Blackmagic Forum

I am using a Vizio P series to monitor the output of Resolve Studio 15.0b3 with an UltraStudio 4K Extreme. When my output color space is set to Rec.2100 HLG, my Vizio displays the color space as HDR-10. I'm on the most recent firmware on the Vizio and I have played test files such as LG Cymatic Jazz 4K Demo.ts or files I have transcoded to HEVC and the display shows they are playing as HLG. Does Resolve support outputting HLG metadata over HDMI yet? Is that something coming in the near future? Thanks!

I don't think UltraStudio 4K Extreme is updated to flag HDMI signal as HLG.
Ask BM support.

Reading this bug report right after this post is amusing to say the least, as it directly validates Martin's concerns.

This is bit different issue.
HLG is new, so not many devices support it. It can be added (as it's simply some metadata on HDMI signal) with update, but BM has to do it on UltraStudio+ Resolve side. I don't remember reading that HLG is now supported, so people should not expect it to work. It's just not implemented.

Andrew Kolakowski wrote:HLG is new, so not many devices support it. It can be added (as it's simply some metadata on HDMI signal) with update, but BM has to do it on UltraStudio+ Resolve side.

What metadata did you have in mind for HLG? I thought that HDMI 2.0a already supported the static info to indicate the source is HLG? Apart from that I do not think there is any other metadata required.

Yes, I'm talking about flag in HDMI, which tells TV that data is in HLG format.
It's in the spec, but if you implement it or not it's a different matter. Not all features are mandatory.
In this case it's even bit more complicated as "command" has to come from Resolve to BM device to flag signal as HLG.

HLG works just fine with the Decklink 4K mini, as long as you have the ability to explicitly set your monitor device to HLG. Consumer monitors likely will not do that as you cannot override the input signal.

The only thing annoying is if you set "Enable HDR metadata over HDMI' it sends HDR10 info over the HDMI even when your output color space gamma is a HLG variety. What it should do is look at the 'Output Color Space' and determine based on this what to send (if anything at all).

Cary Knoop wrote:HLG works just fine with the Decklink 4K mini, as long as you have the ability to explicitly set your monitor device to HLG. Consumer monitors likely will not do that as you cannot override the input signal.

The only thing annoying is if you set "Enable HDR metadata over HDMI' it sends HDR10 info over the HDMI even when your output color space gamma is a HLG variety. What it should do is look at the 'Output Color Space' and determine based on this what to send (if anything at all).

This is the point.
Most consumer TVs have no manual switch, so you are on mercy of auto flagging.

In terms of actual data- HLG or HDR10 is just a normal 10bit (or 12) data, so it will work even with older HDMI (if you have ability to manually set TV).