How to get the MaxCLL/MaxFALL values ?

[Nico8583]

Hi,
I would like to recode some of my movies and I woud like to know more about MaxCLL/MaxFALL values.
MediaInfo can report it but I read somewhere MaxCLL/MaxFALL can be different inside a same movie when there are some M2TS parts. Each M2TS can get a different value.
How can I retrieve the right values to use with x265 ?
Thank you !

[cool advertise]

You can probably safely use the MaxCLL / MaxFALL values reported by mediainfo.
I checked and compared the hdr metadata of the untouched version with the 4k bluray of over 120 4k bluray films, and the only 4k bluray that reported incorrect MaxCLL / MaxFALL values when using the untouched version as the source was Alita: Battle Angel.
As for Alita: Battle Angel we talked about it here:
https://forum.doom9.org/showthread.php?t=176876
However in case you would like to check out some 4k bluray movies, simply compare the main playlist of the 4k bluray movie and the untouched version of the film, and apply the rule to use the highest value for MaxCLL / MaxFALL among all m2ts parts of the main bluray 4k playlist.
In the case of Alita: Battle Angel, the untouched version reported these values:

Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : Display P3
Mastering display luminance : min: 0.0001 cd/m2, max: 1000 cd/m2
Maximum Content Light Level : 233 cd/m2
Maximum Frame-Average Light Level : 63 cd/m2

while the 4k bluray playlist reported these:

General
Complete name : E:\Alita - Angelo Della Battaglia [2019] [BLURAY FULL 4K]\BDMV\PLAYLIST\00800.mpls
Format : Blu-ray Playlist
File size : 3.81 KiB
Duration : 2 h 1 min
Overall bit rate mode : Variable
Overall bit rate : 4 b/s

Video #1
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L5.1@High
HDR format : SMPTE ST 2094 App 4, Version 1, HDR10+ Profile A compatible
Codec ID : 36
Duration : 35 s 952 ms
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0 (Type 2)
Bit depth : 10 bits
Color range : Limited
Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : Display P3
Mastering display luminance : min: 0.0001 cd/m2, max: 1000 cd/m2
Maximum Content Light Level : 233 cd/m2
Maximum Frame-Average Light Level : 63 cd/m2
format_identifier : HDMV
Source : 00687.m2ts

Video #3
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L5.1@High
HDR format : SMPTE ST 2094 App 4, Version 1, HDR10+ Profile A compatible
Codec ID : 36
Duration : 1 h 55 min
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0 (Type 2)
Bit depth : 10 bits
Color range : Limited
Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : Display P3
Mastering display luminance : min: 0.0001 cd/m2, max: 1000 cd/m2
Maximum Content Light Level : 737 cd/m2
Maximum Frame-Average Light Level : 130 cd/m2
format_identifier : HDMV
Source : 00688.m2ts

Video #5
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L5.1@High
HDR format : SMPTE ST 2094 App 4, Version 1, HDR10+ Profile A compatible
Codec ID : 36
Duration : 2 min 1 s
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0 (Type 2)
Bit depth : 10 bits
Color range : Limited
Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : Display P3
Mastering display luminance : min: 0.0001 cd/m2, max: 1000 cd/m2
Maximum Content Light Level : 1000 cd/m2
Maximum Frame-Average Light Level : 18 cd/m2
format_identifier : HDMV
Source : 00674.m2ts

Video #7
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L5.1@High
HDR format : SMPTE ST 2094 App 4, Version 1, HDR10+ Profile A compatible
Codec ID : 36
Duration : 3 min 28 s
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0 (Type 2)
Bit depth : 10 bits
Color range : Limited
Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : Display P3
Mastering display luminance : min: 0.0001 cd/m2, max: 1000 cd/m2
Maximum Content Light Level : 505 cd/m2
Maximum Frame-Average Light Level : 13 cd/m2
format_identifier : HDMV
Source : 00689.m2ts

Applying the rule to use the highest value for MaxCLL / MaxFALL
it will be understood that these values must be used:

Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : Display P3
Mastering display luminance : min: 0.0001 cd/m2, max: 1000 cd/m2
Maximum Content Light Level : 1000 cd/m2
Maximum Frame-Average Light Level : 130 cd/m2

[Nico8583]

Hi, thank you for the answer ! I'll look at it again but if Alita is the only one it's well. Thank you.

[Balling]

>and apply the rule to use the highest value for MaxCLL / MaxFALL among all m2ts parts of the main bluray 4k playlist.

No, you should preserve the original values if they change. Mp4 permits change of static metadata.

[cool advertise]

>and apply the rule to use the highest value for MaxCLL / MaxFALL among all m2ts parts of the main bluray 4k playlist.

No, you should preserve the original values if they change. Mp4 permits change of static metadata.

It is "benwaggoner" final thought on the subject, it doesn't come from me.
https://forum.doom9.org/showthread.php?p=1884671#post1884671

[benwaggoner]

It is "benwaggoner" final thought on the subject, it doesn't come from me.
https://forum.doom9.org/showthread.php?p=1884671#post1884671
Thank you for the mention.

And yes, after further investigation into how "static" static metadata is, it appears safe to concatenate different clips with different metadata together. Some TVs will blend between differences in their tone mapper. Some TVs pretty much ignore that metadata anyway.

Dynamic metadata ala Dolby Vision or HDR10+ is much preferable if an option, of course.

[Balling]

Not only it is permited, it is mandated to support change in static metadata on 1 frame boundary per CTA 861-G and -H.