HDR -> SDR conversion

These CUDA filters are packaged into DGDecodeNV, which is part of DGDecNV.
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Re: HDR -> SDR conversion

Post by admin » Tue Jul 24, 2018 10:02 am

YV12 is not YUV420P16, though it can be stored that way (8 bits are wasted). The source is 4:2:0 so saving it as 4:4:4 cannot retain extra source detail.

Dion is asking for me to output YUV420P16. I am asking for it to be justified with evidence. Talking about 4:4:4 is not germane to that. Can you output YUV420P16 with 10-bit data from HDRTools?

Narkyy
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Re: HDR -> SDR conversion

Post by Narkyy » Tue Jul 24, 2018 10:55 am

In the case of HDRTools, YV12 is YUV420P16. I know it's not usually.
The source is 4:2:0 so I can't grasp how it looks much better when ending in 4:4:4, looks just like madVR but madVR says 4:2:0

As for the banding, I don't think there's a difference between 8 bit and higher as long as there's dithering at the last step.
Compared against everything, banding is just more pronounced with the lighter darks/gamma from DGHDRtoSDR.

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Re: HDR -> SDR conversion

Post by admin » Tue Jul 24, 2018 12:03 pm

Narkyy wrote:
Tue Jul 24, 2018 10:55 am
Compared against everything, banding is just more pronounced with the lighter darks/gamma from DGHDRtoSDR.
Where is the evidence of banding? I've asked for evidence and all you guys do is make unsupported claims. Dion just makes useless posts like "I thought this tool outputs 8-bit, am I wrong?"

First you're talking about detail retention now you're talking about banding. Then you talk about 4:4:4 from some other tool. You're starting to irritate me big time.

I hacked a quick version to output the full 10 bits in P16. I open the YV12 and P16 versions in their own VDub2 windows. I see NO difference in detail. I see NO banding in either one. I speculated earlier about the reason but nobody took any notice of it. You seem to have a naive "10-bit good, 8-bit bad" dogma in your heads, and don't think about context.

If you don't substantiate your claims, I'm going to shut down this discussion as it is just FUD at this point. You want to use some other tool, go for it, I don't care. If it's about dithering, then ask for dithering and give a sample that shows that it's needed. Then I will be happy to consider it.

Dion
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Re: HDR -> SDR conversion

Post by Dion » Tue Jul 24, 2018 2:48 pm

Thought it was common knowledge that banding is caused by the down conversion from a higher bit master to 8bit?

But anyways.. Here is an example of 8bit vs 16bit vs DGHDRtoSDR. I could not use DGHDRtoSDR in this test for 16bit cause I am sure its going straight to 8bit. That is why I asked if that is what your plugin is doing.

8bit vs 16bit vs DGHDRtoSDR
ImageImageImage

and for good measure..

16bit to 8bit back to 16bit. Info lost...
Image

edit: With Narkyy help was able to get HDRTools to work.. It outputs 16bit Tonemapping correctly no banding either.
Image

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Re: HDR -> SDR conversion

Post by admin » Tue Jul 24, 2018 4:20 pm

Now you're talking, thank you. But I need the source sample and all the scripts to be able to replicate it. What did you use for the first two shots? How did you take the screenshots?

If you give me what I need and the banding is eliminated by outputting 16-bits I'll be happy to add that to the filter. But I have to be able to verify that it is working as intended, and not just blindly release something. So, source sample, scripts, and how did you get the screenshots, please.

Dion
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Re: HDR -> SDR conversion

Post by Dion » Wed Jul 25, 2018 1:29 am

https://www.dropbox.com/s/qiwo2v5j6b9c9 ... 2.mkv?dl=1

Make sure you have the latest Avisynth+ otherwise 16bit will error out and display nothing..
https://github.com/pinterf/AviSynthPlus ... /tag/r2728

16 Bit
DGSource("Annihilation-002.dgi", fulldepth=True)
z_Spline36Resize(1920, 1080)
DGHDRtoSDR
DGSource("Annihilation-002.dgi", fulldepth=True)
z_Spline36Resize(1920, 1080)
DGHDRtoSDR(tm="mobius", light=250)
8 Bit
DGSource("Annihilation-002.dgi", fulldepth=True)
z_Spline36Resize(1920, 1080)
ConvertBits(8)

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Re: HDR -> SDR conversion

Post by admin » Wed Jul 25, 2018 10:26 am

Thank you, Dion.

Here is build 1.8, which adds a fulldepth parameter to output 10-bit SDR stored in YUV420P16.

http://rationalqm.us/misc/DGHDRtoSDR_1.8.rar

BTW, you have tm="mobius". That is not valid syntax for build 1.7, so I suppose you used an earlier
version.

Dion
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Re: HDR -> SDR conversion

Post by Dion » Wed Jul 25, 2018 1:02 pm

Thanks.. Looks to be working.. :salute:

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Re: HDR -> SDR conversion

Post by admin » Wed Jul 25, 2018 1:23 pm

You're welcome. Thank you for pushing for this addition.

Nginx
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Re: HDR -> SDR conversion

Post by Nginx » Wed Jul 25, 2018 10:52 pm

Thank you very much ~

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