Watching HDR10+ content on displays that don't support it?

[wonkey_monkey]

I'm thinking about buying a new TV but I'm struggling to find some decent technical info on HDR10, HDR10+, and DolbyVision.

One of the TVs I'm thinking about buying doesn't support HDR10+. If I tried to watch HDR10+ content on it, what would happen? Would HDR10+ content from a blu-ray, for example, just not play because the player wouldn't be able to "negotiate" HDR10+ with the TV? Or would the player convert it to HDR10 that looked more or less as intended?

If I got an HDR10+ file (assuming such a thing exists; I assume someone's come up with a way to put HDR10+ metadata in an MKV) and played it directly on the TV, would it be likely to just ignore the HDR10+ metadata, and would it therefore show scenes with the wrong brightness and contrast?

[gonca]

and played it directly on the TV, would it be likely to just ignore the HDR10+ metadata
yes
would it therefore show scenes with the wrong brightness and contrast
probably not, it would playback as hdr10
I assume someone's come up with a way to put HDR10+ metadata in an MKV
don't assume

All the devices (hardware/software player, AVR etc) would have to be HDR10+ capable

[FranceBB]

Yep, gonca is right, if your TV is HDR10 but not HDR10+ it won't benefit from the dynamically changing metadata and will basically play it back as normal HDR10 so H.265 10bit planar in PQ with static metadata. This isn't necessarily a bad thing as long as your TV has enough nits: in other words, if your TV has let's say 1000 nits and the contents is lower or equal to 1000 nits, you won't notice a thing. Trouble comes when the content you're trying to watch has more nits than your TV, like for instance science fiction stuff where everything is computer made and they pushed things up to a whopping 4000 nits (like in Blade Runner for instance). In that case, your poor TV will have to take the MaxCLL of 4000 nits and re-map it down to 1000 nits, thus adjusting everything else accordingly. If your TV had the chance to understand the dynamically changing metadata, however, it would adjust itself on a scene-by-scene basis rather than on a content-based basis, so it would do a far better job in remapping it down to its peak brightness.

Last but not least, on to Dolby Vision: if you were to play Dolby Vision, you always have 2 layers. The first one is a base layer and it's a "legacy" HDR10 layer, so UHD H.265 HDR PQ 10bit while the second layer is a metadata layer (which is seen as a fake 1920x1080 H.265 10bit HDR PQ layer which is completely green if you try to decode it alone as it's just made of metadata). If your TV understands Dolby Vision, it will use the base layer and the metadata layer to create a UHD HDR PQ 12bit with dynamically changing metadata, while if your TV doesn't understand Dolby Vision, it will completely ignore the second layer (the metadata layer) and just decode the "legacy" base layer as HDR 10.


p.s other than HDR10+ and Dolby Vision, make sure it reads HLG as literally all linear channels are broadcasted as BT2020 HLG and if it doesn't support it, it will be displayed as BT2020 SDR. Don't assume that all HDR10 TVs support HLG by default: HDR10, 10+, Dolby Vision all use PQ, so make sure the TV you're gonna purchase specifically supports HLG

[wonkey_monkey]

So it sounds like DolbyVision has better backwards compatibility if your TV doesn't support it, but it's also the better format if your TV does support it?

From what I've read it sounds like HDR10+ is currently losing to DV. Would you agree with that? All the TVs I've looked at support HLG.

[FranceBB]

So it sounds like DolbyVision has better backwards compatibility if your TV doesn't support it, but it's also the better format if your TV does support it?


Not necessarily better backwards compatibility, but it's definitely the better format as it's the only one to offer 12bit.



From what I've read it sounds like HDR10+ is currently losing to DV. Would you agree with that?


Although HDR10+ is probably more widespread, there's been an always increasing number of Dolby Vision UHD-BDs and other contents over the last few years and I expect that number to rise. Some of them were also shot in high frame rate at 59,940p which is amazing, but only a tiny minority.



All the TVs I've looked at support HLG.


nice, so you're gonna be fine with linear channels (Sky) and the BBC iPlayer too!
I'd strongly recommend "recent" David Attenborough's documentaries, they're something special in HLG!

[SeeMoreDigital]

From what I've read it sounds like HDR10+ is currently losing to DV..
You might be interested in the following: List of UHDs that contain Dolby Vision (https://forum.blu-ray.com/showthread.php?t=276448) and List of UHDs that contain HDR10+ (https://forum.blu-ray.com/showthread.php?t=300877)

Recently, Amazon Prime has started offering more and more Dolby Vision encoded content...

[Blue_MiSfit]

Yep, gonca is right, if your TV is HDR10 but not HDR10+ it won't benefit from the dynamically changing metadata and will basically play it back as normal HDR10 so H.265 10bit planar in PQ with static metadata. This isn't necessarily a bad thing as long as your TV has enough nits: in other words, if your TV has let's say 1000 nits and the contents is lower or equal to 1000 nits, you won't notice a thing. Trouble comes when the content you're trying to watch has more nits than your TV, like for instance science fiction stuff where everything is computer made and they pushed things up to a whopping 4000 nits (like in Blade Runner for instance). In that case, your poor TV will have to take the MaxCLL of 4000 nits and re-map it down to 1000 nits, thus adjusting everything else accordingly. If your TV had the chance to understand the dynamically changing metadata, however, it would adjust itself on a scene-by-scene basis rather than on a content-based basis, so it would do a far better job in remapping it down to its peak brightness.

Last but not least, on to Dolby Vision: if you were to play Dolby Vision, you always have 2 layers. The first one is a base layer and it's a "legacy" HDR10 layer, so UHD H.265 HDR PQ 10bit while the second layer is a metadata layer (which is seen as a fake 1920x1080 H.265 10bit HDR PQ layer which is completely green if you try to decode it alone as it's just made of metadata). If your TV understands Dolby Vision, it will use the base layer and the metadata layer to create a UHD HDR PQ 12bit with dynamically changing metadata, while if your TV doesn't understand Dolby Vision, it will completely ignore the second layer (the metadata layer) and just decode the "legacy" base layer as HDR 10.


This is only true for some flavors of Dolby Vision.

The most commonly used format for streaming is Profile 5, which is _not_ backwards compatible. It's full range ITP, dynamically shaped from 12+ bit RGB into 4:2:0 10 bit.

https://dolby.my.salesforce.com/sfc/p/#700000009YuG/a/4u000000l6G4/4R18riPaaW3gxpVx7XwyQLdEITLFjB.w.Si0LoQR5j8

Profile 7 (from UHD BluRay) is as you describe -- a HDR10 base with a secondary video stream aka enhancement layer plus metadata / RPU to reconstruct the signal in higher quality.

Profile 8.1 is just an HDR10 base with their special metadata / RPU (no enhancement layer)

Profile 8.4 is an HLG base with their special metadata / RPU.

The long-abandoned Profile 4 (which was the first widely used profile in the early days of HDR streaming e.g. Netflix / VUDU) was actually an SDR / BT. 709 base layer plus an enhancement layer and metadata / RPU to reconstruct the HDR (PQ + BT. 2020) presentation.

Profile 7 can theoretically offer the highest image quality, but in practice Profile 5 is the best quality.

[Balling]

So it sounds like DolbyVision has better backwards compatibility if your TV doesn't support it, but it's also the better format if your TV does support it?

From what I've read it sounds like HDR10+ is currently losing to DV. Would you agree with that? All the TVs I've looked at support HLG.

In fact Dolby Vision is only format that MAY HAVE NO backward compatibility with HDR10, if it uses IPTPQc2. Most of content in the wild. HDR10+ is losing. But Galaxy phones support HDR10+ only and in cameras... So there is that. iPhone is less of market segment.

"Profile 7 can theoretically offer the highest image quality, but in practice Profile 5 is the best quality."

The other way around. Blu-rays just win because of high bitrate. Even though IPTPQc2 is more efficient.

[Balling]

It is possible to approximate HDR10+ using Dolby Vision 3 segment curve. So, just need someone to come up with it.

[Blue_MiSfit]

In fact Dolby Vision is only format that MAY HAVE NO backward compatibility with HDR10, if it uses IPTPQc2. Most of content in the wild. HDR10+ is losing. But Galaxy phones support HDR10+ only and in cameras... So there is that. iPhone is less of market segment.

"Profile 7 can theoretically offer the highest image quality, but in practice Profile 5 is the best quality."

The other way around. Blu-rays just win because of high bitrate. Even though IPTPQc2 is more efficient.

My understanding was that Profile 7 + FEL would give the best possible reconstruction of 12 bit RGB PQ, but I have not tested this :)

Some UHD BD discs use Profile 5 of course (and it's _dramatically_ simpler in all regards) so maybe it's just flat-out better?

[SeeMoreDigital]

Some UHD BD discs use Profile 5 of course (and it's _dramatically_ simpler in all regards) so maybe it's just flat-out better?Interesting... Which movies? I would like to buy one for testing purposes...

[Balling]

Blu-ray does not support profile 5.

[Blue_MiSfit]

From what I was reading this is incorrect, and there have been some discs authored with Profile 5. I forget which, but there's been discussion on it somewhere here :)

[rwill]

From what I was reading this is incorrect, and there have been some discs authored with Profile 5. I forget which, but there's been discussion on it somewhere here :)

If its discussed on Doom9 it must be true. Profile 5 Blu-Rays would be news to me but I am here to learn. So, citation needed?

[Audionut]

Profile 5 uses the proprietary IPTPQc2, with no backwards compatibility, so I highly doubt it will make it to BD/UHD. I've not seen it.

Profile 7 contains 2 types of enhancement layer.

MEL, which is a Minimum Enhancement Layer, containing only metadata, and appearing a corrupt green. As far as I'm aware, this layer is always less than ~2500 kbps.
FEL, which is the Full Enhancement Layer, which apart from containing the metadata, appears grey, can either appear as entirely noise or provide a pixelated-greyscale video that resembles the base layer. These FEL layers are also always greater than ~2500 kbps. I'm almost certain I have seen this layer as high as ~8500 kbps, but cannot find the source with a quick search.

Everything Everywhere All at Once [2022]
MPEG-H HEVC Video 58997 kbps 2160p / 23.976 fps / 16:9 / Main 10 @ Level 5.1 @ High / 4:2:0 / 10 bits / 1000nits / HDR10 / BT.2020
* MPEG-H HEVC Video 7565 kbps (11.36%) 1080p / 23.976 fps / 16:9 / Main 10 @ Level 5.1 @ High / 4:2:0 / 10 bits / 1000nits / Dolby Vision FEL / BT.2020


Wikipedia says, "ICTCP has near constant luminance, which improves chroma subsampling versus YCBCR.[17] ICTCP also improves hue linearity compared with YCBCR, which helps with compression performance and color volume mapping.[18][19] When combined with adaptive reshaping ICTCP can improve compression performance by 10%."

Profile 7 FEL can contain a layer in excess of 11% of the overall bitrate. This layer can also include data that improves the underlying HDR10 baselayer (I'll hunt down a link that shows better grain retention and sharpness). So I do not accept that Profile 5 is the best quality, in practice.

edit: Also Profile 5 is 10 bits, and Profile 7 is up to 12 bits.

edit2:
Léon AKA Léon: The Professional [1994]
Video: MPEG-H HEVC Video / 55078 kbps / 2160p / 24 fps / 16:9 / Main 10 @ Level 5.1 @ High / 10 bits / HDR10 / BT.2020
* Video: MPEG-H HEVC Video / 13180 kbps / 1080p / 24 fps / 16:9 / Main 10 @ Level 5.1 @ High / 10 bits / Dolby Vision / BT.2020

Still hunting a comparison link.

[SeeMoreDigital]

These FEL layers are also always greater than ~2500 kbps. I'm almost certain I have seen this layer as high as ~8500 kbps, but cannot find the source with a quick search.

Cliffhanger is over 11,600Kbps. Death Wish (2018) is over 13,000Kbps. Dredd (2012) is around 14,000Kbps. Ghost in the Shell is nearly 15,000Kbps....

[Balling]

From what I was reading this is incorrect, and there have been some discs authored with Profile 5. I forget which, but there's been discussion on it somewhere here :)

Profile 7 is literally called Blu-ray profile. There is only it on Blu-ray.

[rwill]

I asked around among my colleagues and no one heard of Profile 5 on official UHD BDs. My somewhat recent BDA spec copy only seems to mention what appears to be Profile 7 too. So Profile 5 on BD is maybe Fake News! Disinformation on some Internet forum, well I never…

The EL can get up to around 20-25% rate of the BL, the combined rate of BL and EL must be below ~100 Mbit/s because of disc speed though. This becomes relevant if the BL is, for example, a 1k nits HDR10 grade and the full Dolby Vision is a 4k nits grade. In this case the enhancement layer must carry the difference between the 1k and 4k nits grade with minimal quality impairment.

As far as I know Profile 7 is supposed to be a more premium experience if compared to Profile 5. Reason being is that UHD BluRay is also supposed to be the go-to solution for semi-pro home cinema, like, these really expensive setups. ~15Mbit/s UHD Profile 5 can be delivered more flexible and most of the time requires less of an monetary investment from the consumer.

[wswartzendruber]

I'm thinking about buying a new TV but I'm struggling to find some decent technical info on HDR10, HDR10+, and DolbyVision.

One of the TVs I'm thinking about buying doesn't support HDR10+. If I tried to watch HDR10+ content on it, what would happen? Would HDR10+ content from a blu-ray, for example, just not play because the player wouldn't be able to "negotiate" HDR10+ with the TV? Or would the player convert it to HDR10 that looked more or less as intended?

If I got an HDR10+ file (assuming such a thing exists; I assume someone's come up with a way to put HDR10+ metadata in an MKV) and played it directly on the TV, would it be likely to just ignore the HDR10+ metadata, and would it therefore show scenes with the wrong brightness and contrast?
You're fundamentally viewing video in the Perceptual Quantizer format. Because PQ has such a wide dynamic range, no television currently exists on the market that can display that range. Because televisions are currently limited to a subset of PQ, metadata is used to map the (potentially) full dynamic range of PQ into the range your television can display.

HDR10

The most basic form of metadata. It contains two main values:

1. MaxCLL - The luminosity potential of the brightest pixel (measured in nits). This value is a lot more complicated than most people believe. Unless you want to know more, I will leave this explanation as-is.

2. MaxFALL - The overall luminosity of the brightest frame.

These two values are set for the entire presentation being watched. This may cause a scene that does not exceed your TVs dynamic range capabilities to be unnecessarily tone mapped.

HDR10+ / Dolby Vision

These metadata formats contain not only more information, but do so on a scene-by-scene basis, and, if necessary, on a frame-by-frame basis. This helps ensure that each specific scene is tone mapped for your television. Both formats contain fallback HDR10 metadata for sets that don't understand them.

A UHD Blu-ray movie, in practice, will always contain HDR10. It may optionally include HDR10+, Dolby Vision, or both. Including all three lets the television use the most capable one it supports. Although I will say that I see Dolby Vision winning over HDR10+.