Wanted: iPhone Dolby Vision samples for testing

Musicvid wrote on 12/8/2021, 7:38 AM

Thanks to @misohoza for prompting me to write a LUT for his iPhone 11 / 12 footage. I need more actual MOV samples because there is a big need for a 709 transform, and no good LUT was ever written on the basis of one use-case, although he says my first attempt is working at 50% strength. (how's that for dumb luck?).

Anyway, these need to be actual pristine samples, not something that has been "corrected," and they need to be uploaded to Drive or Dropbox, not the forum or Youtube!

@vkmast has assured me that there are plenty of nearly-expired pizza coupons to go to the lucky respondents, so get shooting! One- or two-minute samples are best, outdoors and low light especially appreciated.

Comments

Former user wrote on 12/8/2021, 8:51 AM

@Musicvid Made a request to someone with a new iPhone mini, he's in the middle of electrical exams but i'll share what he comes up with when he shares 👍

Musicvid wrote on 12/8/2021, 8:57 AM

Thank you!

alifftudm95 wrote on 12/9/2021, 4:41 AM

I just bought iPhone 13, will share some footages from the phones for you.

Musicvid wrote on 12/9/2021, 9:02 AM

Thank you. Unbaking the Dolby Vision lemon cake is quite a challenge. The HLG luminance curve is pretty straightforward.

I'm noticing dynamic scene-by-scene color shifts with lighting variations, so a static one-size-fits-all LUT may be futile. But a daylight solution for the unnatural yellows may still be within reach.

alifftudm95 wrote on 12/11/2021, 3:57 AM

iPhone 13 clips

https://drive.google.com/file/d/1Tt7SRSSTs9C-V2PlBOfiin_uJVQah1oA/view?usp=sharing

HDR and Non-HDR

4K/HD @ 25fps

HEVC Codec

Yelandkeil wrote on 12/11/2021, 5:28 AM

Thanks for the sharing!

I'v always dreamed saying, hold your pocket tight please and someday buy an Handy with HDR...now I'm relaxed.

An Handy can't be a true camcorder no matter I-phone or U-phone 😁😁😁

(*Handy is a Denglish word for mobile phone.)

vkmast wrote on 12/11/2021, 7:30 AM

That's very handy 🙂.

Musicvid wrote on 12/11/2021, 12:08 PM

iPhone 13 clips

https://drive.google.com/file/d/1Tt7SRSSTs9C-V2PlBOfiin_uJVQah1oA/view?usp=sharing

HDR and Non-HDR

4K/HD @ 25fps

HEVC Codec

Got it, thanks! Will have fun with these.

Musicvid wrote on 12/11/2021, 9:00 PM

@alifftudm95 Those are very helpful, thanks!

Phil_P wrote on 12/12/2021, 1:18 AM

Hi @Musicvid great stuff. Do you still need more of these?

alifftudm95 wrote on 12/12/2021, 3:06 AM

How to properly edit an HDR video?

I understand ACES, the concept and purposes. But not HDR

when you enable HDR in VEGAS, its already in 32 bit full range and somewhat "ACES" already. (Kinda confusing for me)

How do you assign IDT for HDR clip? for an example iPhone 13? in the color space menu in VEGAS, you only have option for ARRI, Canon, Panasonic, Sony and some other normal color space like REC709/2020/sRGB etc.

Is that a reason why you crafting a LuT for iPhone?

Becuz working in HDR, I failed to get the iPhone clip to look "normal" or look 1:1 as I view it on my iPhone.

Yelandkeil wrote on 12/12/2021, 5:50 AM

Key point is the display specification - my experience: The computer (SDR or sRGB) monitor will not work really correct, though it's an alternative in the ACES menue.

1,
A normal HDR10 panel means it matches the Rec2020 space.
If you have a high-end screen, you can choose Rec2020 or P3-D65. Both are under Windows WCG definition.

2,
Go Windows system - Display Settings: Enable the HDR function. Try watching HDR10 video streams on Youtube. This is the final check for the NLEdit HDR environment.
From here, illustrations may not show correctly because they are captured from HDR10 sections.

3,
In VEGAS, set your project.
The View Transform follows your editing display specification, e.g. Rec2020 ST2084-1000nits, or P3D65 ST2084-108nits as above mentioned. -- The HDR view-button must be capable to switch on/off.
The source material is usually translated into its right colorspace by VEGAS. If not, do it manually.

4,
By rendering you have 3 choices:
HDR10, this is the very common format, for all purpose.
P3-D65, your client has such a display and wants this format.
HLG, a local TV-sender who requires porbably this format.

Yelandkeil wrote on 12/12/2021, 6:03 AM

PS: one day when you own an IDT equipment then begin studying that. The very moment just clean up "its already in 32 bit full range and somewhat "ACES" already." - where is the confusion?

A 32bit floating point environment is a virtual space for "precise" editing SDR videos; the output is Rec709 definition.

The ACESpace is borrowing that virtual environment as battlefield and open the special view transform for editing and outputing Rec2020HDR10 productions.

alifftudm95 wrote on 12/12/2021, 6:11 AM

My monitor is BenQ PD2700U, it advertise as "HDR monitor" with only 350 nit brightness.

The monitor offer sRGB, REC709, HDR, CAD/CAM, Animation, Low Blue Light, Darkroom and user Customization.

So does that mean in VEGAS, I need to pick a view transform with "1000 nits" or I somehow need to customize so that it fit "350 nits?"

My monitor: https://www.benq.com/en-my/monitor/designer/pd2700u/specifications.html

alifftudm95 wrote on 12/12/2021, 6:49 AM

I follow all your steps, seems working. But the preview on VEGAS vs Window player look diff:

Also, my YouTube videos still display bt709, I dont se bt2020. Something is wrong here.

And at the black part of the video, you can see giant Red box. (Maybe cuz its playing in 709, not HDR?)

Maybe need to restart my PC.

(Edited)

I resolve my issue why YT does not display HDR, cuz I turn off GPU Acceleration in Microsoft Edge

Yelandkeil wrote on 12/12/2021, 8:41 AM

Windows mediaplayer is very picky.

If I'm not mistaken, it won't play any HDR-video without proper format-head, e.g. my Samsung monitor has DP1.2 bandwidth, can only display HDR10 format - so, your clip looks also not "HDR" by me, because it's Dolby Vision.

Maybe, Dolby Vision needs bigger bandwidth.

But your Monitor - a very good one - has DP1.4 bandwidth, should occur no problem.
Or you're not using the correct cable?

Yelandkeil wrote on 12/12/2021, 8:47 AM

PS:

The Rec2020 ST2084-1000nits is a difinition, not meaning your panel must reach that brightness, just like many bad laptop-screens - perhaps can only cover 65% sRGB - but they are sRGB-monitors.

My Samsung U28R55x has only 300CD/m². but No doubt, it's a HDR10-monitor.

alifftudm95 wrote on 12/12/2021, 8:51 AM

@Yelandkeil I only use the monitor stock HDMI cable

Musicvid wrote on 12/12/2021, 10:03 AM

GENERIC HDR10 (2020 PQ ST2084) and GENERIC 2020 HLG are handled reasonably well in Vegas, and are really pretty straightforward, as long as the user is intimately familiar with Luminance considerations (both media and hardware) in high-bit domains.

[Redacted]

In the case of Dolby Vision®, a proprietary, licensed technology, which is what this inquiry was originally about, I have found that it employs dynamic XML metadata that cannot be addressed with a static custom LUT. The very best I can do is write custom, scene-specific transforms that may or may not work in other static-lit scenes, and absolutely will not work in shifting lighting conditions such as were encountered in this clip downloaded from Vimeo, for instance:

https://vimeo.com/471915502

However, I am still working on a generic, daylight-balanced LUT for Dolby Vision HLG -> REC 709, that "may" be useful in some static-lit situations. The exact comparisons provided by @alifftudm95 are most helpful in that respect, and to @Phil_P of course, the more sample data available, the better the end results.

[Redacted]

Peace and Prosperity.

vkmast wrote on 12/12/2021, 10:31 AM

@Musicvid re Dolby please see this comment from April 2021.

Musicvid wrote on 12/12/2021, 11:17 AM

That's too bad; I shall refrain from editorializing further. Back to my hibernaculum.

Musicvid wrote on 12/18/2021, 2:13 AM

There is not going to be a general purpose LUT for Dolby Vision. The dynamic XML stream metadata precludes that. LUTS are static.

A daylight-balanced LUT for Dolby Vision is still forthcoming, but it could only produce a truly stable, repeatable approximation in the studio, for reasons already covered. Correcting the HLG luminance curve is the easy part.

fr0sty wrote on 12/20/2021, 5:01 PM

Iphones lack the dynamic range to do even hdr10, why they waste money licensing 12 bit DolbyVision is beyond me.

Musicvid wrote on 12/20/2021, 6:52 PM

I believe the game is staying one step ahead of the Jones's. With the world aspin in HDR, I wonder if I'll ever see where it settles. Vanilla HDR10 PQ is a mystery to most people; Dolby Vision is a total albatross for the hobbyist editor, and for that reason I wonder if it will last.