Screenshot Comparisons 4K - Page 36 - Blu-ray Forum

whitestang06 · 05-13-2018, 04:04 AM

Quote:

Originally Posted by Geoff D

I really am no expert on this so I don't have a clue as to what actual parameters or settings in HEVC would cause such a thing, but perhaps someone came up with a bitrate 'cheat' to keep luminance perfectly preserved but which badly hacks up the chroma channels even more, figuring that the awful chroma blocking would be mistaken for grain anyway? Whatever the case may be, it's extremely disconcerting.

I don't know what the studio encoders, namely that ATEME Titan one, have in terms of parameters, but X265 has various features like adaptive quantization and chroma QP offsets that could have an effect. What it looks like, to me, is that they push the limits of the information that can be contained within 4:2:0, particularly that 0, and the encoder simply runs out of allotted bits to try and contain it. Both Blade Runner and SPR are quite skimpy on the bitrate, given the raw complexity of the image. SPR may be at about the size limit, already, but it might also have better chroma info in the Dolby Vision extension. Blade Runner probably just needed an extra 20mbps, or so.

andreasy969 · 05-13-2018, 07:46 AM

EDIT: obsolete - all BD caps have been fixed

I went back to "Knowing" this morning to see how bad the gimp Problem really is and it's worse than I thought ...

I just redid the title shot and one of the "relevant" caps (the improvement is still there), but I'm afraid I'll "have to" revisit the BD caps of Knowing, The Post and Blade Runner. Even if no one else cares, I'm afraid that I do - just can't leave it like that ... Might do Knowing and The Post this evening and Blade Runner maybe tomorrow.

Anyway, here are the two I just redid to check how bad it really is:

previous UHD-BD cap, BD cap properly upscaled, original BD cap, previously effed up BD upscale (gimp 2.10):

As you can see, gimp 2.10 cubic scaling currently adds some serious blurring to the image ...

Damn. Damn. Damn.

Maybe sth similar happened at Universal with Oblivion. But like my grandma used to say: Only if you don't do anything, you will make no mistakes.

benhoppel · 05-13-2018, 08:15 AM

Quote:

Originally Posted by sentinel-fine

Cubic filtering? Wouldn't nearest neighbor be closest to the source?

Incorrect for upscaling. The samples stand for an analogue signal that needs to be recreated. NN does not do that properly.

Geoff D · 05-13-2018, 10:43 AM

Quote:

Originally Posted by whitestang06

I don't know what the studio encoders, namely that ATEME Titan one, have in terms of parameters, but X265 has various features like adaptive quantization and chroma QP offsets that could have an effect. What it looks like, to me, is that they push the limits of the information that can be contained within 4:2:0, particularly that 0, and the encoder simply runs out of allotted bits to try and contain it. Both Blade Runner and SPR are quite skimpy on the bitrate, given the raw complexity of the image. SPR may be at about the size limit, already, but it might also have better chroma info in the Dolby Vision extension. Blade Runner probably just needed an extra 20mbps, or so.

Yes, it's like they're robbing Peter to pay Paul when it comes to the bitrate allocation. As Pyoko said above, there's surely a middle ground here between taking a bit more from the luminance and giving it over to the chroma. It's almost like they're using adaptive parameters that are set to deliver the best results with cleaner low-noise sources, but when these same parameters are exposed to such intensely grainy sources like SPR they're giving over far too much bitrate to the temporal noise and leaving the chroma to fend for itself. Whatever encoder they're using it needs more fine tuning for sure IMO.

I appreciate what you're saying about these things possibly hitting the wall in terms of available space, Blade Runner especially as that should NEVER have been on a BD66, and SPR is a very long full-screen (no black bars) movie on a BD100, but Sony were producing decent-enough encodes that remain amongst the grainiest on the format on BD66 a full two years ago without these kinds of dreadful chroma artefacts. Their stuff is still free of this phenom AFAIK so whatever encoding parameters they're using I wish they'd share them with Paramount.

[edit] And if this is HEVC straight up running out of steam then I'd gladly trade a bit of coherence in the luminance to give the chroma more room to groove, I'd rather have a tickle of conventional blocking than these shite chroma artefacts which also robs the chroma channels of whatever resolution they've got left.

benhoppel · 05-13-2018, 11:02 AM

Quote:

Originally Posted by sentinel-fine

BTW, nearest neighbor is actually how digital photography originally acquires a picture from the real world and I wish standalone players gave the user the option to have that.

Point sampling is not a scaling algorithm. You are confusing concepts.

Pyoko · 05-13-2018, 03:07 PM

Often noticeably sharper/more detailed with better grain. Except perhaps for the VFX, the UHD master was most likely upscaled directly from 2.8K.

BD left, UHD right

andreasy969 · 05-13-2018, 03:50 PM

I fixed the blurred BD upscales of all 3 now - 'Knowing' catches up a little bit again now and at the same time has its sharpening back, 'The Post' has its grain back and 'Blade Runner' regains its dignity. You may want to compare all 3 again.

Sorry for the little screw-up.

chip75 · 05-13-2018, 04:00 PM

Quote:

Originally Posted by andreasy969

I fixed the blurred BD upscales of all 3 now - 'Knowing' catches up a little bit again now and at the same time has its sharpening back, 'The Post' has its grain back and 'Blade Runner' regains its dignity. You may want to compare all 3 again.

Sorry for the little screw-up.

No worries, I think everyone knows mistakes happen at times, and the odd glitch is outweighed by your hardwork and regular contributions.

Pyoko · 05-13-2018, 05:35 PM

"2K DI"

Yeah I'm going to have to call bullshit on that one...

Granted the BD isn't great and seems prone to aliasing, but that ain't to 2K grain on the UHD. I guess IMDb etc. are conflating the intermediate/working resolution with the final DCP resolution (as information on the former isn't as readily available.)

BD left, UHD right

TheSweetieMan · 05-13-2018, 06:39 PM

'La La Land' is a terrific looking UHD disc.

Pyoko · 05-13-2018, 06:41 PM

It would be clearer if the sentence at the end read "the mastering resolution was 2K for digital cinema." That's just the very final output though and just one of the masters. Other possible masters are SD, HD, UHD, broadcast, digital download etc. with various resolutions and specifications.

It doesn't mean the first thing they did after scanning was to downscale it to 2K and then work from that, that would be the intermediate resolution, but I guess the terminology has gotten all muddled since the term DI started being applied to everything and not just the original film workflow. The UHD is definitely no upscale from 2K.

Geoff D · 05-13-2018, 08:11 PM

LLL is a quite lovely UHD disc. RE: the caps, any signs of the extreme banding in darker shots that people were reporting before?

Geoff D · 05-13-2018, 08:28 PM

Quote:

Originally Posted by andreasy969

I fixed the blurred BD upscales of all 3 now - 'Knowing' catches up a little bit again now and at the same time has its sharpening back, 'The Post' has its grain back and 'Blade Runner' regains its dignity. You may want to compare all 3 again.

Sorry for the little screw-up.

All three still smack the Blu-ray silly. I dunno what's worse with The Post's BD, the overly soft gimped look (see what I did there?) from before or the ungimped look because the BD's "grain" looks awfully like macroblocking to me, I've not been impressed with Fox's 1080p encodes lately and this looks like another example...providing there aren't any more issues with the BD caps.

Pyoko · 05-13-2018, 09:47 PM

Quote:

Originally Posted by Geoff D

LLL is a quite lovely UHD disc. RE: the caps, any signs of the extreme banding in darker shots that people were reporting before?

Haven't watched the disc so I don't know how widespread it is but it seems to only appear in specific instances, and it's basically huge swathes of slow-moving blocking in the near-blacks. It's extremely bad in this shot, but it's really difficult to make out when converted to SDR so it might just be another freak OLED HDR tone-mapping issue:

Spartan21 · 05-14-2018, 03:52 AM

Quote:

Originally Posted by andreasy969

EDIT: obsolete - all BD caps have been fixed

I went back to "Knowing" this morning to see how bad the gimp Problem really is and it's worse than I thought ...

I just redid the title shot and one of the "relevant" caps (the improvement is still there), but I'm afraid I'll "have to" revisit the BD caps of Knowing, The Post and Blade Runner. Even if no one else cares, I'm afraid that I do - just can't leave it like that ... Might do Knowing and The Post this evening and Blade Runner maybe tomorrow.

As you can see, gimp 2.10 cubic scaling currently adds some serious blurring to the image ...

Damn. Damn. Damn.

Maybe sth similar happened at Universal with Oblivion. But like my grandma used to say: Only if you don't do anything, you will make no mistakes.

I knew those BD caps looked soft. Cool...you fixed them all. We all appreciate your work...even if there are bumps in the road sometimes

Jim Collins · 05-14-2018, 12:01 PM

Anyone has screenshot comparisons for Mamma Mia (2008)?
(The 4K disc was released on May 1)!

Geoff D · 05-14-2018, 05:37 PM

Quote:

Originally Posted by Pyoko

Haven't watched the disc so I don't know how widespread it is but it seems to only appear in specific instances, and it's basically huge swathes of slow-moving blocking in the near-blacks. It's extremely bad in this shot, but it's really difficult to make out when converted to SDR so it might just be another freak OLED HDR tone-mapping issue:

I literally cannot see anything untowards in that grab at all.

andreasy969 · 05-14-2018, 06:27 PM

Quote:

Originally Posted by Geoff D

All three still smack the Blu-ray silly

Yeah, but since the main purpose of the comparisons are the details and the compression (only followed by stuff like highlight detail and general change of color) smoothed BD upscales are still somewhat less than perfect.

Unless I wanted to sell UHDs.

Quote:

Originally Posted by Spartan21

I knew those BD caps looked soft.

Well, please just tell me then next time.

Seriously.

The bitter irony is that for a moment, with one cap, I remember being slightly confused with the Knowing upscales myself. But I dismissed that thought and didn't check back ...

Quote:

Originally Posted by Jim Collins

Anyone has screenshot comparisons for Mamma Mia (2008)?
(The 4K disc was release on May 1)!

I for one don't own Mamma Mia, so cannot provide caps.

I'm usually not a fan of such lists and I'm also too lazy to enter my discs here (or elsewhere for that matter), but I just did an "UHD export" from my excel file and I own and can do the following (didn't exclude those that have comparisons somewhere already, because, again, too lazy and also not sure about some ...):

[Show spoiler]

I think I might/will always put new ones first, but (like I said before) for the most part, the order doesn't really matter to me. I'm not very interested in some myself though for varying reasons.

Pyoko · 05-14-2018, 10:43 PM

Quote:

Originally Posted by Geoff D

I literally cannot see anything untowards in that grab at all.

Me neither, I can just barely see there's something going on in motion, until I switch over to HDR then it goes haywire.

Pyoko · 05-14-2018, 11:48 PM

Marginally better compression of the grain and that's pretty much it for the 4K, not that I expected much else. I don't like the Dolby Vision presentation on my set either, as blacks are often raised to the max. I'm not talking about Nolan blacks, I'm talking about "this really looks like something is wrong" blacks.

BD left, UHD right

05-13-2018, 07:46 AM	#702
andreasy969 Blu-ray Knight Member since:Aug 2008 Trading Score:125	EDIT: obsolete - all BD caps have been fixed I went back to "Knowing" this morning to see how bad the gimp Problem really is and it's worse than I thought ... I just redid the title shot and one of the "relevant" caps (the improvement is still there), but I'm afraid I'll "have to" revisit the BD caps of Knowing, The Post and Blade Runner. Even if no one else cares, I'm afraid that I do - just can't leave it like that ... Might do Knowing and The Post this evening and Blade Runner maybe tomorrow. Anyway, here are the two I just redid to check how bad it really is: previous UHD-BD cap, BD cap properly upscaled, original BD cap, previously effed up BD upscale (gimp 2.10): As you can see, gimp 2.10 cubic scaling currently adds some serious blurring to the image ... Damn. Damn. Damn. Maybe sth similar happened at Universal with Oblivion. But like my grandma used to say: Only if you don't do anything, you will make no mistakes. Last edited by andreasy969; 05-13-2018 at 03:48 PM.

05-13-2018, 03:07 PM	#706
Pyoko Blu-ray Guru Top contributor Member since:Apr 2008 4K collection:151 Blu-ray collection:722	Three Billboards Outside Ebbing, Missouri Often noticeably sharper/more detailed with better grain. Except perhaps for the VFX, the UHD master was most likely upscaled directly from 2.8K. BD left, UHD right Last edited by Pyoko; 05-13-2018 at 03:13 PM.

05-13-2018, 05:35 PM	#709
Pyoko Blu-ray Guru Top contributor Member since:Apr 2008 4K collection:151 Blu-ray collection:722	La La Land "2K DI" Yeah I'm going to have to call bullshit on that one... Granted the BD isn't great and seems prone to aliasing, but that ain't to 2K grain on the UHD. I guess IMDb etc. are conflating the intermediate/working resolution with the final DCP resolution (as information on the former isn't as readily available.) BD left, UHD right

05-14-2018, 12:01 PM	#716
Jim Collins Senior Member Member since:May 2017 Blu-ray reviews:1	Mamma Mia? Anyone has screenshot comparisons for Mamma Mia (2008)? (The 4K disc was released on May 1)! Last edited by Jim Collins; 05-16-2018 at 10:30 AM.

05-14-2018, 11:48 PM	#720
Pyoko Blu-ray Guru Top contributor Member since:Apr 2008 4K collection:151 Blu-ray collection:722	Mother! Marginally better compression of the grain and that's pretty much it for the 4K, not that I expected much else. I don't like the Dolby Vision presentation on my set either, as blacks are often raised to the max. I'm not talking about Nolan blacks, I'm talking about "this really looks like something is wrong" blacks. BD left, UHD right

05-13-2018, 03:50 PM	#707
andreasy969 Blu-ray Knight Member since:Aug 2008 Trading Score:125	I fixed the blurred BD upscales of all 3 now - 'Knowing' catches up a little bit again now and at the same time has its sharpening back, 'The Post' has its grain back and 'Blade Runner' regains its dignity. You may want to compare all 3 again. Sorry for the little screw-up.

05-13-2018, 06:39 PM	#710
TheSweetieMan Banned Member since:Nov 2009 4K collection:515 Blu-ray collection:515	'La La Land' is a terrific looking UHD disc.

05-13-2018, 06:41 PM	#711
Pyoko Blu-ray Guru Top contributor Member since:Apr 2008 4K collection:151 Blu-ray collection:722	It would be clearer if the sentence at the end read "the mastering resolution was 2K for digital cinema." That's just the very final output though and just one of the masters. Other possible masters are SD, HD, UHD, broadcast, digital download etc. with various resolutions and specifications. It doesn't mean the first thing they did after scanning was to downscale it to 2K and then work from that, that would be the intermediate resolution, but I guess the terminology has gotten all muddled since the term DI started being applied to everything and not just the original film workflow. The UHD is definitely no upscale from 2K.

05-13-2018, 08:11 PM	#712
Geoff D Blu-ray Emperor Top contributor Member since:Feb 2009 Location:Swanage, Engerland 4K collection:1348 Blu-ray collection:2525 Blu-ray reviews: 6 Trading Score:33	LLL is a quite lovely UHD disc. RE: the caps, any signs of the extreme banding in darker shots that people were reporting before?

Best 4K Blu-ray Deals