Interaction between "-n" flag and HDR video fields

[shermanhewitt]

Hello! I'm using the Exiftool CLI to get metadata from an HDR video. When I run the following command...


exiftool -G fastflix-2160p.mp4


... the HDR-related fields appear like so:

Code Select Expand

[QuickTime]     Color Primaries                 : BT.2020, BT.2100
[QuickTime]     Transfer Characteristics        : SMPTE ST 2084, ITU BT.2100 PQ
[QuickTime]     Matrix Coefficients             : BT.2020 non-constant luminance, BT.2100 YCbCr

This makes sense to me! However, when I run the following command...


exiftool -G -n fastflix-2160p.mp4


... the same HDR-related fields now appear like so:

Code Select Expand

[QuickTime]     Color Primaries                 : 9
[QuickTime]     Transfer Characteristics        : 16
[QuickTime]     Matrix Coefficients             : 9

Why would this be the case? I ultimately need to parse these fields to determine if a video is an HDR video. At the same time, my use case requires the "-n" flag in order to extract other, non-HDR-related fields.

My Exiftool version is 12.70.

[Phil Harvey]

See the QuickTime ColorRep tags for details about the numerical values of these tags.

If you need the numerical values of some tags but not others, you can either specify the tag names on the command line and add "#" to the tag names to get numberical values, or use the -j or -X outputs with -l to get both numerical and converted values.

- Phil

[StarGeek]

This wouldn't have been obvious since you are reading tags instead of writing them, but you can read the details under FAQ #6, I get 'Can't convert TAG (not in PrintConv)' errors when writing a tag

[shermanhewitt]

See the QuickTime ColorRep tags for details about the numerical values of these tags.

Ah, this is perfect. Thank you so much!