Dolby Vision = ≠ vs HDR ?

[Geoff D]

Originally Posted by Adam4Rizzel

Here’s a question: Why would studios pay licensing fees to Dolby if HDR10 offered the same amenities? Why would there be a development of HDR10+ if HDR10 was superior? Dynamic metadata contains more metadata overall than static metadata.

Go get a roll of 24 or 36 exposure film and put it on the scanner. You can dial in one set of exposure settings, one set of color settings, and one set of contrast settings for the whole roll and scan every frame with the same settings or you can go in and individually fine tune each frame with its own settings. That’s the difference between HDR10 and Dolby Vision.

My bias is towards releases, on disc, with Dolby and HDR10+ presentations, when such film has been graded for that format. I wish they would include DV on this disc. The DV grade, on this disc, would be the definitive version.

Dolby Vision is not a grading system, it's a metadata system. The HDR content itself has been graded from shot to shot, scene to scene, just like any other piece of content which would be digitally graded. Once the grade is finalled it's fed into an automated system which analyses the image and creates the metadata, both static and dynamic. With DV they can manually adjust the metadata (unlike 10+) when looking at whatever trim pass e.g. 100-nit 709 SDR to ensure that the mapped version looks as it should, but this is NOT adjusting the grading of the finalled HDR master at source, merely how it's being interpreted by the metadata when set to a certain trim pass.

When it comes to how target displays interpret absolute luminance HDR content then yes, dynamic metadata is far more flexible than static but its importance is waning as more and more displays feature their own dynamic analysis of the image itself, not just relying on the static metadata numbers to apply an ill-suited tone map. If anything dynamic metadata is more important the further down the line you go in terms of the quality of the display's processing, as older premium sets and supermarket specials aren't always great at tone mapping so they need that guiding hand of dynamic metadata.

Dolby does have other advantages that still endear it to me no matter what display it's being viewed on, like FEL rebuilds of poorly compressed base layers, but even this system is not used by all when it comes to UHD disc and it is not used by streaming DV at all, where you're basically watching a 10-bit stream upsampled to 12-bit with dynamic metadata embedded.

[MovieGuy999]

Originally Posted by Geoff D

Dolby Vision is not a grading system, it's a metadata system. The HDR content itself has been graded from shot to shot, scene to scene, just like any other piece of content which would be digitally graded. Once the grade is finalled it's fed into an automated system which analyses the image and creates the metadata, both static and dynamic. With DV they can manually adjust the metadata (unlike 10+) when looking at whatever trim pass e.g. 100-nit 709 SDR to ensure that the mapped version looks as it should, but this is NOT adjusting the grading of the finalled HDR master at source, merely how it's being interpreted by the metadata when set to a certain trim pass.

The source is still being graded in Dolby Vision.

https://www.dolby.com/technologies/dolby-vision/

[gigan72]

Originally Posted by MovieGuy999

The source is still being graded in Dolby Vision.

https://www.dolby.com/technologies/dolby-vision/

If I recall correctly content 'graded in Dolby Vision' means it's graded in HD10 with a Dolby Vision layer added on top (or around) it all

[Geoff D]

Originally Posted by MovieGuy999

The source is still being graded in Dolby Vision.

https://www.dolby.com/technologies/dolby-vision/

Nah. Dolby Vision is not a grading system in itself, no matter what their PR might tell you. That’s the same site that says “generic HDR” is limited to 1000 nits which is an outrageous lie.

You grade content in the ST.2084 transfer function with D65 white point and P3 colour primaries using whatever software suite, then the metadata analysis is created from that and it’s this analysis that constitutes “Dolby Vision”.

[gkolb]

Originally Posted by Geoff D

Nah. Dolby Vision is not a grading system in itself, no matter what their PR might tell you. That’s the same site that says “generic HDR” is limited to 1000 nits which is an outrageous lie.

You grade content in the ST.2084 transfer function with D65 white point and P3 colour primaries using whatever software suite, then the metadata analysis is created from that and it’s this analysis that constitutes “Dolby Vision”.

And then the disc based HDR10 base layer is extracted from that, with the DV layer created in the split (might not be correct terminology?).

[Geoff D]

Originally Posted by gkolb

And then the disc based HDR10 base layer is extracted from that, with the DV layer created in the split (might not be correct terminology?).

They use the DV metadata to generate the HDR10, yes. This base layer (in its final compressed form) is compared to the uncompressed master and the resultant "difference data" is compressed into a 1920x1080 enhancement layer, along with the payload of dynamic metadata. That's only for FEL titles mind you as MEL ones (Sony, Warners) don't have the difference data, only the dynamic metadata, it's literally the HDR10 layer uprezzed into 12-bit for output.

[MovieGuy999]

Originally Posted by Geoff D

Nah. Dolby Vision is not a grading system in itself, no matter what their PR might tell you. That’s the same site that says “generic HDR” is limited to 1000 nits which is an outrageous lie.

You grade content in the ST.2084 transfer function with D65 white point and P3 colour primaries using whatever software suite, then the metadata analysis is created from that and it’s this analysis that constitutes “Dolby Vision”.

Which is called grading in Dolby Vision. If that analysis was never done, there would be no Dolby Vision Grade.

[Geoff D]

Originally Posted by MovieGuy999

Which is called grading in Dolby Vision. If that analysis was never done, there would be no Dolby Vision Grade.

You can call it what you like. Dolby Vision master, mezzanine, grade, whatever. But in terms of the HDR grading at source level, i.e. the final "look" of the HDR master itself, there is no such thing as Dolby Vision, just a set of industry standards* used for grading. You then run the analysis and fine tune the trim passes to create the metadata for whatever versions, but you're still not physically altering the master. For cinema EDR releases then you could call that "Dolby Vision" grading as it's designed for a specific 108-nit system exclusive to Dolby, but for the home the lines are blurred (figuratively, not literally ).

* though as Dolby themselves created the ST.2084 transfer function a.k.a. Perceptual Quantizer then is all PQ-graded content visioned by Dolby? Discuss.

[Scottishguy]

Geoff. Handing out technologically induced existential crises since who knows when.

[Chumley]

Originally Posted by Scottishguy

Geoff. Handing out technologically induced existential crises since who knows when.

February of 2009. It's right there under his name, duh.

[Scottishguy]

Originally Posted by Chumley

February of 2009. It's right there under his name, duh.

That's only on this board though

[Farerb]

Originally Posted by Scottishguy

That's only on this board though

Unless Geoff is 12 years old

[Chumley]

Originally Posted by Farerb

Unless Geoff is 12 years old

Geoff, much like Athena, was born fully formed, schooling fools right out of the gate.

[Scottishguy]

As for all HDR being visioned by Dolby. No. HDR has existed long before in photography before Dolby brought the tools for it to work in the home video space. That's my laymans understanding at least.

As for HDR 10+

https://www.youtube.com/watch?v=ag_x...ature=youtu.be

[Geoff D]

Originally Posted by Scottishguy

As for all HDR being visioned by Dolby. No. HDR has existed long before in photography before Dolby brought the tools for it to work in the home video space. That's my laymans understanding at least.

As for HDR 10+

https://www.youtube.com/watch?v=ag_x...ature=youtu.be

I don't mean HDR as a concept in itself, those multi-exposure shots have been a thing for years in photography as you say, and in VFX for movies where they captured the full range in stills for their background plates.

But in terms of the actual technology needed to bring it into the home environment then it's Dolby's baby, the ST.2084/PQ transfer function used in HDR10 and DV is literally their creation. Which is why I specifically said "all PQ-graded content".

[Scottishguy]

Originally Posted by Geoff D

I don't mean HDR as a concept in itself, those multi-exposure shots have been a thing for years in photography as you say, and in VFX for movies where they captured the full range in stills for their background plates.

But in terms of the actual technology needed to bring it into the home environment then it's Dolby's baby, the ST.2084/PQ transfer function used in HDR10 and DV is literally their creation. Which is why I specifically said "all PQ-graded content".

Well there wasn't exactly anyone else that was going to make it happen on a consumer level. It's still entirely separate from DV, which is a set of technologies and standards for HDR made by Dolby Labs.

[Geoff D]

Originally Posted by Scottishguy

Well there wasn't exactly anyone else that was going to make it happen on a consumer level. It's still entirely separate from DV, which is a set of technologies and standards for HDR made by Dolby Labs.

Who said it wasn't separate though? Again: as a concept 'HDR' has existed for years but I wasn't talking about its provenance as a concept, I was talking about its provenance as a specific piece of industry-ratified home video technology, of which ST.2084/PQ is *not* the same technology as what photographers were/are doing. When talking about it on this board and in reference to these subjects that home video inference will always be the primary context for me, just FYI, and was specifically referenced in that post anyway.

Or are you just on a wind-up mission now? In which case well played sir

[Scottishguy]

Originally Posted by Geoff D

Who said it wasn't separate though? Again: as a concept 'HDR' has existed for years but I wasn't talking about its provenance as a concept, I was talking about its provenance as a specific piece of industry-ratified home video technology, of which ST.2084/PQ is *not* the same technology as what photographers were/are doing. When talking about it on this board and in reference to these subjects that home video inference will always be the primary context for me, just FYI, and was specifically referenced in that post anyway.

Or are you just on a wind-up mission now? In which case well played sir

No mostly I'm just sitting here like I'm watching Star Trek TNG tecnobabble dumbfounded. Trying to innocently advance the conversation without shooting myself in the foot.

I don't recall saying it was used in photography, thar Dolby tec. Though I think on these boards people are still highly likely to make that great leap. Nothing, and I mean nothing with HDR is simple as I've learned, and continue to.

The problem is HDR on a surface level can seem simplistic. And the danger then is people do make leaps thinking because that seems simple enough, then this must be. Nopeeee.

[Geoff D]

Originally Posted by Scottishguy

No mostly I'm just sitting here like I'm watching Star Trek TNG tecnobabble dumbfounded. Trying to innocently advance the conversation without shooting myself in the foot.

I don't recall saying it was used in photography, thar Dolby tec. Though I think on these boards people are still highly likely to make that great leap. Nothing, and I mean nothing with HDR is simple as I've learned, and continue to.

The problem is HDR on a surface level can seem simplistic. And the danger then is people do make leaps thinking because that seems simple enough, then this must be. Nopeeee.

Nothing was said about using Dobly in photography, you're the one who brought up HDR as a concept that existed in photography when I didn't make that conflation to begin with and oh what's the ****ing point. Whatever dude.

[Scottishguy]

Originally Posted by Geoff D

Nothing was said about using Dobly in photography, you're the one who brought up HDR as a concept that existed in photography when I didn't make that conflation to begin with and oh what's the ****ing point. Whatever dude.

My point was maaaan. That the first thing before we discuss HDR home video being an entirely Dolby creation. That HDR has existed in the photographic world for a long time.

Because don't want people very well people thinking HDR as a whole is Dolby, do we dude?