HDR format debate re-opened12 September 2016
A side-by-side demo of Hybrid Log-Gamma (HLG) and Dolby Vision on the Dolby stand at IBC could re-open the debate about which version of high dynamic range (HDR) is best suited to live television.
Using test footage shot separately by Sky Sports, BT Sport, and the BBC, the Californian manufacturer is attempting to show that, despite suggestions to the contrary, Dolby Vision is as applicable to live television as it is to recorded content such as movies.
In July, the ITU announced an industry-wide HDR standard that included both the HLG specification, developed by the BBC and NHK, and the PQ (Perceptual Quantisation) specification on which Dolby Vision is based. It has been suggested that HLG is more appropriate for a live broadcast environment, an idea refuted by Dolby.
Roland Vlaicu, vice president of consumer imaging, Dolby Labs, told The IBC Daily: “We heard that HLG is the format of choice for live broadcast.
Our point is, it doesn’t have to be. You can do everything with Dolby Vision and we’re showing that here.
The underlying signal representation for Dolby Vision, which is the international PQ standard ratified by SMPTE and ITU-R, is perfectly capable of delivering a superior HDR experience for live in a way that optimises the production effort.”
Vlaicu added that the PQ HDR camera output can also be rendered for standard dynamic range (SDR) using a specially developed Dolby algorithm.