HDR to SDR StaxRip Problem

[Z2697]

Reading is a hard to learn skill it seems.

[jay123210599]

@Z2697 @GeoffreyA

All right, I'm sending you my HDR video. Use Placebo on StaxRip and see if you could fix the error.

https://www.mediafire.com/file/fn71j...2/HDR.mkv/file

[GeoffreyA]

I tried it and this is what I found. You've got to double-click on Placebo in the filter list on the left, then uncomment the following lines:

ConvertToYUV420()
ConvertBits(10)

However, x265 still fails because it thinks it is receiving HDR input. So, open x265 options. Under "Input," remove all Dolby Vision settings, such as the profile and RPU. Then, under "VUI," set Colorprim, Transfer, and Colormatrix to BT.709. Lastly, under "VUI 2," remove all HDR light settings, setting CLL and FALL to 0, deselecting "Emit content light," and removing Master Display information. If you know the correct x265 profile, level, and tier, set it under "Basic." 10-bit 1080p SDR content should be Main10, Level 4.1, High Tier.

All in all, it should work, but I think it's simpler to use FFmpeg directly. Generally, changes one makes are sent downstream to the rest of the pipeline, making it automatic.

[jay123210599]

Originally Posted by GeoffreyA

I tried it and this is what I found. You've got to double-click on Placebo in the filter list on the left, then uncomment the following lines:

ConvertToYUV420()
ConvertBits(10)

However, x265 still fails because it thinks it is receiving HDR input. So, open x265 options. Under "Input," remove all Dolby Vision settings, such as the profile and RPU. Then, under "VUI," set Colorprim, Transfer, and Colormatrix to BT.709. Lastly, under "VUI 2," remove all HDR light settings, setting CLL and FALL to 0, deselecting "Emit content light," and removing Master Display information. If you know the correct x265 profile, level, and tier, set it under "Basic." 10-bit 1080p SDR content should be Main10, Level 4.1, High Tier.

All in all, it should work, but I think it's simpler to use FFmpeg directly. Generally, changes one makes are sent downstream to the rest of the pipeline, making it automatic.

I just uncommented those lines and that worked, but I have one more problem. When playing the outputted video in PotPlayer, the video still had the HDR tag even though it has been converted to SDR. How do I change that?

https://imgbox.com/qqC31GFI

[GeoffreyA]

As above, go into x265 options, removing everything related to Dolby Vision and HDR, and importantly, setting the colour matrix, transfer, and primaries to BT.709. That should do it. In MediaInfo, there should be no sign of BT.2020, DV, or anything of that sort. If the problem persists, post the MediaInfo properties of the encoded file.

[manolito]

Hi,

here is my simple version which does not use LibPlacebo (my old Thinkpad does not support it). In my upload there are 3 different versions using DGHDRtoSDR, plus 2 zimg based versions. My target format is X264, because it is easier to use and in my view it offers better quality.

Here is the link: (only valid for 3 days)
https://we.tl/t-j17Hrq58fP


Cheers
manolito



EDIT:
Sorry for the typo in the readme. In the second line of cource I mean "Video" and not "Audio"

[jay123210599]

Can SDR videos have color primaries and matrix coefficients of BT.2020?

[GeoffreyA]

Originally Posted by jay123210599

Can SDR videos have color primaries and matrix coefficients of BT.2020?

I don't think the matrix and primaries can be, but perhaps the BT.2020 transfer function. At any rate, it's advisable to stick with 709 for all three.

[FranceBB]

Also, given that it's not guaranteed that libplacebo has updated the frame properties, make sure they're all set to BT709 now in Avisynth so that anything downstream will know.

Put those at the end of the script:

#Remove bad frame properties
propclearall()

#Populate frame properties correctly
propSet("_ColorRange", 1) #Limited TV Range
propSet("_Matrix", 1) #BT709
propSet("_Transfer", 1) #BT709
propSet("_Primaries", 1) #BT709