Optional vs Required

(Scott Dyer) #1

On the first call it was stated that the specification should not contain optional parts. A “common LUT format” where implementations are not required to implement support for all parts of the format loses its commonality.

I can only find one instance where something is specifically labeled as an extension and is not required. Appendix D, bullet point #1 says, "IndexMaps with dim > 2 are an extension and are not required".

Are there other features that are specifically called out as being optional?

Notice of Meeting - CLF Spec / Code Review - 1/17/19 9am pst
(Nick Shaw) #2

“IndexMaps with dim >2” is certainly the big one.

InputDescriptor (optional)
Comment field describing the intended source code values of the ProcessList.

OutputDescriptor (optional)
Comment field describing the intended output target of the ProcessList (e.g., target display).

Not a “feature” in the same way, but I would like these two to be required as well. Any LUT needs correctly formatted input to work correctly, and for the output to be appropriately handled. The number of times I see people say “I like the look of the ALEXA LUT, so I use it with my camera X”.

And if rather than being free text comment fields, there were defined strings to at least specify the ACES colour spaces, that would open up the possibility of automatic pipeline configuration, and reduce the chance of errors.