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17th May 2018, 00:26 | #50863 | Link | |
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NGU Anti-Alias, NGU Sharp and Reconstruction are likely the best chroma upscalers, but this is pretty difficult to test with anything besides chroma upscaling test patterns. So, I use NGU Sharp blindly. I don't really do anything special besides that. I use soften edges 1 with NGU Sharp when luma doubling. Add grain can add noticeable noise to solid black textures, so I don't use it, but it probably helps as much as it harms. Neural network scalers are supposed to be able to find small detail like eyelashes and hair textures and reconstruct them. I find NGU Sharp does the best job of finding and enhancing these small details, with NGU Anti-Alias in second place. I haven't seen any examples where NGU Standard is better than NGU Sharp or NGU Anti-Alias. And NGU Soft is too soft compared to NGU Anti-Alias. I toggle the free variant of RCA with certain content with a keyboard. Everything goes back to the defaults when the video is over. If a source is too soft, I enable a profile with image enhancements because some content is just shot that way. Again, everything reverts to its defaults when the video is over. That's really about it. I did look up banding in 4K UHD and found some technical information about the combined efficiency of HEVC, a 10-bit master and high bitrates in improving compression and concluded that banding isn't as common as 8-bit Blu-ray. I have only seen limited 4K content on my 1080p display, but guess that banding in 4K UHD is probably uncommon.
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HOW TO - Set up madVR for Kodi DSPlayer & External Media Players Last edited by Warner306; 17th May 2018 at 00:32. |
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17th May 2018, 00:31 | #50864 | Link | |
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HOW TO - Set up madVR for Kodi DSPlayer & External Media Players |
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17th May 2018, 00:59 | #50865 | Link |
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I just read your profile on GitHub and now know that you worked for Microsoft and Nvidia for over 15 years. Perhaps, you should be posting here more often, unless of course you were responsible for driver development related to HTPC use. In that case, you can go somewhere else...
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HOW TO - Set up madVR for Kodi DSPlayer & External Media Players |
17th May 2018, 01:24 | #50866 | Link |
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@madjock,
I missed your bold reply. I don't think anyone would argue that a true 4K master is superior to a 1080p upscale. But that doesn't mean that upscaling doesn't have significant value. And good, sharp upscaling can can sometimes be superior if the 4K source is soft and lacking detail. Not all 4K content is razor sharp. HDR -> SDR. The tone mapping curve reduces the luminance (Y) of all pixels to fit the value set in target peak nits. The default curve compresses everything into the available luminance of the display. You will obviously lose some highlight detail by doing this, so there is an option at the bottom to sharpen these pixels to make them stand out a little more at a lower luminance. The gamut mapping algorithm corrects any RGB pixels that don't fit into the gamut after tone mapping. By focusing on luminance reduction and then creating colors, you will end up with some pixels that are out of gamut because each RGB color contains different amounts of white, so they won't scale linearly with reductions in white (luminance). They need to be corrected (estimated) into a value that can be shown by the display's available colors. The way the pixels that are too bright & too saturated are corrected depends on a balancing act between luminance and saturation. This only applies to any of the scientific tone mapping algorithms. The dumb method simply clips the offensive pixels to fit into the gamut. You can't have a perfect balance of hue, saturation and luminance, so you have to adjust each in certain amounts to make the pixel fit. This method of estimating the pixel color is called hue preserving tone mapping, as the goal is to preserve the hue while manipulating saturation and luminance to find the best balance between the two. Some people don't like the hue preservation method and instead prefer dumb tone mapping. It is all subjective as there is no way to perfectly recreate the original highlight color. It won't scale linearly with luminance. Trying to preserve the hue when tone mapping RGB pixels is recommended by Dolby and other white papers that have been written on tone mapping techniques. Hence, madshi's desire to use this method. The option to measure each frame's peak luminance should eventually lead to the creation of dynamic tone mapping like Dolby Vision or HDR10+, where the brightness changes based on the max luminance of the scene rather than use a global value like the current HDR10. I don't think this is working, yet, but should be a significant advantage when it is available. Someone can correct me if any of that is not 100% accurate. Edit: To add to that, the quick math showing how far off colors can be would be as follows: - If colors are calculated as floating point values where 0 = black and 1.0 = white, then the PQ gamma states 1.0 = 10,000 nits. - A 2,000 nit master then has an approximate (likely not exact) maximum value of 0.2 (0.2, 0.2, 0.2), which is pure white. - If the target is 100 nits, then the scaling factor is 10,000/100 = 100 times. - If you multiply 0.2 x 100 = 20. This is 20 times the maximum displayable value of 1.0, so this pixel will have to be tone mapped. - If the max value is twenty times larger than the target gamut (0.0 to 1.0), then you can imagine how many values have to be reduced to fit a 100 nit gamut. So tone mapped images will never look 100% identical to the 4K master because so many values have to be changed to fit into the gamut. Well, I hope that math is right. The 10,000/100 might not be correct.
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HOW TO - Set up madVR for Kodi DSPlayer & External Media Players Last edited by Warner306; 17th May 2018 at 02:55. |
17th May 2018, 07:40 | #50870 | Link |
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17th May 2018, 10:32 | #50872 | Link |
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I own an OPTOMA UHZ 65 laser video projector that handles very well the HDR, in fact with madvr I'm going to passthrough .... yesterday out of curiosity I wanted to use the HDR to SDR conversion, the image is more brighter, but the colors appear washed out, even if you set it in "this display is already calibrated" BT.2020, what can it depend on?....I use MPC-BE.... I also wanted to know from the owners of AMD video cards which is the most stable driver for HDR?
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17th May 2018, 11:54 | #50873 | Link |
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Does anyone know if the process HDR content by using pixel shader math option presumes the display is already calibrated and just send the information in the same way passthrough would? Or does it take any LUTS loaded into MadVR into consideration?
My issue is that if I calibrate my display (430nits) for HDR using DisplayCal and MadVRTPG I have a problem when playing 4000nit content (sections of Mad Max are a great example) where very bright highlights turn red. The only way I can prevent this is by increasing the peak luminence to around 2500nits but this has the side effect of bringing the average luminence down and everything becomes quite dark. Setting the peak luminence to 1000nits under pixel shader math gives me almost identical results to passthrough and is the expected peak luminance for a display around the 400nit mark but I also want to calibrate my display as I know it's slightly off. Is it possible to use pixel shader math and have a LUT loaded? and has anyone else experienced this highlight issue on very bright 4000nit content? |
17th May 2018, 12:38 | #50874 | Link |
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I got a quick smooth motion question:
In case I want to use madvr's smooth motion feature to bring a 23,976 fps to 60hz display mode, do I have to use reclock to sync my audio? Or is the bitstreamed audio untouched?
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Intel i5 6600, 16 GB DDR4, AMD Vega RX56 8 GB, Windows 10 x64, Kodi DS Player 17.6, MadVR (x64), LAV Filters (x64), XySubfilter .746 (x64) LG 4K OLED (65C8D), Denon X-4200 AVR, Dali Zensor 5.1 Set |
17th May 2018, 13:25 | #50876 | Link | |
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Using D3D11/Exclusive/10bit/4:4:4/30Hz refresh/let madVR decide (HDR)/SmoothMotion OFF. Some 60fps/4K are choppy, not sure why, probably decoding, haven't investigated fully yet.
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17th May 2018, 13:27 | #50877 | Link |
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@Clown shoes
Does anyone know if the process HDR content by using pixel shader math option presumes the display is already calibrated and just send the information in the same way passthrough would? Or does it take any LUTS loaded into MadVR into consideration? From Warner306 post on a KODI Forum : convert HDR content to SDR by using pixel shader math: HDR is converted to SDR. The display receives SDR content. convert HDR content to SDR by using an external 3DLUT: HDR content is converted to SDR. The display receives SDR content. If you supply multiple 3DLUT files, the one which best matches the source gamut will be used. The 3DLUT receives untouched R'G'B' HDR (PQ) data, applies tone & gamut mapping, then outputs R'G'B' data in the display's native gamut and transfer function. process HDR content by using pixel shader math: The display receives HDR content, but the HDR source is downconverted to the target specs. process HDR content by using an external 3DLUT: The display receives HDR content, but the 3DLUT downconverts the HDR source to some extent. The 3DLUT input/output is R'G'B' HDR (PQ). The 3DLUT applies some tone and/or gamut mapping. https://forum.kodi.tv/showthread.php...942#pid2238942 |
17th May 2018, 13:43 | #50879 | Link |
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@foozoor
Linux more advanced ? As a distro hopper for a couple of years I don't think so. You have to download codecs for everything, I had to do multiple fixes to stop screen tearing in one way or another for each distro with their own individual faults. KODI does not play DTS-HD with KODI unless you start it with flags to avoid Pulseaudio and even then it does not work all the time, its no simple task removing Pulseaudio and if you have a distro that allows you, everything else goes to pot. I gave Linux more than enough changes and sometimes new releases just regressed every time, sharing a folder demanded rocket science on most as well. Nvidia drivers are nowhere near as good on Linux as well. Windows is much better at Multimedia and straight out of the box in my opinion. |
17th May 2018, 13:47 | #50880 | Link | |
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direct compute, dithering, error diffusion, madvr, ngu, nnedi3, quality, renderer, scaling, uhd upscaling, upsampling |
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