Hi,
This is not really important, I’m just curious….
On my Sky Q box, when my LG OLED TV detects HLG video, it flashes up a “HLG HDR” icon briefly in the corner of the screen.
However, when I play HLG video in Infuse, the TV displays just “HDR”.
Why is this? Is this because Infuse isn’t passing some crucial metadata to the TV? Is this something that Infuse could do?
As I say, not really important, and the HLG HDR video plays perfectly fine anyway.
Thanks for your help
Liz
This thread may answer your question.
There’s 2 comments in that thread that sound slightly contradictory to me (both from James)
I have the 2021 model.
I assume what we’re saying here is that the older Apple TVs don’t support HLG at all, and with the later Apple TVs HLG is being converted to HDR10? (either by Infuse, or the Apple TV itself?)
Thanks
Liz
correct.
HLG is an “over the air” broadcast TV format of HDR,
ATV doesn’t support HLG as there is no legitimate content that would be available for it to play, therefore no support is required.
the report of the appletv “supporting” it simply means that it won’t ignore it but send it as an HDR10 signal.
Cool, thanks. That’s all I wanted to know.
I would however disagree about legitimacy.
BBC iPlayer streams HLG HDR for all its programs, TV series etc., so HLG is a perfectly valid format. It may just not be as common as other HDR formats, but it is completely valid to use it for HDR streaming just like the other HDR formats. There’s no reason why the BBC iPlayer app on Apple TV for example couldn’t output HLG without conversion in principle, if Apple chose to support it in the future.
Hopefully that will happen at some point, as converting HLG HDR to HDR10 is not an ideal solution, and you will lose some quality doing that, due to the differences in how these HDR types work. Unlike Dolby Vision, HLG doesn’t have a HDR10 base layer, so real comversion is required to output HLG as HDR10.
Thanks
Liz
BBC don’t offer 4K/UHD let alone HDR content via iplayer on ATV though.
there’s a whole story about why that’s the case, but it’s more than just HLG support (or the lack of). it’s the same reason why there is no subtitle support in iplayer on ATV.
Yep,
Unfortunately, the AppleTV isn’t the most popular streaming device, and the apps are often compromised it seems to me, not meeting the capabilities of the device.
Another example is the Prime Video app. Sports should be 50fps, but on the Apple TV it looks like they play at 25fps, so look jerky, and poor.
This problem doesn’t happen on the Sky version of the Prime Video app, and everything looks super-smooth and perfect.
The only apps I actually use on my Apple TV are the Apple TV app itself (which obviously works perfectly) and Infuse, which I am more than happy with.
Pretty much every other app I use the Sky Q version (iPlayer is 4K and HLG of course too.)
It’s a shame, but that’s the way it is.
Liz
not quite true, and is certainly not the reason for the iplayer limited function
that’s just Amazon doing what Amazon do, and the issues there are squarely at the fault of Amazon. the cynic might suggest they purposely do that because the ATV is a competitor to their fire devices.
all other streaming apps work as they should, Disney, Netflix etc
your Sky Q box is fixed at 50fps for broadcast and 60fps for streaming content (if you have judder reduction enabled) - that’s all it can do. so you’re not actually getting any sort of frame rate matching on the Sky Q box.
to go a bit deeper into the iplayer issue, if you’re interested.
the reason is that BBC (and pretty much nobody else) use DVB-DASH to serve their UHD content (and to serve subtitles). BBC hitched their wagaon to that quite some time ago.
Apple don’t support DVB_DASH, and really have no need to as it’s meant solely for OTA broadcast.
so we have a situation where both Apple and BBC are in the right and in the wrong equally.
we shouldn’t expect BBC (publically funded) to spend money creating a version that works on the ATV (a niche device), but we also shouldn’t expect Apple to add support something that is used by just 1 app in a fairly small country in terms of device coverage.
the mistake BBC made was going with DVB-DASH, but that decision was made a long time ago.