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Playing HDR in Theater desktop

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#21 stettler OFFLINE  

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Posted 16 October 2018 - 06:46 PM

No, it's a condition that windows stipulates. It won't allow it unless it's full screen. That's what haasn was saying. I recently wrestled with it to see what it actually took to make HDR to pass through on windows. It was excruciating. If your PC is dedicated to only watching video, then sure. But that isn't my use case.

So all I've needed to do with mpv, is enable UHD 10 bit on my display, adjust the display settings for my environment....press play. All the other stuff is just because I'm a control freak :)

 

You didn't read correctly what Microsoft stipulated. It's perfectly possible to play HDR movies in a window. Did you tested it? I just did with VLC and with Microsoft movies app. If you think about it, that's logical: When you activate HDR in Windows, it force everything in HDR mode, desktop and all. The restriction is when streaming HDR movie on a built-in display. That's probably related to copy protection and/or how streaming provides (Netflix,...) detect if you can/are allowed to stream HDR content.



#22 stettler OFFLINE  

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Posted 16 October 2018 - 06:58 PM

I've switched between the shield and my HTPC, to compare the picture. Is there a difference? Of course, because I'm using PQ. But the difference is only really noticable to those who know what to look for and are actually looking for differences.

 

I tried between VLC, the Microsoft movies app in HDR and mpc. VLC and the app are very similar. There is a pretty big and very visible difference with mpc. 

 

Again, I am not saying that the mpc result is bad or even less good than other software that do HDR passthrough. What I am saying is that there is a pretty visible difference.

 

As you said, you just put your TV in UHD, fumble with its settings to get something that looks fine to you and press play. Seems you never bothered to calibrate your monitor or TV. The whole point of calibration is to have a consistent result. If using one player give very different results than using another, you can't expect consistent results.

 

(And PQ has nothing to do with this in itself: PQ is a part of HDR10. If you use a player that passthrough HDR, then you are also using PQ)

 

What mpv developers think is that they can do PQ at least as well as your TV. Fine, that's perhaps even true. But PQ is only 1 part of HDR. The thing is, when a TV receive an HDR signal, it knows it has to apply PQ. When it receive a signal that it doesn't recognize as HDR, it may well apply another form of processing (and as stated above, PQ will depend of the specificity of the display's hardware. The TV manufacturer knows them, mpv doesn't)


Edited by stettler, 16 October 2018 - 07:08 PM.


#23 Doofus OFFLINE  

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Posted 16 October 2018 - 08:53 PM

You didn't read correctly what Microsoft stipulated. It's perfectly possible to play HDR movies in a window. Did you tested it? I just did with VLC and with Microsoft movies app. If you think about it, that's logical: When you activate HDR in Windows, it force everything in HDR mode, desktop and all. The restriction is when streaming HDR movie on a built-in display. That's probably related to copy protection and/or how streaming provides (Netflix,...) detect if you can/are allowed to stream HDR content.


Yeah, but I have to enable windows HDR, which changes the entire display, and it's horrible. My desktop sucks with it like that, unless I adjust it massively. I have no need to do stupid stuff like that with mpv. I get everything I want, the way I'm using mpv. I want to be able to adjust the picture with software.

#24 Doofus OFFLINE  

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Posted 16 October 2018 - 08:56 PM

I tried between VLC, the Microsoft movies app in HDR and mpc. VLC and the app are very similar. There is a pretty big and very visible difference with mpc.

Again, I am not saying that the mpc result is bad or even less good than other software that do HDR passthrough. What I am saying is that there is a pretty visible difference.

As you said, you just put your TV in UHD, fumble with its settings to get something that looks fine to you and press play. Seems you never bothered to calibrate your monitor or TV. The whole point of calibration is to have a consistent result. If using one player give very different results than using another, you can't expect consistent results.

(And PQ has nothing to do with this in itself: PQ is a part of HDR10. If you use a player that passthrough HDR, then you are also using PQ)

What mpv developers think is that they can do PQ at least as well as your TV. Fine, that's perhaps even true. But PQ is only 1 part of HDR. The thing is, when a TV receive an HDR signal, it knows it has to apply PQ. When it receive a signal that it doesn't recognize as HDR, it may well apply another form of processing (and as stated above, PQ will depend of the specificity of the display's hardware. The TV manufacturer knows them, mpv doesn't)


You've misunderstood everything I've said I've done. You've basically repeated everything I've been saying.

#25 Doofus OFFLINE  

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Posted 16 October 2018 - 09:16 PM

Ok so let's do this. I have a feeling you're testing mpv with windows HDR enabled. That will screw everything up. So let's compare outputs. Do you have Avengers Infinity War in HDR? That's got lots of colorful bright scenes. Take a screenshot of any scene you want, using HDR pass through. Then I'll take a screenshot with mpv of that scene. Then we can see a direct comparison. That'll be informative. I'd actually like to see that, myself.

#26 Jdiesel OFFLINE  

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Posted 16 October 2018 - 09:58 PM

I don't think taking a screenshot will work. If the display is doing any processing the screenshot won't be representitive of what is actually shown on the display as it is happening later in the output chain. The correct way would be to use test patterns and a colorimeter to see what is actually happening. I personally use ChromaPure and a Xrite i1 Pro

#27 Doofus OFFLINE  

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Posted 16 October 2018 - 10:33 PM

I don't think taking a screenshot will work. If the display is doing any processing the screenshot won't be representitive of what is actually shown on the display as it is happening later in the output chain. The correct way would be to use test patterns and a colorimeter to see what is actually happening. I personally use ChromaPure and a Xrite i1 Pro

 

Yeah, I get that, but I'm trying to ignore that we are all nerds :D and trying to get a broader perspective. The majority of people will just buy a new display, plug it in, mess with it a little bit, then just try to play something. At that point, the only thing that matters is the picture good enough. For people like us, (and we are in the minority), it's an entirely different animal. Joe public isn't going to precisely calibrate and configure their equipment. They aren't going to jump through all the hoops that is needed for concise application of HDR metadata. To that end, mpv is excellent. Joe public is looking at their screen, not calibration equipment. And I very much doubt that most people have the visual acuity to see such subtle differences. Like an audiophile having perfect pitch. The rest of us don't hear what they hear. So a screenshot would be more of a 'realworld' representation.



#28 stettler OFFLINE  

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Posted 17 October 2018 - 01:24 AM

Ok so let's do this. I have a feeling you're testing mpv with windows HDR enabled.

 

 

I am obviously not testing mpv with Windows HDR on!

 

 

Yeah, I get that, but I'm trying to ignore that we are all nerds :D and trying to get a broader perspective. The majority of people will just buy a new display, plug it in, mess with it a little bit, then just try to play something. At that point, the only thing that matters is the picture good enough.

 

That's your opinion. It's called "Emby Theater" after all. Many people that goes to all the trouble of setting-up a home theater are going to have at least some passing interest in proper calibration. If all they want is to play some movies on their new TV, they will just dump the videos on an external HDD and plug it to their TV: That's way easier and a lot less work.



#29 stettler OFFLINE  

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Posted 17 October 2018 - 01:31 AM

I don't think taking a screenshot will work. If the display is doing any processing the screenshot won't be representitive of what is actually shown on the display as it is happening later in the output chain. The correct way would be to use test patterns and a colorimeter to see what is actually happening. I personally use ChromaPure and a Xrite i1 Pro

 

Exactly. All the processing is done by display device (The calibration need to apply to other devices, like a UHD bluray player, and not just to the HTPC).

 

You would need to take photography of the screen and it's very difficult to do meaningful comparions that way (specially in HDR).



#30 Doofus OFFLINE  

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Posted 17 October 2018 - 01:46 AM

Many people that goes to all the trouble of setting-up a home theater are going to have at least some passing interest in proper calibration. If all they want is to play some movies on their new TV, they will just dump the videos on an external HDD and plug it to their TV: That's way easier and a lot less work.

 

I disagree. I'm a home theater enthusiast, I have no interest in pointing a meter at my display. I trust my eyes. Comparing HDR passthrough to how mpv handles it, is negligible. Having said that, the tone mapping algorithms are continually being improved. At this time, HDR passthrough is BS, and superfluous. It's old technology. With HLG and HDR10+ on the horizon, it's dead tech. mpv already supports HLG. Software is the way forward. 



#31 stettler OFFLINE  

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Posted 17 October 2018 - 02:03 AM

ok, no comment.



#32 PrincessClevage OFFLINE  

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Posted 17 October 2018 - 02:50 AM

I had trouble getting HDR to engage without enabling HDR in Windows 10 until I updated my nvidia gpu driver and rang tv manufacturer to see what colour format it supported which turns out to be 4:2:2 10bit 4K, only then would HDR engage in ET and mpv (without enabling in the Windows 10 setting).
I also spent some amount of time calibrating by eye with the use of contrast and brightness patterns where I am reasonably comfortable with the out put on various types of HDR video content, I do have some buts tho..
I have purchase some Harry potty HDR and some dark scene are terrible which leads me to think that HDR passthrough makes sense to allow the tv to adjust to various input contrast and brightness levels as designed by the manufacturer rather than a compromise by software layer.

#33 stettler OFFLINE  

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Posted 17 October 2018 - 04:29 AM

I had trouble getting HDR to engage without enabling HDR in Windows 10 until I updated my nvidia gpu driver and rang tv manufacturer to see what colour format it supported which turns out to be 4:2:2 10bit 4K, only then would HDR engage in ET and mpv (without enabling in the Windows 10 setting).

 

How are you doing it? You are using a custom mpv configuration file?

 

As far as I understand, you have to call mpv with  "--target-prim=bt.2020"  (if the movie is in bt.2020)  else mpv is going to automatically transform it to bt.709 (which is not a wide gamuts). Then, as mpv is not passing HDR metadata, you have to manually switch your TV to bt.2020.

 

That's what I am getting with my beamer: When playing a HDR10 movie with mpv, the beamer says the signal is bt.709 and so use bt.709. If I force it to use bt.2020 then the colors are off.

 

Basically, if you dont use "--target-prim=bt.2020" mpv will "downgrade" wide gamut to standard gamut (bt.709). If the movie is already in standard gamut (bt.601 and bt.709) it will leave it untouched.

 

I think there is a confusion because when people say they want HDR, they are usual not speaking of the gamma curve only. They want the whole deal that is part of HDR10, including the rec.2020 wide gamut, 10 bits color depth, PQ and color calibration metadata .



#34 PrincessClevage OFFLINE  

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Posted 17 October 2018 - 05:07 AM

How are you doing it? You are using a custom mpv configuration file?

As far as I understand, you have to call mpv with "--target-prim=bt.2020" (if the movie is in bt.2020) else mpv is going to automatically transform it to bt.709 (which is not a wide gamuts). Then, as mpv is not passing HDR metadata, you have to manually switch your TV to bt.2020.

That's what I am getting with my beamer: When playing a HDR10 movie with mpv, the beamer says the signal is bt.709 and so use bt.709. If I force it to use bt.2020 then the colors are off.

Basically, if you dont use "--target-prim=bt.2020" mpv will "downgrade" wide gamut to standard gamut (bt.709). If the movie is already in standard gamut (bt.601 and bt.709) it will leave it untouched.

I think there is a confusion because when people say they want HDR, they are usual not speaking of the gamma curve only. They want the whole deal that is part of HDR10, including the rec.2020 wide gamut, 10 bits color depth, PQ and color calibration metadata .

What is a Beamer ?
1dbe2158e62b3f6fea9dcdd5d4648031.jpg

#35 stettler OFFLINE  

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Posted 17 October 2018 - 05:21 AM

What is a Beamer ?
 

 

A projector. (in this case, an epson eh-tw9300w)



#36 stettler OFFLINE  

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Posted 17 October 2018 - 09:02 AM

What is a Beamer ?
1dbe2158e62b3f6fea9dcdd5d4648031.jpg

 

 

Yes, I also have bt.2020 in the stats:

 

antman-UHD-HDR-bt2020.jpg

 

 

The beamer says it's bt.709 but that's normal: without the HDR metadata, it doesn't have anyway to know it should change color space:

 

antman-UHD-HDR-bt2020-beamer_info.jpg


Edited by stettler, 17 October 2018 - 09:04 AM.


#37 stettler OFFLINE  

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Posted 17 October 2018 - 09:10 AM

The problem is that if the beamer was really receiving bt.2020, I should set it manually to bt.2020:

 

antman-UHD-HDR-bt2020-beamer_bt2020.jpg

 

Now compare it to setting the beamer to bt.709:

 

antman-UHD-HDR-bt2020-beamer_bt709.jpg

 

Obviously, setting the beamer to bt,2020 results in wrong colors. So either mpv is really messing with the colors or it is sending a bt.709 signal to the beamer. (and take my words on it, using VLC with Windows in HDR mode or using a UHD bluray player produce a result that is a lot nearer to the above bt.709 picture than to the bt.2020!)



#38 PrincessClevage OFFLINE  

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Posted 17 October 2018 - 09:17 AM

What OS are you running? If win 10 if you enable windows HDR setting what does the projector report for the same media?

#39 stettler OFFLINE  

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Posted 17 October 2018 - 09:35 AM

And now look the result if I call mpv with the "--target-prim=bt.2020" parameter:

 

antman-UHD-HDR-bt2020-target-prim.jpg

 

Obviously, that's the more correct result!

 

All along, when people say that they are getting correct results and  "wide gamut" with ET and mpv, they are wrong: They are getting a downgrade to normal gamut (bt.709). And if they force their TV to bt.2020 and  mess with the color settings to try to get an ok result, they are just making things worse.

 

If you want to display correctly a HDR10 movie (bt.2020) with mpv, the only way is to set the manually the  "--target-prim=bt.2020" parameter. If you don't, mpv with downgrade the color space to bt.709. 

 

If you only play HDR bt.2020 movies, that's ok I guess: you can manually edit your mpv configuration file. But if you play both HDR bt.2020 and HDR/SDR bt.709, that mean that you must each time edit mpv configuration file _and_ manually change the TV color space because HDR metadata aren't passed to it.

 

Personally, I can live with this "fake" HDR. We are still missing things but the result is, imho, good enough. But I can't edit my mpv configurtion and change my TV settings each time I want to play something that is SDR or HDR.



#40 stettler OFFLINE  

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Posted 17 October 2018 - 09:40 AM

What OS are you running? If win 10 if you enable windows HDR setting what does the projector report for the same media?

 

Yes Windows 10. When you enable Windows 10 HDR, the signal sent to the display will always be in HDR. My beamer will report "bt.2020 HDR" and I don't have to change the color space manually because the HDR metadata are already telling the display what it should use.

 

That work fine with HDR compatible players like VLC, MadVR, Microsoft movie player, PowerDVD,...  But that won't work with mpv because mpv is doing part of the processing that your display should normally do when in HDR mode.







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