Which display for MadVR only?

[Blue_MiSfit]

HDR has been a bit of a scam if we really think about it. Didn't deliver on all the advertisement.


I disagree emphatically.

Well done HDR/WCG, particularly aggressively graded Dolby Vision content on OLEDs is absolutely amazing. It's a HUGE upgrade.

I completely fell in love with the look of it the second I saw it. Both the wide gamut and high dynamic range independently are fantastic.

That being said, HDR10 is more of a mixed bag. It can look great, but some studios produce separate HDR10 grades that are much more conservative / muted - to the point where SDR subjectively looks dramatically better to me.

HDR/WCG is a game changer that takes advantage of modern display characteristics. Freeing us from CRT derived gamma curves opens up a whole new world of creative possibilities.

That being said, I think there are some significant challenges outstanding. LCDs with local dimming are not ideal (even if they can get super bright), particularly when you enable subtitles. It drives me crazy to see a huge gray bloom in the letterbox surrounding a subtitle. It's super distracting. OLEDs are fine in this regard, but have their own issues - e.g. frame stutter as discussed prior, and sometimes smaller gamut.

Still, display tech is moving forward. SDR is great and all, but ultimately when you have a 1500 nit TV pushing a 100 nit SDR grade to the limit with the display in full thermonuclear store demo torch mode at some point you're going to run into issues. I think the mastering display tech and creatives have some catching up to do - this in conjunction with consumer panel improvements will make for some seriously awesome home theater experiences in a few years :)

[huhn]

no OLED is even close to HDR10 so sorry but 4000 nits is nothing we will see anytime soon and HDR10, HDR10+ and dolby vision are "mainly" container for the same image if it is in spec and an OLEd can't really do more then 700 nits and a peal of 1000 both are easily doable with all hdr specs.

[tp4tissue]

@ Blue_MiSfit,

You drank too much of that LG koolaid. hahaha

I recommend you read this article https://www.lightillusion.com/uhdtv.html.

They explain the basic principles behind the HDR Misinformation. Which has mainly been developed to sell people new TVs.

Dolby vision track is also fundamentally unnecessary and will be retired in the future, when we get REAL HDR displays instead of the FAKEDR ones we all own now..

[nevcairiel]

Which has mainly been developed to sell people new TVs.

Any technology they develop has the purpose of selling people new devices. I don't get the point you're trying to make. That doesn't mean it has to be bad. Good technology actually sells better.

The picture on a decent 1000nit+ HDR display can actually be rather good already - given properly mastered content. But there is no doubt the technology still has ways to go.

[huhn]

stuff like dolby vision (as used on a UBD) are still artificially. you could have done the same without it. so the better technology doesn't win if you can force more expensive ones that add nothing.

[tp4tissue]

So, dynamic metadata.

This is necessary when the grading monitor is significantly different from the final Consumer monitor when the grade is in an Absolute gamma curve

If the grade was done on HLG for example, then dynamic meta data is unnecessary.

The dynamic meta data is also Not precise on ALL displays, it itself is a half-way point between what the Director sees and what End Customer sees.


Overall, not a biggie, but When we have display parity, then we don't need dynamic meta data/ dolby vision , or even tone mapping.

This is why Moving forward, all that stuff will get retired.

[Blue_MiSfit]

@tp4tissue

Respectfully, the industry disagrees, and so do consumers. I've been doing this professionally for quite a long time, and work directly with the manufacturers, creatives, and software vendors on this issue. There's still disagreement on creative approaches, but everyone agrees HDR is a good thing, and everyone is making it.

Of course things aren't perfect - we indeed don't have consumer displays that are close to 4000 nits yet (tho I wish I had a water cooled Dolby Pulsar ;)), and display gamut is still too small in many cases, but this is improving.

Dolby Vision is not just PQ with dynamic metadata, there's a lot of stuff going on to adaptively shape the signal on a scene-by-scene basis from a high quality 4:4:4 12+ bit source into the intermediate 4:2:0 10 bit ICpCt intermediate space used for HEVC compression. Vision also goes deep into the display, making sure the full range 12 bit RGB signal can be properly reconstructed.

The dynamic metadata on top of that is a great way to grade content aggressively today, have it be presented reasonably on current HDR displays, and then (with no additional creative effort) be presented to the best possible effect on future HDR displays.

HDR10 is great, but has some issues. HDR10+ sounds cool, but not many TVs do it yet, and I haven't experimented with it. Vision brings even more to the table, and is widely supported. I see it as the best possible solution today. That may change.

HLG sounds great for live, but again there's not a lot of support out for it yet.

[huhn]

Dolby Vision is not just PQ with dynamic metadata, there's a lot of stuff going on to adaptively shape the signal on a scene-by-scene basis from a high quality 4:4:4 12+ bit source into the intermediate 4:2:0 10 bit ICpCt intermediate space used for HEVC compression. Vision also goes deep into the display, making sure the full range 12 bit RGB signal can be properly reconstructed.

the BD dolby vision spec doesn't do that. that's why i point at it. its an addional layer on top of the HDR10 stream and nothing else so you can't use ICpCt sub sampling which may help a little bit in compression. the "12 bit" if used like this isn't that convincing too if it comes from a 1080p support layer for highlights. TV have to measure the max brightness on each frame anyway to use ABL or APL more efficient so they kinda have dynamic meta data and HDR10+ provides it for FREE too.

THX certifies are on literally every low end speaker you can buy. i can buy a dolby vision HDR TV for 330 right now i'm not convinced that it will be any good in reproducing the signal even through they claim they have to do "whatever" to ensure quality but they have at least pay the "less then 3 USD per TV". even the free BBB movies is mastered from 16 BIT UHD images in 2008 a "a high quality 4:4:4 12+ bit source" is not impressing me in the slightest.

[chros]

Yep, that's correct, this is the LG way of doing things in the last 10 years at least. How hard would implement it in PC mode for only 24p content??? (Especially with 120Hz native displays.)
I was dead wrong about this, sorry everybody:
LG does support (https://forum.doom9.org/showthread.php?p=1871836#post1871836) 23p judder free playback in PC mode (meaning chroma 4:4:4)!

And about the HDR conversation (not WCG, not 10bit, etc, just HDR): I agree with the disbelievers. Just take a look what madvr can do with its tonemapping on 120 nits (and less, way less) displays! No ABL bullsh*t, no hardware limitations, no overused hardware components, etc.
So, my question is this: if it can / could be done in the world of SDR (using a PQ curve) then why would you need hardware that will never fullfil the max requirements? Only for sales purposes? :)

[nevcairiel]

The point of HDR screens is offering higher brightness and contrast for highlights. SDR screens cannot emulate this properly, since the SDR gamma curve doesn't really allow to do that - which is why we have the HDR PQ curve instead.
However, HDR content comes with some other improvements bundled up that you didn't get in SDR content, like wider colorspaces. Thats why tonemapping is required in the first place, because your screen cannot display BT.2020 or even DCI-P3, so something has to convert it to the colorspace of your TV - and madVR does a good job at that.

Unfortunately you cannot really enjoy the HDR highlights with current consumer display tech yet, since OLEDs lack max brightness, and LCDs lack proper backlight control. But there is always the future.

[huhn]

So, my question is this: if it can / could be done in the world of SDR (using a PQ curve) then why would you need hardware that will never fullfil the max requirements? Only for sales purposes? :)

120 nits and 500 nits look very different.
and the problem with tonemapping in general is you are going to miss the creators intend. the problem started with the need of meta data and nit number far from any sanity. even if we could create 10k nit screen putting them into every home is a very very bad idea...
just inform your self what a 1000 watt water cooker can do to the energy grid now add a TV show to that will show an image where the TV needs 1000 watt for about 5-10 sec. taking into account that the dolby vision screen is water cooled i'm very generous here and no there is a limited to power efficiency we are not going to make pure energy like light to use less energy.

i have no problem with PQ and using a bigger colorspace both make sense.

LG does support 23p judder free playback in PC mode (meaning chroma 4:4:4)!
you should test for 4:4:4.
http://madshi.net/madVR/ChromaRes.png

[Blue_MiSfit]

@huhn - you're absolutely right - Dolby Vision on UHD BluRay is quite different. I only care about Dolby Vision Profile 5 (non backwards compatible) since it's what's being used for VOD streaming these days, so my comments only apply to that flavor :)

[chros]

you should test for 4:4:4.
http://madshi.net/madVR/ChromaRes.png

Thanks, I did it before, my post (https://forum.doom9.org/showthread.php?p=1871836#post1871836) is updated.

i have no problem with PQ and using a bigger colorspace both make sense.

HDR content comes with some other improvements bundled up that you didn't get in SDR content, like wider colorspaces

But wider colorspace isn't HDR specific or am I wrong?

The point of HDR screens is offering higher brightness and contrast for highlights.
...
Unfortunately you cannot really enjoy the HDR highlights with current consumer display tech yet

the problem started with the need of meta data and nit number far from any sanity.

Exactly how I feel. What it means that tonemapping is always necessary on existing displays, and later when displays will be evolved the industry can easily master content with higher nits so new displays can be bought :)

even if we could create 10k nit screen putting them into every home is a very very bad idea...
just inform your self what a 1000 watt water cooker can do to the energy grid now add a TV show to that will show an image where the TV needs 1000 watt for about 5-10 sec.

That's exactly what I meant about hardware limitation.

the problem with tonemapping in general is you are going to miss the creators intend

Personally, I don't like this "excuse" (I already wrote about it a bit on avsforum): looking only at HDR10 (not DV and neither HDR10+), every display manufacturer does whatever they want to do, they even change their own approach in every new series of models, nothing is stone carved, mainly due to the above hardware limitations.

[nevcairiel]

But wider colorspace isn't HDR specific or am I wrong?


No its not, but for example UHD Blu-rays that use wide color and not HDR are actually relatively rare.

[huhn]

wait there is a spec for SDR on UBD?

[nevcairiel]

wait there is a spec for SDR on UBD?

There really are not many limitations. HDR is fully optional.

From the Blu-ray whitepaper:
https://i.imgur.com/Q4ll1uF.jpg

The only real limitation is that HEVC has to be 10-bit (8 is not allowed), and that BT.2020 has to use the new chroma sample location, while BT.709 uses the old one.

[huhn]

thanks the wiki is not well updated: https://en.wikipedia.org/wiki/Blu-ray#Video
and the UBD wiki doesn't have a video part at all.
is there a read about the chroma sub sample position?
that doesn't help me: For ITU-R BT.2020 (colour primaries is set to 9), chroma_loc_info_present_flag shall be set to 1 and
chroma_sample_loc_type_top_field and chroma_sample_loc_type_bottom_field shall be set to 2.

[nevcairiel]

Conceptually the Chroma stuff is not that complicated.

The image is a bit poor, but it shows it anyhow:
https://www.researchgate.net/profile/Jill_Boyce2/publication/327253648/figure/fig1/AS:664343440011264@1535403227082/Figure-E2-Location-of-the-top-left-chroma-sample-when-chroma-format-idc-is-equal-to-1.png

The black dots are Luma, and the Red one is the Chroma sampling location, plus the square to indicate the "area" the subsampled chroma sample covers. Typical 4:2:0 is type 0, "old" mpeg1 is type 1, and UHD now uses Type 2.

I don't know of a good simple article that explains the advantages between them really. Using the TopLeft location may be simpler to interpolate, or something.

[huhn]

thanks i know about mpeg1 and mpeg2 chroma subsample position i used this for illustration in the past: http://www.mir.com/DMG/chroma.html
so pretty much the same as SMPTE DV-PAL without interlancing.
only one last thing to ask about this do lav filter and madVR honour this and are able to handle this correctly?

[nevcairiel]

LAV will send that info to madVR, anything else is at least out of my hands.

[tp4tissue]

LAV will send that info to madVR, anything else is at least out of my hands.

should we always leave lav on 0-255, could you explain what are the cases where 16-235 is absolutely necessary.

[tp4tissue]

Even if we could create 10k nit screen putting them into every home is a very very bad idea...
just inform your self what a 1000 watt water cooker can do to the energy grid now add a TV show to that will show an image where the TV needs 1000 watt for about 5-10 sec.


Technologies co-evolve. If we didn't increase the number of electronics, we wouldn't have built a bigger grid, if we didn't build a bigger grid, we wouldn't use ever more electronics.

It's not as if Overnight, everyone will be running Kilowatt Tvs. They're a great idea, how will we engineer, to make that happen. Solar/Wind/Nook

[huhn]

should we always leave lav on 0-255, could you explain what are the cases where 16-235 is absolutely necessary.

it doesn't do anything with madVR... you could read the option to know what it's going todo.

Technologies co-evolve. If we didn't increase the number of electronics, we wouldn't have built a bigger grid, if we didn't build a bigger grid, we wouldn't use ever more electronics.

It's not as if Overnight, everyone will be running Kilowatt Tvs. They're a great idea, how will we engineer, to make that happen. Solar/Wind/Nook

don't tell anyone but the EU is heavily pushing household to lower there power consumption. hell there is maybe already a law that makes sure Tv can't be selled that can use that much power.

and yes the power grid is just increased so people can run use TV that use 10 times the power not for more people.

[markanini]

For a desktop form factor display models using the 1500:1 CR Panasonic IPS panel https://linustechtips.com/topic/981595-looking-for-a-high-contrast-ips-panel/