chros wrote: ↑Tue Oct 12, 2021 9:43 am
Thanks, my question is what the effect of min_pq value is in reality.
I don't really know but Dolby clearly says that min 0 for all the scenes is incorrect.
When I get home, I'll do the analysis with the HDR10plus algorithm and see if I get a different min pq for that clip.
chros wrote: ↑Tue Oct 12, 2021 9:43 am
It's Amazon hdr10+. Thanks for the test, measurement results are pretty close indeed (apart from the first avg value, where it's double), really interesting:
1- Resolve L6 maxCLL is set to 1680, but it measure more than 3000 nits? what's the unit of the values on the image, nits or PQ?
- - interestingly that's the measurement summary from madvr: MaxCLL 100%: 1680, 99.9%: 1545, MaxFALL: 58, AvgFALL: 9, AvgFMLL: 524 nits
2- Resolve set some L2 trim properties (that obviously dovi_tool doesn't by default), why is that? Did you set it or is it automatic?
3- Resolve has 3 blocks of L2 metadata, why is that? (target_max_pq: 2081, 2851, 3079; dovi_tool has just 1: 3079) Which one is used during playback?
Thanks, my question is what the effect of min_pq value is in reality.
1- the L6 metadata is edited manually, I just took the numbers from your post:
viewtopic.php?p=113519#p113519
2- this is the resolve default trim passes adjustments for each target display. You need a license to modify them in resolve but everything else is available and free to use.
3- As Quietvoid said.
For the foreseeable future, the current consumer display landscape encompasses a wide variety of
differently performing televisions and projectors that are guaranteed to improve year over year. This
means that mastering for today’s displays may render content less vibrant than content that emerges
five years from now. This can be especially vexing for narrative content that will have a long lifespan
on streaming services as new generations of viewers discover them. While one way of solving this
would be to re-grade your program many times at a variety of nit levels to create deliverables suitable
to a range of display capabilities, that’s an enormous amount of work.
Dolby Vision offers a shortcut by using sophisticated algorithms to derive automatically analyzed
metadata that intelligently guides how an image graded at one nit level (say 4000 nits) can be
adjusted to be perceptually similar to viewers watching a 1000 nit display. Highlights and saturation
that are too bright for a particular display will be adjusted to provide as close to the same experience
without clipping or flattening image detail.
Furthermore, this automatic analysis can be manually trimmed by a colorist to account for the artistic
intentions of the authors of a program, in cases where the automatic analysis doesn’t do exactly what’s
wanted. This combination of auto-analysis and manual trimming is key to how Dolby Vision streamlines
the process of mastering programs to accommodate backward compatibility with SDR displays, as well
as the varying peak luminance capabilities of different makes and models of HDR consumer displays,
both now and in the future. You’re only required to make a 100 nit trim pass to guide the HDR
program’s conversion all the way down to SDR, and the Dolby Vision system can use that information
to guide how intermediate presentations (such as at 700 or 1200 nits) should be adjusted. You can
even do multiple trim passes at specific nit levels, such as a 100 nit pass and a 1000 nit pass, to give
the Dolby Vision system more information to accurately guide intermediate presentations on different
displays. Additionally, you don’t have to trim every clip. If the analysis is good, you can skip those clips
and only trim clips that need it. The overall system has been created to make it as efficient as possible
for colorists to ensure that the widest variety of viewers see the image as it’s meant to be seen.
This, in a nutshell, is the advantage of the Dolby Vision system. You can grade a program on a more
future-proofed 4000 nit display, and use auto-analysis plus one or two manual trim passes to make the
program backward compatible with SDR televisions, and capable of intelligently scaling the HDR
highlights to provide the best representation of the mastered image for whatever peak luminance and
color volume a particular television is capable of. All of this is guided by decisions made by the colorist
during the grade.
At the time of this writing, all seven major Hollywood studios are mastering in Dolby Vision for cinema.
Studios that have pledged support to master content in Dolby Vision for home distribution include
Universal, Warner Brothers, Sony Pictures, and MGM. Content providers that have agreed to distribute
streaming Dolby Vision content include Netflix, Vudu, and Amazon. If you want to watch Dolby Vision
content on television at home, consumer television manufacturers LG, TCL, Vizio, HiSense, Sony,
Toshiba, and Bang & Olfusen have all shipped models with Dolby Vision supports
)