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

[teddyballgame]

Originally Posted by PeterTHX

This means every disc is a Czech disc!

[panasonicst60]

Originally Posted by Stacey Spears

The wide channels are present. Switch base to 9.1 and the wides show up on the base layer tests. Assuming this is what you are talking about.

The Atmos tests had to be encoded by Dolby. The commercially available Atmos encoder does not have the ability to do what we needed. At the time of creation, 2.0 of the renderer was available. At that time, sound bars and displays started using 2.0 while AVRs/SSPs were still on 1.0. There was a change that altered the levels between 1.0 and 2.0. Dolby had to use special metadata that is supposed to make them produce the proper levels on both versions for calibration.

Marc worked directly with Dolby when creating the DAMFs for all of the channels.

Finally got a chance to check this again, but even after switching base layer to 9.1 and selecting Atmos my wides do not play any sound. All other channels in my 9.1.4 plays fine, just not my wides. Not sure if I'm missing something....

[Stacey Spears]

Sounds like a possible bug in the Emotiva then. You get no sound at all? If you switch the emotiva to 7.1 and play the left or right wides, do you get a phantom image?

What happens if you try DTS:X and the wides?

I will let Dolby know about the wides on Emotiva and see what they say. We tested them on the Trinnov Altitude 32.

[DisplayCalNoob]

Originally Posted by Stacey Spears

Youthman
The AV Experience with Special Guest Stacey Spears and Don Munsil - YouTube

Really, enjoyed this one. When I have the new disc, I plan to do a comparison of the horses grazing in the snow. I will look for the overall differences in image quality and the detail that should be present, to see well the HDR10 tone mapping performs against Dolby Vision.

Also, I have more questions for Dolby if your are accepting them. Which UHD blu-ray player has best Dolby Vision implementation?

Do display manufacturer engineers attend Dolby(assuming they are aware)workshops or training for proper implementation of Dolby Vision?

Do you guys use the Spears and Munsil disc to help you evaluate displays, miniLED, QD-OLED, MLA OLED specifically for tone mapping and gamut mapping?

[Stacey Spears]

Originally Posted by DisplayCalNoob

Really, enjoyed this one. When I have the new disc, I plan to do a comparison of the horses grazing in the snow. I will look for the overall differences in image quality and the detail that should be present, to see well the HDR10 tone mapping performs against Dolby Vision.

Also, I have more questions for Dolby if your are accepting them. Which UHD blu-ray player has best Dolby Vision implementation?

Do display manufacturer engineers attend Dolby(assuming they are aware)workshops or training for proper implementation of Dolby Vision?

Do you guys use the Spears and Munsil disc to help you evaluate displays, miniLED, QD-OLED, MLA OLED specifically for tone mapping and gamut mapping?

HDR10 tone mapping is not standardized, so each display does its own thing. One person messaged me recently and noticed that static tone mapping ends up clipping on this shot while preserving all the detail with dynamic tone mapping enabled. For this reason, I recommend a custom static tone curve on LG because they let you create one.

I am sorry, the question before you was the last we can take. Seriously though, there is no limit to questions, ask away. We will do our best.

Dolby is a black box in terms of algorithms. Every Dolby product should be using Dolby's algorithms. Does not mean there are no bugs. e.g. OPPO and Sony BD players have the same MediaTek inside, but must be running different firmware as the OPPO has bugs that Sony, and others do not, such as the levels changing. From a video standpoint, the Panasonic 820 and 1000 are your best bet. They are not perfect by any means as they have ringing in chroma due to their style of chroma upsampling. They are slower and don't support the native output of the source like OPPO does with Source Direct. Source Direct is great if you are using a video processor like Lumagen and/or madVR Envy, just to use those two as an example. Maybe your display has the best algorithms in the world, so source direct would use the display algorithms. Samsung and LG compete against each other and this pushes them to make advances.

Bottom line, Dolby does its processing, but you are still limited to other algorithms that come before or after. When using Dolby Vision, the conversion from 4:2:0 to 4:2:2 is done by Dolby. At least the first one! What I mean by that is, if your player can output 4:2:0, it will first get converted to 4:2:2 and then back to 4:2:0 for output. Not ideal! I am dealing with this when sending 8K60 from an NVIDIA RTX 6000 Ada to an 8K Samsung LCD. (55") This is for my day job. Use any of our patterns with the chroma alignment diamonds. Compare Dolby Vision to HDR10 on any player with MediaTek and you will see the odd artifacts that occur. You may also want to compare 4:2:2 and 4:4:4 in the HDR10 scenario. You will see the ugliest streaks that go through the chroma diamonds. This also manifests on the lower right magenta'ish colors on the scaling patterns. It is flat out ugly! This also goes to show how bad we are at seeing color artifacts as finding this in real-world content is much more difficult.

Quick tangent. I was implementing a chroma noise reduction algorithm in OpenCL. I had a bug that made the blue channel look like a stereo image where you had two images offset. in RGB, you could not see the issue, but when you looked at just the blue channel, you had this dual image. It was a real eye opener for me. I wish I still had the test image, I would share it. Compressionists would often put the display into blue-only mode (Sony BVM HD CRT) to look at compression artifacts when QC'ing a movie. So many artifacts in the blue channel due to compression, but you never see them given how bad we are at seeing color detail.

My favorite front projector was the Samsung SP-A900B HD DLP. It lacked in contrast compared to LCOS. But it did just about everything else as good as you can get for HD SDR. Uniformity, color accuracy, sharpness, chromatic aberration, it was just good. Contrast, compared to JVC, was trash. And if you were sensitive to rainbows from a single chip DLP, that was not great for you either. For HDR, I have gone to flat panel as I think OLED is the current best in the consumer space. If I had the money, I would have a Sony CLED at home. I don't have that kind of money or space. If MicroLED every comes to be, or better yet, true Quantum Dot emissive displays, then even better. I am not married to any one tech or company. I wish Panasonic would release their OLEDs in the US.

No idea on training, but I doubt such a thing is available. Dolby works closely with their partners. You can break Dolby into two parts, the professional side and consumer side. The professional side is great! The consumer implementation side could use some work. To be fair, they are a small team and have way too much work, which is pretty much the norm in the tech world. Often the people working on this stuff are pretty motivated but under staffing with the skilled workers is always a problem no matter where you are in tech.

For the last question, I assume you are asking everyone. The entire reason the disc exists is my desire to make products better. I built the tool I wanted to evaluate displays. Calibration is just one tiny use of the disc. I wanted a tool that display manufacturers could use to build better products. I pretty much gave up my weekends and vacations over the last four years to get this disc done. In fact, I will be taking my first real vacation (not even real at this point) in a couple weeks and will be offline (no phone or Internet other than streaming movies and TV) for a couple of weeks. I mention this in case people wonder why we are radio silent in a couple weeks. I think I will disable our contact page during that time so people don't get frustrated when we don't respond.

When we created the DVD Benchmark, and eventually the Progressive Scan Shootout, we were seriously lacking in the proper tools / patterns to evaluate players. I wish we would have had this disc back then. We did the best we could at the time with the help of Joe Kane and Guy Kuo. The WHQL disc really helped on the deinterlacing side.

One of the new patterns, that most won't be able to utilize, is the chome upsampling evaluation pattern. This was made for Mathias to help improve his AI based chroma upsampling algorithm. At the time we made it, Universal had reached out to see if we could build a pattern for that purpose too.

BTW, sorry for these wall of text posts. Same can be said for the long video interviews. I would rather have too much than too little. I am really hoping we can get the specific video interviews going before end of summer so we can get everyone more details on the disc itself. Vs. retelling the origin story over and over again. I was thanking that the first Tom Holland Spiderman movie was not the origin story yet again.

[Wendell R. Breland]

Very informative post, thanks Stacey.

[panasonicst60]

Originally Posted by Stacey Spears

Sounds like a possible bug in the Emotiva then. You get no sound at all? If you switch the emotiva to 7.1 and play the left or right wides, do you get a phantom image?

What happens if you try DTS:X and the wides?

I will let Dolby know about the wides on Emotiva and see what they say. We tested them on the Trinnov Altitude 32.

Regardless of what I do with the configurations, there is no sound coming from my wide channels. In movies they do work on some Atmos soundtracks. Might be a Emotiva bug as you stated. I'll reach out to them. Thanks Stacey!

[Stacey Spears]

Originally Posted by panasonicst60

Regardless of what I do with the configurations, there is no sound coming from my wide channels. In movies they do work on some Atmos soundtracks. Might be a Emotiva bug as you stated. I'll reach out to them. Thanks Stacey!

Does the base layer pan go through your wides? They are different than specific channel locations, but that would be good info to have.

Thank you again!

[panasonicst60]

Originally Posted by Stacey Spears

Does the base layer pan go through your wides? They are different than specific channel locations, but that would be good info to have.

Thank you again!

In the panning test the wide channels work as they should. Very odd...

[Stacey Spears]

The panning test is a normal Atmos operation. The speaker pink noise are placed at precise coordinates. So the wides are placed at the specific x, y and z location in space. It is possible your processor does not have the wide's at the location Dolby defined for the wides. That is just a best guess at this point.

[DisplayCalNoob]

@Stacey Spears Entire text had me glued to my screen, it's not very often you enjoy a read on the internet.

Do you use Vudu for streaming movies? There streamed films, appear to go through changes over time. It's as if they are using trims they weren't using before. There is more detail (tone mapping I assume).

[Stacey Spears]

Originally Posted by panasonicst60

Regardless of what I do with the configurations, there is no sound coming from my wide channels. In movies they do work on some Atmos soundtracks. Might be a Emotiva bug as you stated. I'll reach out to them. Thanks Stacey!

If you can test the Emotiva set to 7.1 and play the wides with the disc set to 9.1 to see if you get a phantom image, that would really help. Assuming this is not too much trouble. We have another customer with a 7.1.4 Emotiva RMC-1 who I have asked to try the 9.1 phantom image test and to also set it up as 9.1.4, if it has that ability, and then use his left and right speakers as the wides to see what he encounters.

I appreciate you taking the time to test and report your issues, thank you! With any luck, the disc is doing its job and finding real bugs. Once I have the info back from both of you, I will contact Dolby with the details.

I will be curious what you encounter with DTS. DTS is the odd one because it really seems like a 7.1.4 format. DTS:X Pro is a decode side feature, not an encode side feature. DTS created the tests for us as well. We disabled the 6 channel overhead option because, in our testing, we found that the middle speakers were really phantom images from the front and rear. The 6 channel is still on disc, you just have to press the right arrow a few times on one of the radio buttons (I forget which one off hand) and then the 6-channel top layer radio button becomes enabled. I think you can also switch to DTS using the audio bottom on the remote if in the 6-channel Dolby mode.

[Stacey Spears]

Originally Posted by DisplayCalNoob

@Stacey Spears Entire text had me glued to my screen, it's not very often you enjoy a read on the internet.

Do you use Vudu for streaming movies? There streamed films, appear to go through changes over time. It's as if they are using trims they weren't using before. There is more detail (tone mapping I assume).

Yes and no. I have Vudu and all the movies in there are from the digital copy that came with the various BDs I purchased. There are a few where we paid to upgrade to the UHD or the HDR version, but in general I don't use Vudu for new movies.

Since Covid, I may have seen 5 movies in the theater. Maybe even all Marvel movies. At this point, 95% of my viewing has been TV shows. I have no issue streaming TV shows, but for movies, I want optical disc as I want the highest quality experience.

Are you saying that a given movie has changed or they have offered different versions over time, such as HD, UHD and HDR?

One issue with streaming is you never know which layer you are getting or which encode. Its not uncommon for a service to have dozens of copies of the same movie with different encoder settings or CODECs do to all the devices on the market. And with adaptive bitstream streaming, content is made up of different layers at different resolutions and bitrates. The idea is if your network bandwidth is low or gets congested, it can switch layers to a lower bitrate / quality version to try and keep the stream going. This is why you may see the quality fluctuate.

To give you an example, when Xbox launched 1080p Instant On, somewhere between 2007-2009, we had 10 layers. The top layer was 1080p full time and the highest bitrate. (Maybe 10 Mbps) The lowest layer might have been 240p. The GOPs were 2-seconds long. This meant it could change layers every 2-seconds to increase or decrease the quality level. We used VC-1 at the time and we actually changed the resolutions within a layer as well. Everyone else had fixed resolutions for each layer. Later on, when they switched to AVC, they locked down to a single resolution per layer as well. The idea was you would start the content at the lowest quality, which gave you the instant on aspect. You could quickly ramp up and even skip layers if the bandwidth was good. I think we even had trick play layers to simulate fast forward and rewind.

[DisplayCalNoob]

Originally Posted by Stacey Spears

Yes and no. I have Vudu and all the movies in there are from the digital copy that came with the various BDs I purchased. There are a few where we paid to upgrade to the UHD or the HDR version, but in general I don't use Vudu for new movies.

Since Covid, I may have seen 5 movies in the theater. Maybe even all Marvel movies. At this point, 95% of my viewing has been TV shows. I have no issue streaming TV shows, but for movies, I want optical disc as I want the highest quality experience.

Are you saying that a given movie has changed or they have offered different versions over time, such as HD, UHD and HDR?

One issue with streaming is you never know which layer you are getting or which encode. Its not uncommon for a service to have dozens of copies of the same movie with different encoder settings or CODECs do to all the devices on the market. And with adaptive bitstream streaming, content is made up of different layers at different resolutions and bitrates. The idea is if your network bandwidth is low or gets congested, it can switch layers to a lower bitrate / quality version to try and keep the stream going. This is why you may see the quality fluctuate.

To give you an example, when Xbox launched 1080p Instant On, somewhere between 2007-2009, we had 10 layers. The top layer was 1080p full time and the highest bitrate. (Maybe 10 Mbps) The lowest layer might have been 240p. The GOPs were 2-seconds long. This meant it could change layers every 2-seconds to increase or decrease the quality level. We used VC-1 at the time and we actually changed the resolutions within a layer as well. Everyone else had fixed resolutions for each layer. Later on, when they switched to AVC, they locked down to a single resolution per layer as well. The idea was you would start the content at the lowest quality, which gave you the instant on aspect. You could quickly ramp up and even skip layers if the bandwidth was good. I think we even had trick play layers to simulate fast forward and rewind.

Most of my movies on Vudu are the same (just digital copies from the UHD BD).

One of the movies that was actually purchased on Vudu, is MM Fury Road. While given a look, I noticed more detail, not resolution but more HDR detail.

[panasonicst60]

Originally Posted by Stacey Spears

If you can test the Emotiva set to 7.1 and play the wides with the disc set to 9.1 to see if you get a phantom image, that would really help. Assuming this is not too much trouble. We have another customer with a 7.1.4 Emotiva RMC-1 who I have asked to try the 9.1 phantom image test and to also set it up as 9.1.4, if it has that ability, and then use his left and right speakers as the wides to see what he encounters.

I appreciate you taking the time to test and report your issues, thank you! With any luck, the disc is doing its job and finding real bugs. Once I have the info back from both of you, I will contact Dolby with the details.

I will be curious what you encounter with DTS. DTS is the odd one because it really seems like a 7.1.4 format. DTS:X Pro is a decode side feature, not an encode side feature. DTS created the tests for us as well. We disabled the 6 channel overhead option because, in our testing, we found that the middle speakers were really phantom images from the front and rear. The 6 channel is still on disc, you just have to press the right arrow a few times on one of the radio buttons (I forget which one off hand) and then the 6-channel top layer radio button becomes enabled. I think you can also switch to DTS using the audio bottom on the remote if in the 6-channel Dolby mode.

When I get a chance I will test and report back. Thanks for the support!

[Stacey Spears]

Originally Posted by panasonicst60

When I get a chance I will test and report back. Thanks for the support!

My friend with the other Emotiva was able to confirm your results and he also ran the other tests I asked you to run. This is where things get interesting!

When setting the SSP to 7.1, there was no phantom image when sending bitstream to the Emotiva. When changing from bitstream to LPCM, where the OPPO does the decode (in his setup), there is a phantom image for the wides!

With DTS:X, he only ever heard a phantom image for the wides in all scenarios regardless if the system was 7.1 or 9.1. For DTS:X, I suspect wides are like the middle speakers on the 6 channel height, they don't really support 9.1 or .6 of any sort and always produce a phantom image for those channels. I am making some big assumptions on DTS:X, but I suspect this further shows that DTS:X is a 7.1.4 format. Nothing wrong with that as 7.1.4 is an amazing setup.

If anyone else has a 9.1 system, we would love to hear your results, no pun intended. It would also be great if you can list your AVR/SSP. The more data I can send to Dolby, the better.

What is your opinion of the montage Atmos soundtrack? And what do you think of the first audio piece vs. the 2nd, which changes between the tulips and watch shot change?

In general:
1. Test the wides for both 7.1 an 9.1 configuration.

a. When set to 7.1, do you hear a phantom image?

b. When set to 9.1 do you hear the pink noise through the wide speaker?

2. Repeat step 1 for both bitstream and LPCM.

And please list your AVR/SSP and BD player with FW versions. I use BD to mean 4K/UHD BD player. I call this out because I know some get very pedantic about using BD when it is 4K/UHD BD. You have no idea! I write this as someone who is also pedantic.To be more PC, I am flat out anal with some of these things!

[panasonicst60]

Our Emotiva preamps only has DTS:X and not DTS:X Pro, which has the additional of wides. When changing from bitstream to LPCM I do get a phantom image as your friend. All demos with the Atmos soundtrack sounds awesome! My wides are fully engage in the demo.

[Stacey Spears]

Originally Posted by panasonicst60

Our Emotiva preamps only has DTS:X and not DTS:X Pro, which has the additional of wides. When changing from bitstream to LPCM I do get a phantom image as your friend. All demos with the Atmos soundtrack sounds awesome! My wides are fully engage in the demo.

As I said, DTS:X Pro is just a decode side feature. I believe it uses NEO 6 to create new channels as there is no DTS:X Pro encoder or format.

[FilmFreakosaurus]

Originally Posted by Stacey Spears

As I said, DTS:X Pro is just a decode side feature. I believe it uses NEO 6 to create new channels as there is no DTS:X Pro encoder or format.

DTS: X Pro is indeed an end-user upmixer that helps expand the 7.1.4 fixed DTS: X tracks (or 7.1.5 IMAX Enhanced tracks) to more speaker positions.

I've heard it's an offshoot of Neural: X since engaging the Neural: X mode that is included with the DTS: X Pro package while playing standard stereo, 5.1, or 7.1 tracks does the same thing.

[DisplayCalNoob]

@Stacey Spears

You made a comment that reminded me of this article https://hometheaterhifi.com/technica...-introduction/, about bluray players HDMI ports having incorrect values that negatively affected colorspace conversion.

Do you think what's in the article, which I believe is in part 2 applies to today for UHD Bluray players? If so, is that just the difference between using RGB over YCbCr for proper conversion.