Screenshot Comparisons 4K

[JoeDeM]

Originally Posted by bruceames.

I have 5k monitor but it's not HDR (do they even make one?). But fortunately I can just check them out on the actual display since it has a built in browser. Obviously few people will do that though.

The latest 4k and 5k Imac's have about 480nits, and apple just enable 10bit color in El Capitan, so it should display a pretty good picture it also supports the following profiles

ACES CG Linear (Academy Color Encoding System AP1)
Display P3
Rec. ITU-R BT.2020-1
Rec. ITU-R BT.709-5
ROMM RGB: ISO 22028-2:2013
SMPTE RP 431-2-2007 DCI (P3)

I don't own one, so I wonder if any here does and can give it a try.

[42041]

I assume the iMacs' IPS screens have the relatively poor contrast ratios inherent to that tech, doesn't seem like they'd be well-suited for HDR.

[David M]

Just to really state the obvious here - and forgive me if it's so obvious it doesn't need to be said - but you realize the HDR screen grabs are going to look dull and washed out when viewed on a regular SDR screen, right?

[JoeDeM]

Originally Posted by 42041

I assume the iMacs' IPS screens have the relatively poor contrast ratios inherent to that tech, doesn't seem like they'd be well-suited for HDR.

Yes, it's an IPS display, so it will suffer in the lower end, the same as other 4k IPS screens sold to the public as HDR capable, but I was more interested in how the screen captures would look on it.

[42041]

Originally Posted by JoeDeM

Yes, it's an IPS display, so it will suffer in the lower end, the same as other 4k IPS screens sold to the public as HDR capable, but I was more interested in how the screen captures would look on it.

Don't they all have local dimming of some sort? I'm not very knowledgeable about the current TV offerings, but seems like HDR would be pretty useless on a global backlight LCD panel.

[Geoff D]

Originally Posted by David M

Just to really state the obvious here - and forgive me if it's so obvious it doesn't need to be said - but you realize the HDR screen grabs are going to look dull and washed out when viewed on a regular SDR screen, right?

But it has been said bro: https://forum.blu-ray.com/showthread...1#post12107281

[JoeDeM]

Originally Posted by 42041

Don't they all have local dimming of some sort? I'm not very knowledgeable about the current TV offerings, but seems like HDR would be pretty useless on a global backlight LCD panel.

Sony's 2016 XBR55x850D which is rated as an HDR screen has no local dimming, and is IPS display, so yes you are right it would be useless but it doesn't stop them from claiming that it's HDR.

[ray0414]

Originally Posted by David M

Just to really state the obvious here - and forgive me if it's so obvious it doesn't need to be said - but you realize the HDR screen grabs are going to look dull and washed out when viewed on a regular SDR screen, right?

Yep. But I have a js9500 and the grabs are still dull and washed out on my tv because there's no hdr metadata in the pictures that tell the monitor how to display the picture properly.

[JoeDeM]

Originally Posted by ray0414

Yep. But I have a js9500 and the grabs are still dull and washed out on my tv because there's no hdr metadata in the pictures that tell the monitor how to display the picture properly.

Well that answers that. I guess until someone figures out a way to grab a frame with the metadata, it's all pretty much useless.

[James Freeman]

@Deciazulado

It is a strange coincidence that when the HDR image Levels (RGB) are manipulated the color looks accurate or at least comparable to the bluray image.
What color space does Blu-Ray.com uses for these HDR screenshots?

Here is a comparison between Spiderman Blu-Ray color and "HDR to SDR" color:


As you can see the color space conversion is different.
The clowns hair (like the Flare in Mad Max) looks more red on SDR compared to HDR.
The levels/curves can be fixed so the HDR image looks similar to the SDR in terms of dynamic range, but the color conversion that the studios do to make the SDR image look more like the P3 one, is not that simple.

[pawel86ck]

http://screenshotcomparison.com/comparison/169593
James@ but I like how spider-man suit looks after this HDR-SDR conversion . That suit has refined red texture like in real life, while on the BD it looks washed out and soft in comparison

http://screenshotcomparison.com/comparison/169598
not exact frame, but also blue outfit looks more refined on HDR-SDR picture

[Geoff D]

Yikes, the highlights are badly clipped in each of those HDR-SDR pics though.

[Penton-Man]

Originally Posted by Oliver K

4k and HDR and 120 Hz? Sounds like Sony is in overkill mode for this one

Well following 4K spatial resolution finishing and the introduction and refinement of HDR, the next augmentation to next gen (UHD) video will be HFR

And on that note, at NAB to which I’m soon departing for, although not movie content and not primarily at the Sony booth, there will be an HFR demo over a realtime end-to-end chain over IPTV, which will be a first.

[puddy77]

Originally Posted by Penton-Man

And on that note, at NAB to which I’m soon departing for, although not movie content and not primarily at the Sony booth, there will be an HFR demo over a realtime end-to-end chain over IPTV, which will be a first.

Hey Penton,

While at NAB, are you going to SHED's Guardians of the Galaxy Vol.2 8k workflow presentation at the Red booth? I'd be interested in any info you'd wish to share.

http://www.studiodaily.com/2016/04/5...ow-kicks-butt/

[Arch Stanton]

Originally Posted by pawel86ck

http://screenshotcomparison.com/comparison/169593
James@ but I like how spider-man suit looks after this HDR-SDR conversion . That suit has refined red texture like in real life, while on the BD it looks washed out and soft in comparison

http://screenshotcomparison.com/comparison/169598
not exact frame, but also blue outfit looks more refined on HDR-SDR picture

HDR version looks awful tbh.

[pawel86ck]

Originally Posted by Geoff D

Yikes, the highlights are badly clipped in each of those HDR-SDR pics though.

Yes, but panasonic UHD player is supposed to deliver much better HDR-SDR converted picture, without so obvious clipping (at least that's what they wrote in panasonic UHD player review on trustedreviews)

[dvdmike]

Photoshop then

[Deciazulado]

Originally Posted by Geoff D

Yikes, the highlights are badly clipped in each of those HDR-SDR pics though.

...

Originally Posted by Deciazulado

If you're concerned bout the "clipping" for example you can dim down the highlights in player settings/modes till they'd don't clip (but look dimmer, so I guess you can then make the backlight of the TV britgher etc.) <snip> (if you put 100 nits = 100% then it'd be more clipping!)

Now some of the various modes in different players might have a massaged S curve<snip>

like I said before , you're concentrating on what a 10,000 to 0.0001 nit 10-bit image format converted (in 8 bits!) placeholder image looks like in 100 nit SDR 2.2γ computer image, most likely a ~1000:1 IPS LCD monitor. Like saying this Dolby Atmos multichannel mix sounds weird when heard in my stereo boom box.

[elwaylite]

Lmao!!!

[James Freeman]

Fellows could you be kind and try on your HDR TV these videos made from the HDR screenshots:
HDR Screenshot VIDEOS:

http://www.mediafire.com/download/w6...artian HDR.mp4
http://www.mediafire.com/download/16... of Pi HDR.mp4
http://www.mediafire.com/download/2p...Spider HDR.mp4
http://www.mediafire.com/download/94...Smurfs HDR.mp4
http://www.mediafire.com/download/57...h/Lego HDR.mp4
http://www.mediafire.com/download/2c...s Game HDR.mp4

Same method in reverse, SDR to HDR conversion (1080p, Rec.709, HDR).
Revenant HDR updated
Avatar HDR updated
Martian SDR to HDR Trailer.mp4
4K Sun HDR Test.mp4

Each one contains 5 screenshots from Blu-ray.com encoded with HEVC and contains HDR metadata that I created.
Each screen shot for 4 seconds on screen.
Roughly 10MB per screenshot HDR video.

*Copy to USB stick and play on TV or UHD Player.
Pause the video and use Next Frame to change screenshots.

The metadata is the same for all HDR videos (2160p, 1000nit peak, P3 inside 2020), just like Life of Pi and Exodus HDR clips we have seen.
My best guess is that the metadata of the UHD Blu Ray is the same therefor I chose to encode with these values....
It looks great with madVR.

Any comments are welcome.

Edit:

Revenant and Avatar have been updated so the average picture level matches the official UHD HDR blu-rays while the highlights still peak at 1000nit, the black levels were fixed too.
This is done with a reverse S-Curve, exactly the opposite of what they do to convert high dynamic (film or digital) to SDR-blu ray.

To find the right curve I converted the SDR martian photo to BT.2020 ST.2084 and then tweaked the curves to look exactly like the HDR photo, this gave me a reverse S-curve preset.
I just apply a "BT.2020 ST.2084.ICC" profile and my reverse S-Curve to the SDR image and get a straight SDR to HDR transfer.
Then encode these processed SDR to HDR photos to an HEVC video.