The ITU-R HDR-TV Recommendation BT.2100 builds on UHDTV BT.2020, which was adopted in 2015. It is intended to ensure that television programming makes full use of the advantages of new and significantly brighter display technology with a wider dynamic range. HDR TV is intended to make outdoor scenes illuminated by sunlight appear much brighter and more natural and to improve dimly lit interiors and night shots by making more detail visible in dark areas.
2 Specifications
Two specification options are available for producing HDR TV: the Perceptual Quantization (PQ) specification achieves a wide brightness range through a transfer function tuned to human perception. By contrast, the Hybrid Log-Gamma (HLG) specification offers compatibility with previous displays to a certain degree and conforms more closely to the common TV transfer curve. The ITU recommendation also describes a simple conversion process between these two HDR-TV options.
Three Resolution Levels
With the new standard, TV producers can choose between three resolution levels for production: HDTV (1,920 x 1,080), UHDTV 4K (3,840 x 2,160) and UHDTV 8K (7,680 x 4,320), all of which use progressive display with an extended colour space and a frame-rate range in the ITU’s UHDTV Recommendation BT.2020.
More about the new Rec.2100 standard for HDR TV can be found in this PDF from the ITU.
HDR in Current Practice
While the train in terms of hardware, content and HDR-capable interfaces is, as usual with new standards, only gaining momentum extremely slowly, Netflix and Amazon Prime already see HDR as the next “big thing”. “Marco Polo” is the first series already “available” in HDR (hardly anyone will actually be able to watch it in HDR because of the lack of devices and transmission paths). HDR displays are already used particularly in the medical field, because with X-ray images in particular it is crucial to be able to recognise the smallest structures. While some hardware manufacturers proclaim that they sell HDR-capable devices, these still do not use the defined standard. HDR output is currently still in development and is interpreted relatively freely, similar to what happened with HD-ready devices at the time.
Archive notice: This article was originally published on July 13, 2016. Links and embedded videos are preserved as part of the historical record.
