Spears & Munsil 4K UHD HDR Benchmark (Test Discs) May 15, 2023

[kfbkfb]

I haven't read this whole thread, maybe this has already been asked.

Dolby Atmos Test Audio question:

Dolby Digital Plus, Dolby AC-4 and Dolby TrueHD are all capable of containing Dolby Atmos content.

I request some Dolby Atmos test audio (on the UHD test Blu-ray) with:
1. Dolby Digital Plus
a. Lowest permissible data rate w/Atmos content
b. Highest data rate w/Atmos content
2. Dolby AC-4
a. Lowest permissible data rate w/Atmos content
b. Highest data rate w/Atmos content
3. Dolby TrueHD
a. Lowest permissible data rate w/Atmos content
b. Highest data rate w/Atmos content

The Atmos content should be something demanding to test the perceptual coders.


Thank you

Kirk Bayne

[Stacey Spears]

Originally Posted by kfbkfb

I haven't read this whole thread, maybe this has already been asked.

Dolby Atmos Test Audio question:

Dolby Digital Plus, Dolby AC-4 and Dolby TrueHD are all capable of containing Dolby Atmos content.

I request some Dolby Atmos test audio (on the UHD test Blu-ray) with:
1. Dolby Digital Plus
a. Lowest permissible data rate w/Atmos content
b. Highest data rate w/Atmos content
2. Dolby AC-4
a. Lowest permissible data rate w/Atmos content
b. Highest data rate w/Atmos content
3. Dolby TrueHD
a. Lowest permissible data rate w/Atmos content
b. Highest data rate w/Atmos content

The Atmos content should be something demanding to test the perceptual coders.


Thank you

Kirk Bayne

Hi Kirk,

Thank you for the feedback. What you are discussing is more in line with CODEC testing, which is not our goal. I don't know if DD+ or AC4 are even allowed on BD.

Our Atmos tones are for setting speaker levels, checking bass management and looking for audio gaps in the sound as they pan around the room. I hope that makes sense. These are bandwidth limited pink noise at 24/48.

AC3 is the only mandatory format on BD for Dolby. Because of this, if you include TrueHD, it must also include AC3. TrueHD does not have a bitrate option as it is lossless.

The Atmos tones were all encoded by Dolby for reasons we will discuss in a future video. We provided them with the DAMFs and then they encoded them.

[Oniiz86]

Originally Posted by Stacey Spears

Confirmed the issue is an OPPO bug and does not occur on Panasonic.

However, at this point in time, I think Dolby on BD is a real disappointment.
1. They appear to be using 709, instead of 2020, upsampling so there is a half pixel vertical delay between Y and C. Verified this on both OPPO and Panasonic.
2. The 4:2:2 to 4:4:4 conversion in the Dolby engine, on the display side, is very low quality and lacks chroma resolution compared to HDR10 on the same display.
3. Dolby has chroma ringing in their upsampling, similar to Panasonic. You can see it come and go on the OPPO when you switch between Dolby Vision and HDR10.

Maybe I will invest in a Lumagen or MadVR Envy and use HDR10 on all Dolby titles.

I also tested player vs. tv-led. Player-led has the same issues where black is crushed more and the top two boxes on the CSE pattern don't blend, all the time! At first I thought the OPPO bug might simply be playing in player-led, but that was not the case as player-led has some other differences as well.

I did find that if I let a pattern play until the player loops it, it actually resolves the bug on OPPO. Not sure why it does but nothing else but a power cycle does.

It seems the OPPO is rife with bugs compared to other manufacturers if only OPPO had stuck around long enough to eradicate some or most of them, then their players could be deemed as "reference", the Panasonics seemingly have no Chroma bugs whatsoever & are pretty much reference for video save for a couple of quirks with Lionsgate DV titles concerning flickering & freezing issues.

[Stacey Spears]

Originally Posted by Oniiz86

It seems the OPPO is rife with bugs compared to other manufacturers if only OPPO had stuck around long enough to eradicate some or most of them, then their players could be deemed as "reference", the Panasonics seemingly have no Chroma bugs whatsoever & are pretty much reference for video save for a couple of quirks with Lionsgate DV titles concerning flickering & freezing issues.

If OPPO existed today, I am 100% confident they would fix every issue. They cared so much about quality! They would have even pushed Dolby to ship a new SDK with fixes.

When they were working on their first DVD player, they emailed Don and I and asked us to consult because they said they wanted to build the best DVD player ever. We were busy at the time, but Kris Deering stepped up and helped them. When they were building their first BD player, they pushed us to make our first disc. If it were not for OPPO, we may not have a disc today. They even told us, don't worry if the disc makes them look bad, they will fix the issues. And there was a bug found during the 83s development that I thought there was no way they could fix with FW because it was in the decoder. They fixed it before it shipped with FW!

We worked with anther company to build a disc for them. They told us to make them look good and everyone else look bad. Just two examples of different approaches companies take.

The OPPO, from a usability standpoint. (Speed, source direct, etc...) is the best. It just has so many bugs around audio and video and that is due to lack of proper tools to test. Our disc came way to late. You don't want to use 4:4:4 out of the player due to nearest neighbor upsampling for example. This is 4:2:2 to 4:4:4.

Panasonic has ringing in chroma due to the bicubic upsampling. It produces higher resolution chroma overall, just wish they could implement an anti-ringing algorithm. The Dolby issues are not their fault either since they are in the Dolby SDK. Wish they would apply pressure to Dolby.

I really hope that users and reviewers make a bunch of noise when the new disc ships. Maybe we can apply pressure to get Dolby to fix their bugs.

The Dolby tools that create the content do the proper downsample, its just the playback side that is borked. The professional side of Dolby Vision is done properly. The consumer playback side is amateur hour. Not only in the player, which has an almost zero chance of fixing, but also on the display side. I did a factory reset on my LG this weekend and I am using the factory Dolby cal because the display is flat out wrong after calibration. And as I have said before, player-led is not usable from a quality standpoint. Maybe this is hyperbole since the bugs are subtle, but Dolby is a premium format and should not have these amateur hour issues. Like they say, a few bad apples spoil the bunch and Dolby should toss those bad apples. They know who they are!

David and I are actually trying to see if we can work around the Dolby Vision issue when switching to HDR10 and back. We found one case where it does reset. The behavior may change once we actually have the menu in place with proper background videos. Should know more in a couple of weeks.

[Oniiz86]

Originally Posted by Stacey Spears

The OPPO, from a usability standpoint. (Speed, source direct, etc...) is the best. It just has so many bugs around audio and video and that is due to lack of proper tools to test. Our disc came way to late. You don't want to use 4:4:4 out of the player due to nearest neighbor upsampling for example. This is 4:2:2 to 4:4:4.

I thought OPPO's 203/205 utilised "Nearest Neighbor" the easiest form of Chroma upsampling in all instances of its processing, the UDP-205 was tested & performed poorly in regards to Chroma by forum user @Sledgehamma some time ago.

[Stacey Spears]

Originally Posted by Oniiz86

I thought OPPO's 203/205 utilised "Nearest Neighbor" the easiest form of Chroma upsampling in all instances of its processing, the UDP-205 was tested & performed poorly in regards to Chroma by forum user @Sledgehamma some time ago.

I recall the 4:2:0 to 4:2:2 being something like bilinear while 4:2:2 to 4:4:4 being nearest neighbor. (NN) I am going from memory and can be wrong. 709 is interstitial while 2020 is co-sited, in the vertical direction.

What make NN bad is that you can't deal with the location of chroma being co-sited vs. interstitial and thus you get the half pixel offset/shift/delay between Y and C.

[Pagey123]

So much good technical information in this thread! I'm loving every post! /nerdgasm

[David M]

Originally Posted by kfbkfb

I haven't read this whole thread, maybe this has already been asked.

Dolby Atmos Test Audio question:

Dolby Digital Plus, Dolby AC-4 and Dolby TrueHD are all capable of containing Dolby Atmos content.

I request some Dolby Atmos test audio (on the UHD test Blu-ray) with:
1. Dolby Digital Plus
a. Lowest permissible data rate w/Atmos content
b. Highest data rate w/Atmos content
2. Dolby AC-4
a. Lowest permissible data rate w/Atmos content
b. Highest data rate w/Atmos content
3. Dolby TrueHD
a. Lowest permissible data rate w/Atmos content
b. Highest data rate w/Atmos content

The Atmos content should be something demanding to test the perceptual coders.


Thank you

Kirk Bayne

BD (and by extension UHD BD) supports DD+ (although it's rarely used since lossless compression is a better match for a format with this much capacity), but not AC4.

[Keenan]

Originally Posted by Stacey Spears

The Dolby tools that create the content do the proper downsample, its just the playback side that is borked. The professional side of Dolby Vision is done properly. The consumer playback side is amateur hour. Not only in the player, which has an almost zero chance of fixing, but also on the display side. I did a factory reset on my LG this weekend and I am using the factory Dolby cal because the display is flat out wrong after calibration. And as I have said before, player-led is not usable from a quality standpoint. Maybe this is hyperbole since the bugs are subtle, but Dolby is a premium format and should not have these amateur hour issues. Like they say, a few bad apples spoil the bunch and Dolby should toss those bad apples. They know who they are!

David and I are actually trying to see if we can work around the Dolby Vision issue when switching to HDR10 and back. We found one case where it does reset. The behavior may change once we actually have the menu in place with proper background videos. Should know more in a couple of weeks.

I'm guessing this means that streaming content(Netflix, etc.) would have these DoVi playback issues as well?

[Stacey Spears]

Originally Posted by Keenan

I'm guessing this means that streaming content(Netflix, etc.) would have these DoVi playback issues as well?

No, not necessarily.

The powers that be seem to only care about streaming. So maybe streaming is okay, but don't know without actual patterns to confirm.

[Penton-Man]

Originally Posted by Stacey Spears

....I really hope that users and reviewers make a bunch of noise when the new disc ships. Maybe we can apply pressure to get Dolby to fix their bugs.

Good luck. Given the situation these days, there’s little motivation to correct things as compared to 10 years ago - https://www.prweb.com/releases/2011/5/prweb8483801.htm

[wxman2003]

Wow, didn't realize DV on disc was a mess. Sounds like it's best just to turn DV off no matter what player you are using. It pains me to say this, but maybe Samsung was right not buying into the DV hype.

[Stacey Spears]

Originally Posted by wxman2003

Wow, didn't realize DV on disc was a mess. Sounds like it's best just to turn DV off no matter what player you are using. It pains me to say this, but maybe Samsung was right not buying into the DV hype.

The technology is sound, the delivery into our hands, not so much! It is frustrating to all of us because we care so much about quality.

And to Penton's point, the only way to get someone to care is to impact their bottom line.

[wxman2003]

Originally Posted by Stacey Spears

The technology is sound, the delivery into our hands, not so much! It is frustrating to all of us because we care so much about quality.

And to Penton's point, the only way to get someone to care is to impact their bottom line.

Like you said earlier, they only seem to care about streaming nowadays.

[5150z]

As wxman2003 said in an earlier post, the 2016 LG Oled line has an issue tone-mapping HDR10 content. Which I learned on my 65B6. Forcing DV(on my Oppo 203)on HDR10 content improved things very nicely. It's what I use all the time now. Are these 709 to 2020 upscales and any other anomalies noticeable while viewing content, or only with patterns on your disc? These things can be so frustrating. Thank you for all your wealth of knowledge SS.

[FilmFreakosaurus]

Originally Posted by wxman2003

Wow, didn't realize DV on disc was a mess. Sounds like it's best just to turn DV off no matter what player you are using. It pains me to say this, but maybe Samsung was right not buying into the DV hype.

Unless the papers on DV for streaming leaked in the past have been updated, it looked like streaming DV was (and maybe still is) even worse or lower quality given the extreme compression necessary for internet files for Netflix, Amazon, etc., plus they do not do 12 bit Full Enhancement Layer (FEL) encodings for streaming that some 4k discs have (8 or 10 bit only).

[David M]

Originally Posted by FilmFreakosaurus

Unless the papers on DV for streaming leaked in the past have been updated, it looked like streaming DV was (and maybe still is) even worse or lower quality given the extreme compression necessary for internet files for Netflix, Amazon, etc.,

That's standard of all streaming video compared to disc, and isn't related to any HDR format.

[Penton-Man]

Originally Posted by Stacey Spears

The technology is sound, the delivery into our hands, not so much! It is frustrating to all of us because we care so much about quality.

And to Penton's point, the only way to get someone to care is to impact their bottom line.

That’s the problem Stacey, like it or not, physical media and its advocates doesn’t carry the same financial leverage as in thee old days. Resources are prioritized elsewhere, HDR is driven by streamers - https://www.youtube.com/watch?v=gxK69r0UG3k#t=2m50s
You think Dolby Vision IQ was expedited by UHD Blu-ray playing videophiles?

Dolby Vision IQ | Dolby Vision | Dolby - YouTube

[GREM]

Originally Posted by Stacey Spears

Confirmed the issue is an OPPO bug and does not occur on Panasonic.

Have you had a chance to check Sony's players?

[SeeMoreDigital]

Originally Posted by Stacey Spears

Confirmed the issue is an OPPO bug and does not occur on Panasonic.

[Show spoiler]However, at this point in time, I think Dolby on BD is a real disappointment.
1. They appear to be using 709, instead of 2020, upsampling so there is a half pixel vertical delay between Y and C. Verified this on both OPPO and Panasonic.
2. The 4:2:2 to 4:4:4 conversion in the Dolby engine, on the display side, is very low quality and lacks chroma resolution compared to HDR10 on the same display.
3. Dolby has chroma ringing in their upsampling, similar to Panasonic. You can see it come and go on the OPPO when you switch between Dolby Vision and HDR10.

Maybe I will invest in a Lumagen or MadVR Envy and use HDR10 on all Dolby titles.

I also tested player vs. tv-led. Player-led has the same issues where black is crushed more and the top two boxes on the CSE pattern don't blend, all the time! At first I thought the OPPO bug might simply be playing in player-led, but that was not the case as player-led has some other differences as well.

I did find that if I let a pattern play until the player loops it, it actually resolves the bug on OPPO. Not sure why it does but nothing else but a power cycle does.

Out of interest...

After playing an HDR10 'disc' source does the OPPO respond any differently playing MEL encoded content or FEL 'disc' encoded content. Or is the players response the same?

Given this new information, I guess there is a benefit to backing-up Dolby Vision encoded discs to 'main movie' only .m2ts files and utilising the OPPO's AVCHD folder playback option.

Cheers and many thanks.