Where to post.... How to tell if a video file has High Dynamic Range (HDR).

[everway9]

Hi everyone.

I hope y'all doing good today.


I have a question but I really don't know which would be the correct section of the forum to post it in.


My question is.......

I'm wondering if it is possible to check if a 4K video is encoded with HDR by checking the file/codec information in MediaInfo or a similar codec information utility.

Is there a certain codec which would be unique for a video which has HDR?

I know I can just play the video file on a HDR enabled display to check if it does have HDR or not but I'm just curious to know if there's a way to tell by just looking at the file information.



So please can you tell me where I should post this, or even better... answer my question?


Many thanks in advance.

[sneaker]

MediaInfo shows such infos for the HEVC codec. See bottom lines:

General
Complete name                            : Exodus_UHD_HDR_Exodus_draft.mp4
Format                                   : MPEG-4
Format profile                           : Base Media
Codec ID                                 : isom (isom/iso2/mp41)
File size                                : 246 MiB
Duration                                 : 47 s 787 ms
Overall bit rate mode                    : Variable
Overall bit rate                         : 43.2 Mb/s
Writing application                      : Lavf56.15.103

Video
ID                                       : 1
Format                                   : HEVC
Format/Info                              : High Efficiency Video Coding
Format profile                           : Main 10@L5.1@High
Codec ID                                 : hev1
Codec ID/Info                            : High Efficiency Video Coding
Duration                                 : 47 s 750 ms
Bit rate                                 : 42.8 Mb/s
Width                                    : 3 840 pixels
Height                                   : 2 160 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 24.000 FPS
Original frame rate                      : 23.976 (24000/1001) FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0 (Type 2)
Bit depth                                : 10 bits
Bits/(Pixel*Frame)                       : 0.215
Stream size                              : 244 MiB (99%)
Writing library                          : ATEME Titan KFE 3.7.0 (4.7.0.2002)
Color range                              : Limited
Color primaries                          : BT.2020
Transfer characteristics                 : SMPTE ST 2084
Matrix coefficients                      : BT.2020 non-constant
Mastering display color primaries        : R: x=0.680000 y=0.320000, G: x=0.265000 y=0.690000, B: x=0.150000 y=0.060000, White point: x=0.312700 y=0.329000
Mastering display luminance              : min: 0.0200 cd/m2, max: 1200.0000 cd/m2

For WebM/Matroska HDR container info as used by Youtube with VP9 for HDR you can look at MkvInfo:

+ EBML head
|+ EBML version: 1
|+ EBML read version: 1
|+ EBML maximum ID length: 4
|+ EBML maximum size length: 8
|+ Doc type: webm
|+ Doc type version: 4
|+ Doc type read version: 2
+ Segment, size 29548815
|+ Seek head (subentries will be skipped)
|+ EbmlVoid (size: 45)
|+ Segment information
| + Timecode scale: 1000000
| + Duration: 154.538s (00:02:34.538)
| + Multiplexing application: google
| + Writing application: google
|+ Segment tracks
| + A track
|  + Track number: 1 (track ID for mkvmerge & mkvextract: 0)
|  + Track UID: 11717489602804838
|  + Track type: video
|  + Default duration: 16.683ms (59.940 frames/fields per second for a video track)
|  + Codec ID: V_VP9
|  + Video track
|   + Pixel width: 1280
|   + Pixel height: 720
|   + Video colour information
|    + Colour matrix: 9
|    + Colour range: 1
|    + Colour transfer: 16
|    + Colour primaries: 9
|    + Video colour mastering metadata
|     + Max luminance: 1000
|     + Min luminance: 0.001
|     + Red colour coordinate x: 0.68
|     + Red colour coordinate y: 0.31996
|     + Green colour coordinate x: 0.26494
|     + Green colour coordinate y: 0.68996
|     + Blue colour coordinate x: 0.15
|     + Blue colour coordinate y: 0.05998
|     + White colour coordinate x: 0.3127
|     + White colour coordinate y: 0.32896
|+ Cues (subentries will be skipped)
|+ Cluster

H.264/AVC has basically identical info as HEVC but I don't know if MediaInfo supports reading that. Haven't seen anyone using it yet.

[everway9]

Hi sneaker.

Thanks very much for your super fast reply.

I'm very inexperienced with these sort of things and I don't think I fully understand.

If a files shows it to have the HEVC or AVC codec does that mean that the video definitely has HDR?


I have uploaded two screenshots from MediaInfo.

Video Codec.jpg is from a 4K video for which I do not know whether it has HDR or not. What I understand from what you said is that this video is not HDR. Is this correct?

And Video Codec 2.jpg is from a 4K video I know has HDR. So does the fact that it has the HEVC codec confirm that it is HDR? Or is the HEVC codec also used for other video files which dont have HDR?





Thanks again?

[sneaker]

If a files shows it to have the HEVC or AVC codec does that mean that the video definitely has HDR?

No.
Usually it is encoded in 10 or even 12 bit depth. And it uses BT.2020 colorspace, SMPTE ST 2084 transfer. You should see the values for min and max luminance. Max luminance for HDR is somewhere in the 1,000 to 10,000 nits (cd/m2) range. Currently mostly 1,000. SDR only 100.
The above is usually called "HDR10" or "PQ". There are additional standards incl. HLG and Dolby Vision. I haven't seen those yet.

Video Codec.jpg is from a 4K video for which I do not know whether it has HDR or not. What I understand from what you said is that this video is not HDR. Is this correct?

Yes.

And Video Codec 2.jpg is from a 4K video I know has HDR. So does the fact that it has the HEVC codec confirm that it is HDR? Or is the HEVC codec also used for other video files which dont have HDR?

It's HDR but HEVC is also used for non-HDR-videos.


P.S.: For MediaInfo I recommend "View">"Text". Then you can also copy&paste.

[everway9]

Thanks so much for all the information you have given me.

I'm beginning to understand a bit more now.

So... one of the most reliable tell tale signs that a video is in HDR would be to check the luminance is in the 1,000 to 10,000 nits range but maybe more importantly that the colour space is BT.2020?

[sneaker]

Yes, pretty much. But in the end the most reliable tool is your eye.

[everway9]

But in the end the most reliable tool is your eye.

Very true.

You have been extremely helpful and I really appreciate it.

If there was a way to vote you up or add to your reputation I would because you deserve it.

Very good forum this is with good people who like to help.

Thanks again