I Have Published a HDR10 to HLG Converter

[FranceBB]

Originally Posted by SeeMoreDigital

I don't think the 'professional' end of the market was the spec wswartzendruber was originally aiming for...

Sure, but those are just samples, it doesn't really matter how I deliver them. Why would I change a BAT that I know works for something that I have to create from scratch?
I'm at work, I don't have any consumer BAT files, I encoded what was more convenient for me eheheheh

Originally Posted by wswartzendruber

What these test clips are encoded as is irrelevent so long as they convey the information correctly and thread participants can see them. These aren't meant for viewing, but for study with dedicated equipment.

Exactly.

[SeeMoreDigital]

Thanks guys,

Needless to say, I'd be most interested in seeing some of 'before' (HEVC HDR10) and 'after' (HEVC HDR10 HLG) HEVC encoded samples, to see how well my TV and OPPO handles them

[FranceBB]

Originally Posted by SeeMoreDigital

Thanks guys,

Needless to say, I'd be most interested in seeing some of 'before' (HEVC HDR10) and 'after' (HEVC HDR10 HLG) HEVC encoded samples, to see how well my TV and OPPO handles them

Fine.
I'm a consumer myself, by the way, regardless of my job I watch TV series too, so my library is made of consumer BD eheheheh
I can share a sample, I should have something somewhere, but it's gonna be short. Perhaps Gemini Man could be a good fit. I'll do that tomorrow, though, right now I'm at dinner and later I'm gonna watch Brighton Vs Chelsea

[wswartzendruber]

Originally Posted by SeeMoreDigital

Thanks guys,

Needless to say, I'd be most interested in seeing some of 'before' (HEVC HDR10) and 'after' (HEVC HDR10 HLG) HEVC encoded samples, to see how well my TV and OPPO handles them

Here are some HDR10 demos that I've converted to HLG:

http://wswartzendruber.net/videos/

EDIT: What is "HDR10 HLG?"

[FranceBB]

Originally Posted by wswartzendruber

EDIT: What is "HDR10 HLG?"

Nothing, he probably means H.265 10bit HLG eheheheh

[frank]

The LG TV displays the HLG HDR logo for 5 seconds at the top right when you play an HLG video.

[ErazorTT]

There is something that I still cannot wrap my head around. The PQ standard is very obvious and strict in that it's actualy a standard of absolute luminosity. Why do the movies then need such a wide range of lum-scale to equalize them?

[wswartzendruber]

Originally Posted by ErazorTT

There is something that I still cannot wrap my head around. The PQ standard is very obvious and strict in that it's actualy a standard of absolute luminosity. Why do the movies then need such a wide range of lum-scale to equalize them?

SMPTE says reference white goes at 100 nits. The ITU says that value should be 203 nits.

Alita: Battle Angel puts it around 47 nits (the darkest I've encountered). Shazam's is something stupid like 500+ (the brightest I've encountered).

I have no idea why studios are all over the place with it.

EDIT: I've noticed something somewhat common. Once you adjust the luminosity, the internal MaxCLL value ends up being very close to 1,000 nits. Sometimes I wonder if these movies aren't graded to 1,000 nits with reference white at 203 nits, and then scaled down so that TVs that can't reach 1,000 nits can still display more of the originally intended changes in brightness.

EDIT: And I was wrong about Shazam. It's reference white level is only 369 nits or thereabouts.

[ErazorTT]

Originally Posted by wswartzendruber

EDIT: I've noticed something somewhat common. Once you adjust the luminosity, the internal MaxCLL value ends up being very close to 1,000 nits. Sometimes I wonder if these movies aren't graded to 1,000 nits with reference white at 203 nits, and then scaled down so that TVs that can't reach 1,000 nits can still display more of the originally intended changes in brightness.

How do I get a hold on the internal MaxCLL?

[wswartzendruber]

(internal MaxCLL) = --max-cll * --lum-scale

or

(internal MaxCLL) = --max-cll * (203 / --ref-white)

It's not something you really need to take into consideration, however. pq2hlg determines this value for you. If it exceeds 1,000 nits, then pq2hlg will generate a tone map curve specific to the internal MaxCLL value.

[FranceBB]

Little update: I'll delay the encode and share of a real life sample a bit 'cause FFMpeg 5.0 introduced IMF decoding and it's something I've been waiting since April 2016 (when no one really knew anything about it and there was no way to work with it) so I'm as happy as Larry

[frank]

Alita has 5 different cll metadata:
LIGHT 285 63
LIGHT 737 130
LIGHT 1000 18
LIGHT 257 1
LIGHT 505 13

The core movie at 737 130.
Includes HDR10, DoVi, and HDR10+
That is the culprit. Someone played with parameters without changing the content.

The mastering display has 1000 nit / 0.0001 nit.
So stay on the standard with the PQ_to_HLG matrix (1000nit), and you will get a perfect HLG conversion.
Testet on LG OLED48CX.

[frank]

Content light metadata are only used if the display has not the desired luminosity. HDR10 strictly follows smpte2084. The TV scales itself brightness and contrast.
HLG arib-std-b67 is based on max 1000nit. The TV knows that and scales brightness automatically without HDR metadata.
repeat-headers for HLG is not necessary.

[wswartzendruber]

Originally Posted by frank

Alita has 5 different cll metadata:
LIGHT 285 63
LIGHT 737 130
LIGHT 1000 18
LIGHT 257 1
LIGHT 505 13

The core movie at 737 130.
Includes HDR10, DoVi, and HDR10+
That is the culprit. Someone played with parameters without changing the content.

The mastering display has 1000 nit / 0.0001 nit.
So stay on the standard with the PQ_to_HLG matrix (1000nit), and you will get a perfect HLG conversion.
Testet on LG OLED48CX.

That produces a result that is extremely dark when viewed on SDR.

[frank]

Oh, I still have to test on SDR...

[wswartzendruber]

Originally Posted by frank

Oh, I still have to test on SDR...

pq2hlg -m 737 -l 4.75 -s 65 pq2hlg-alita.cube

[frank]

Thanks.
I tested -m 1000 -r173
because of 130 x 4/3 = 173
Is better but I am not satified.

Let's go with your findings.

[frank]

Please change back the status lines like

# Generated by PQ2HLG 0.4.0
# ref-white: 203
# max-cll: 1000
...

in pq2hlg.
It is better for later doc of the cube.

[wswartzendruber]

Originally Posted by frank

Please change back the status lines like

# Generated by PQ2HLG 0.4.0
# ref-white: 203
# max-cll: 1000
...

in pq2hlg.
It is better for later doc of the cube.

Fresh out of the oven: PQ2HLG 0.4.1

[frank]

Thank you!

On my Alita tests I saw a big issue. VLC and mpv have different display outputs. mpv goes much earlier into level saturation!
I only can go until -l 2.5...3.0 for HLG. Otherwise you will be dazzled by white.

Which prog does it right? Different specs? max cll 100 vs 203?

I'll make further tests with the built-in player of LG TV.


--------------
System: Win 10 Pro on Dell XPS 15 9510