HDR -> SDR conversion
Re: HDR -> SDR conversion
Thanks for the suggestions, guys. I need to make a DGHDRtoSDR() update and then I can look at this stuff.
Do you feel GOOOD? Say YEAH! Wheee.
Do you feel GOOOD? Say YEAH! Wheee.
Re: HDR -> SDR conversion
great filter!
i'm very looking forward to the HLG2SDR function.
i'm very looking forward to the HLG2SDR function.
Re: HDR -> SDR conversion
I have same 2160p 10-bit TS sources in HLG / BT.2020 (mediainfo reported), and I want to re-encode them to 1080p in SDR / BT.709 for archiving.
When I play a TS source, the color looks mostly fine, it seems to be a 4K UHD source.
You mean that I can re-encoding without any filters?
Re: HDR -> SDR conversion
Any chance you could give me a link to one of those transport streams? You can use DGSplit to cut the first 50MB. Only you can decide if it looks "good enough" with no special processing. With one of your streams I can try it both ways and we'll see how they compare.
Re: HDR -> SDR conversion
I have provided 3 clips, 50MB per clip, thank you for your helpadmin wrote: ↑Tue Sep 03, 2019 8:50 amAny chance you could give me a link to one of those transport streams? You can use DGSplit to cut the first 50MB. Only you can decide if it looks "good enough" with no special processing. With one of your streams I can try it both ways and we'll see how they compare.
http://138.68.0.28:8008/trim_162.ts
http://138.68.0.28:8008/trim_187.ts
http://138.68.0.28:8008/trim_203.ts
Re: HDR -> SDR conversion
Thank you very much. I will make a proper HLG to SDR filter and see how it compares.
Re: HDR -> SDR conversion
This is interesting:
https://www.youtube.com/watch?v=yGSjun9gsbs
It shows that, compared to a proper conversion to SDR 709, playing HLG 2020 directly is "OK" but it is much darker and there are color shifts.
Probably your clips will perform similarly. Seems to me there is indeed a good justification for a new filter.
https://www.youtube.com/watch?v=yGSjun9gsbs
It shows that, compared to a proper conversion to SDR 709, playing HLG 2020 directly is "OK" but it is much darker and there are color shifts.
Probably your clips will perform similarly. Seems to me there is indeed a good justification for a new filter.
Re: HDR -> SDR conversion
Guys, I have added a 'HDR' field to the HEVC Info dialog. This will show "PQ" for HDR10, "HLG" for HLG, and is blank for SDR.
I also figured out how to properly detect HDR. There are two ways to signal it: 1) through the transfer_characteristics (16 is PQ, 18 is HLG), and 2) through SEI messages. Previously I was looking only at the presence/absence of SEI messages. Now I look at both. You have to look at both because a HLG stream can signal 709 via transfer_characteristics together with a preferred_transfer_characteristics SEI specifying HLG. This allows for backward compatibility of HLG with 709 displays. Refer to T-REC-H.Sup18-201710-I!!PDF-E.pdf for details:
https://www.itu.int/rec/T-REC-H.Sup18-201710-I
Will slipstream it after some regression testing.
I also figured out how to properly detect HDR. There are two ways to signal it: 1) through the transfer_characteristics (16 is PQ, 18 is HLG), and 2) through SEI messages. Previously I was looking only at the presence/absence of SEI messages. Now I look at both. You have to look at both because a HLG stream can signal 709 via transfer_characteristics together with a preferred_transfer_characteristics SEI specifying HLG. This allows for backward compatibility of HLG with 709 displays. Refer to T-REC-H.Sup18-201710-I!!PDF-E.pdf for details:
https://www.itu.int/rec/T-REC-H.Sup18-201710-I
Will slipstream it after some regression testing.
Re: HDR -> SDR conversion
I found the official HD version here:
https://www.youtube.com/watch?v=ih1l6wb7LhU
for these clips:
trim_187.ts at 35:03
trim_203.ts at 38:02
I can't find trim_162.ts in HD version, I think SDR ver. and HDR ver. are different editions.
https://www.youtube.com/watch?v=ih1l6wb7LhU
for these clips:
trim_187.ts at 35:03
trim_203.ts at 38:02
I can't find trim_162.ts in HD version, I think SDR ver. and HDR ver. are different editions.
Re: HDR -> SDR conversion
Thanks but I don't know how to download youtube videos.
- Bullwinkle
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- Joined: Thu Sep 05, 2019 6:37 pm
Re: HDR -> SDR conversion
Hello there culture lovers. Today we take a look at the modern day HLG to SDR known as The Good Stuff. Here is one fetching picture. They call me fetching. Fetching all the pixels ain't saving whoa! Ooh. Okay that is all for today next week the meaning of Randomness and Beauty.
Re: HDR -> SDR conversion
Thank you, zys4416.
I have the HLG EOTF coded and apparently working. I want to compare the results to the HD versions you linked, and also to the results of some other conversion filters. If things look good, I'll implement it fully into DGHDRtoSDR (with a mode parameter for PQ or HLG) and add it to DGIndexNV as well.
I have the HLG EOTF coded and apparently working. I want to compare the results to the HD versions you linked, and also to the results of some other conversion filters. If things look good, I'll implement it fully into DGHDRtoSDR (with a mode parameter for PQ or HLG) and add it to DGIndexNV as well.
- Bullwinkle
- Posts: 338
- Joined: Thu Sep 05, 2019 6:37 pm
Re: HDR -> SDR conversion
Sure but watch me pull a rabbit out of a hat... Ooh not what I had in mind randomness is beautiful.
Re: HDR -> SDR conversion
Just discovered there is a BT.2100-2 while I was coding off of BT.2100-1. The HLG EOTF is a bit different in BT.2100-2 so I'll have to revise the implementation accordingly. No big deal.
Re: HDR -> SDR conversion
I tried both of these. Each simply brought up a player and played the stream. I could not see how to download the stream.
Re: HDR -> SDR conversion
Re: HDR -> SDR conversion
Great, thank you. You are so kind.
Re: HDR -> SDR conversion
I've got the HLG EOTF re-coded and working. And I have DGHDRtoSDR() modified to support both PQ and HLG via a mode parameter. I'll add the HLG support to DGIndexNV and then give y'all both of them. Whee!
Re: HDR -> SDR conversion
I've got HLG to SDR working in DGIndexNV. It's kinda nice. You can set up the HLG conversion and then just click and unclick 'Enable HDR to SDR' to see the difference between real HLG conversion and backwards compatible display. The color shifts from backwards compatible handling become very obvious.
Now I have to do code reviews, regression testing, and documentation.
Now I have to do code reviews, regression testing, and documentation.