, TV shows, video games or pictures. In essence, HDR provides a better, brighter picture with more detail than a standard definition video or picture.
While standard definition (or SDR) content is limited to eight bits per channel of color information, HDR uses 10-bit color as a reference (some standards support up to 12-bit). Higher color depth means more shades of the same color, which greatly reduces a phenomenon called “banding”.
Video presented in 8-bit color is limited to 256 shades per channel, while HDR video increases it to 1024. This results in smoother transitions between different shades of the same color for a more realistic picture. This also applies to grays, improving near-black performance for better detail in shadows and low-light scenes.
In addition to the wider color gamut, high dynamic range video also affects the overall brightness of the image. SDR video is mastered at 100 nits of maximum brightness, a level that all standard definition displays are designed to achieve. HDR video is mastered at a much higher peak brightness of 1000 nits or more, depending on the format.
This means that HDR content can become much brighter, for a more realistic picture. This does not mean that the whole scene is always much brighter than SDR video, but rather individual elements. It could be a candle in the dark, the sun, or the flash of an explosion.
To truly understand what makes HDR so much better than SDR, you have to experience it.
HDR10: the “standard” implementation
HDR10 is the base standard on all HDR compatible televisions. If you buy a 4K Ultra-HD Blu-ray with an “HDR” sticker, it will be shown in HDR10. Some of these Blu-rays also support other HDR standards. However, HDR10 is the “compatibility mode” that all TVs can fall back on.
Content produced for HDR10 is mastered at up to 1000 nits of peak brightness. It uses static metadata to set the frame’s average light levels and maximum brightness, which helps your TV understand how to present the entire production. Although HDR10 is the “standard” HDR format, it will still be significantly better than SDR content.
Since HDR10 is an open format, it also enjoys a wide range of media from TV and display manufacturers and content producers. 10-bit cameras, like the Panasonic GH-5s, and displays that can reach 1000 nits of peak brightness, have made producing HDR10 content much more accessible than it once was.
As a result, you’ll find HDR10 content everywhere, including a lot of free content on YouTube. While there are hardly any standards for HDR gaming, consoles and Windows also use HDR10 to deliver high dynamic range gaming.
HDR10 +: Enhanced HDR with dynamic metadata
HDR10 + is another open standard, but it’s produced by Samsung and Amazon Video. It enhances HDR10 by using dynamic metadata that can adjust luminance on a per scene or frame by frame basis. Content produced in HDR10 + is currently under control at up to 4000 nits of peak brightness. This means that HDR10 + content can be much brighter than HDR10.
The HDR10 + standard is also equipped to support video up to 16-bit color depth, 8K resolution, and maximum brightness of 10,000 nits. However, to date, no content has been produced that even comes close to these specifications.
The biggest problem with the HDR10 + is its lack of availability. Currently, Samsung is the only major manufacturer to do so, although support from Panasonic, Vizio and Oppo is limited.
Content is also scarce: currently only Amazon Video offers streaming content in HDR10 +.
Dolby Vision: a proprietary format with dynamic metadata
Dolby Vision is a direct competitor to HDR10 +, and it shares many similarities from a technical standpoint. Current Dolby Vision content is mastered at brightness up to 4000 nits, but it will support up to 10,000, as well as 8K resolution in 12-bit color, in the future. It also uses dynamic metadata for scene-by-scene adjustments to improve overall picture quality.
Since Dolby Vision is a proprietary format, TV manufacturers have to pay to implement it. It’s mostly found on high-end TVs, but it has been widely adopted by LG, Sony, TCL, Hisense, Panasonic, and Philips. Samsung is the only notable manufacturer to have avoided Dolby Vision entirely in favor of HDR10 +.
If you are really looking, there are TVs that support all formats. However, HDR10 + is significantly more difficult to find than Dolby Vision. There is also simply a lot more content available in Dolby Vision. Many Netflix and Disney + shows are produced in Dolby Vision, with support for some shows on services like Amazon Prime Video and VUDU.
As Dolby Vision is closely tied to content produced for Dolby Cinemas, this has likely given the format the necessary boost for widespread support among content producers.
There is also support for Dolby Vision in the Xbox Series X and Series S, which promise to deliver the first Dolby Vision gaming experiences in 2021. We’ll have to wait and see how that plays out, but it’s something to keep. in mind if you ‘will be buy a next-gen Xbox anytime soon.
Hybrid Log-Gamma: the broadcast standard
Broadcast standards evolve differently from production standards, but that doesn’t mean staying true to SDR forever. Hybrid Log-Gamma (HLG) is an open streaming format developed by the BBC in the UK and the NHK audience in Japan. It is a backward compatible format that implements HDR video streaming. HLG specifically targets a maximum brightness of 1000 nits, like HDR10.
Since broadcasts have to consider such a wide range of devices with different capacities, it is essential to ensure that modern HDR broadcasts display correctly on older SDR screens. HLG accomplishes this by providing a signal that allows modern HDR displays to achieve greater dynamic range without closing the door on older technology.
Although this format was created for broadcasts, it is also supported by streaming services, including YouTube and BBC iPlayer. Broadcasters already using HLG include Eutelsat, DirecTV, and Sky U.K.
Advanced HDR by Technicolor: Dead on Arrival
One HDR format that failed to capture any audiences was Technicolor’s Advanced HDR. Launched by LG and Technicolor, the format first appeared around 2016. It made its way into LG TVs until 2019, when the company abruptly removed support for the format from its 2020 lineup. It effectively killed off. technology.
The main problem with Technicolor’s efforts was the lack of content. As of September 2020, we couldn’t find a single movie for sale mastered in Advanced HDR or any streaming service that supports it. This makes Technicolor’s Advanced HDR the HD-DVD of HDR.
What format should you invest in?
If you buy an HDR TV in 2020 (or beyond), it will support HDR10, which is a huge leap forward in dynamic range and brightness compared to standard definition content. If you haven’t experienced HDR10 content yet, you’re in for a treat! To enjoy it, you’ll need a TV with close to 1000 nits of brightness and controlled content to enjoy it.
Beyond HDR10, Dolby Vision enjoys the broadest support among content producers and TV manufacturers. More Blu-ray and streaming services are available in Dolby Vision. The format is also quite scalable, as we won’t see the best it has to offer until display technology develops further. However, Roku and Google will release streaming boxes that support Dolby Vision this year.
There are also plenty of TVs to choose from that support Dolby Vision, while HDR10 + support is mostly limited to Samsung. Vizio and Hisense produce TVs that support both, but not all models. In addition, very few movies are mastered in HDR10 + and only Amazon produces streaming content for this.
Because HLG is a broadcast standard, most modern TVs will support it in the future. However, your display does not need to support HLG for you to receive broadcasts. If you don’t watch network TV or cable a lot, you may want to put HLG at the bottom of your priority list.
In most cases, the TV you choose will dictate the standards you can enjoy. In view of this, you will also want to understand the difference between display technologies so that you can make an informed choice.