High Dynamic Range (HDR) imaging is one of the most important current trends in home cinema. HDR images show a greater degree of contrast between dark and light for enhanced details and a more realistic effect.
Dolby Vision is a leading video processing technology for delivering HDR that leverages the ability of contemporary projection and screen technology to capture these differences. With Dolby Vision, it’s possible to enjoy HDR on televisions, computer screens, mobile devices and in cinemas. The technology can be delivered via broadcasters and even streamed. Read on to find out what this visual standard from the California sound experts has to offer.
What HDR means for televisions
An HDR-enabled television can achieve markedly higher contrast than standard LCD devices. To be considered an HDR TV, the following standards must be met:
- A minimum resolution of 3,840 x 2,160
- 10-bit colour depth: This refers to the colours contained in the video signal, in this case more than a billion
- Minimum 90% of DCI P3 colours
- Minimum dynamic range: 1,000 nits brightness and .05 nits black level or 540 nits brightness and .0005 nits black level
The effect of HDR TVcan be explained by using the example of a solar eclipse. On an HDR television, the moon that passes in front of the sun is displayed as a completely black disc. The corona, that bright aura around the sun that an eclipse makes so visible, is especially intense, just as it would be in real life. Unlike staring at the real thing, however, there is no associated danger of burning your eyes, which is nice.
Dolby does HDR with Dolby Vision
Dolby Vision is a visual standard for HDR TVs. Its unique feature is the use of dynamic metadata to continuously adjust the image. The word “dynamic” is key here. Unlike other image standards, Dolby Vision alters the contrast and colour saturation as the movie progresses for an energizing and lifelike image. In this, Dolby has created a similar effect with picture quality as it has with its sound formats: True-to-source reproduction. The idea is to deliver the picture exactly as it was recorded. Dolby Vision was even designed to compensate for HDR television models that tend to overdue the contrast effects for a realistic image no matter what device is used to display it.
Just as Dolby’s sound technologies are not alone on the market but exist side-by-side with similar offerings from DTS, Dolby Visual is not the only HDR standard on offer. HDR10 is a technology supported by Samsung and Sony. Initiated by them, HDR10 is an open standard and so does not require licensing like Dolby Visual. Other brands including Philips and LG have also produced televisions that support HDR10 and many manufacturers produce models that support both Dolby Visual and HDR10.
Of course, the two standards differ more than in simply which manufacturers offer them. Dolby Vision requires licensing from manufacturers but with the benefit of offering better HDR performance. HDR10, for instance, does not dynamically map image data – these are set for the length of a movie. The two standards also offer different levels of brightness with Dolby Vision reaching 10,000 nits and HDR10 achieving the minimum requirement for HDR televisions of 1,000 nits. The Dolby technology also attains a maximum colour contrast of 12 bit which is above the minimum 10 bit. (Nits are units of brightness first established in the standards for high-definition televisions.)
How does Dolby Vision sound?
Dolby’s new standard is one of the first truly exciting optimizations of home cinema picture quality in many years, but, as its name suggests, Dolby Visual s a visual technology. Sound quality it not affected. Instead, the sound you hear will depend on whichever standard your AV receiver or DVD/Blu-ray player support and what your streamed content or DVD delivers. Dolby 5.1 and True HD are popular options but the true sonic equivalent of Dolby Vision may well be Dolby Atmos. This object-based sound standard delivers an incomparably lifelike and lively experience. Instead of assigning effects to fixed channels, they become sound objects that fly through the room according to the action on the screen.
What do you need to experience Dolby Vision?
On the device side, you’ll need an HDR television. HDR TVs are able to individually adjust picture brightness. Organic Light-Emitting Diode (OLED) televisions such as LG offers are perfect choices as the diodes are able to adjust brightness levels for discreet areas of the picture. The disadvantage of this technology is the extremely high price tag. A more affordable alternative are televisions that employ LCD technology with special background illumination. Most TV manufacturers produce these models, but the theoretical ability to produce HDR images is not enough. The television must work with Dolby’s HDR standard. LG and Philips are two brands that currently offer Dolby Vision televisions.
In addition to a television that supports Dolby Vision, you’ll need content. In this, Dolby has its leg up on its rival by being based near Hollywood. Large movie studios like Universal, MGM and Warner all want to support Dolby Vision. The popular streaming service Netflix already produced the first series for Dolby Vision with “Marco Polo.” Amazon also offers compatible content with its streaming service. Ultra HD Blu-rays will be able to include the additional image data, but movies are not yet available in this format. Also, in order to enjoy HDR picture quality on Blu-ray, another device will be required in addition to an HDR TV: A Blu-ray player with HDR decoder.
Dolby Vision facts at a glance:
• Dolby Vision is a picture optimization standard for televisions that offers an especially high level of contrast
• The standard requires licensing unlike the competing standard championed by Sony and Samsung, HDR10
• As opposed to HDR10, Dolby Vision uses dynamic meta data to optimally adjust an image’s dynamics throughout the movie
• Dolby Vision has no influence on the sound format used
• Streaming providers like Netflix have been pioneers of this new picture technology
• Not all television manufacturers offer this new standard.