Fixing/changing HDR data on a UHD rip?

MKV playback, recompression, remuxing, codec packs, players, howtos, etc.
Post Reply
Dan-O
Posts: 6
Joined: Mon Nov 19, 2018 4:08 am

Fixing/changing HDR data on a UHD rip?

Post by Dan-O »

I hope this is the a good subforum to ask this because although this has to do with a specific UHD disc, this is not a MakeMKV error at all.

Long story short is that a UHD has HDR, but this title is WAY too dark. This is not how the film is supposed to be at all. We know this is true because the HD version on Blu-ray looks way brighter, as does the HD digital version, and even people on other forums said that the iTunes UHD stream was originally too dark, but then 'fixed' later.

So here is my question:
After ripping the UHD to a MKV file, is there any way to fix/hack/edit the HDR/brightness data, such that we can effectively correct the brightness on this title?

Here is the data from MediaInfo:
Video
ID : 1
ID in the original source medium : 4113 (0x1011)
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L5.1@High
HDR format : SMPTE ST 2086, HDR10 compatible
Codec ID : V_MPEGH/ISO/HEVC
Duration : 1 h 33 min
Bit rate : 64.4 Mb/s
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0 (Type 2)
Bit depth : 10 bits
Bits/(Pixel*Frame) : 0.324
Stream size : 41.9 GiB (92%)
Language : English
Default : No
Forced : No
Color range : Limited
Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : BT.2020
Mastering display luminance : min: 0.0000 cd/m2, max: 1000 cd/m2
Maximum Content Light Level : 565 cd/m2
Maximum Frame-Average Light Level : 61 cd/m2

Original source medium : Blu-ray
And here is the data from a DIFFERENT UHD title for comparison
Video
ID : 1
ID in the original source medium : 4113 (0x1011)
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L5.1@High
HDR format : SMPTE ST 2086, HDR10 compatible
Codec ID : V_MPEGH/ISO/HEVC
Duration : 1 h 58 min
Bit rate : 93.7 Mb/s
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0 (Type 2)
Bit depth : 10 bits
Bits/(Pixel*Frame) : 0.471
Stream size : 77.5 GiB (92%)
Language : English
Default : No
Forced : No
Color range : Limited
Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : BT.2020
Mastering display luminance : min: 0.0001 cd/m2, max: 1000 cd/m2
Maximum Content Light Level : 1000 cd/m2
Maximum Frame-Average Light Level : 400 cd/m2

Original source medium : Blu-ray
The big difference is in the last few lines. The bad title is SUPER low, while the other title seems more reasonable. I spot-checked a few other titles, and they were in line with the other good title, and nothing was as low as the title I'm having an issue with.

I know that the other title's data won't be a 1-to-1 comparison, but if there's a way to dump the other title's HDR/brightness data into the bad title, maybe it'll help fix the problem? Is this even possible in any manor? Or would it need to be a scene-by-scene adjustment (I'd be willing to try this too...)?

Any help/guidance would be appreciated! I'm really interested to see if anyone has even tackled this sort of thing, or if there's any interest in trying it. It would be awesome to have this UHD rip 'fixed' so it can truly be the best possible copy of the film, instead of a sore disappointment.
Post Reply