Re: [Cellar] FFV1 Version 4

["Peter B." <[e-mail]>]

On 01/07/2016 07:34 PM, Jerome Martinez wrote:
> PS: just to be clear, when you speak about "logarithmic", you speak
> about DPX transfer characteristic value 3 "Logarithmic [to be defined
> by SMPTE I23 Technology Committee,
> sub-group on “Transfer Characteristics”]", right?
> (note: the "to be defined" is in the spec from 2003 as well from the
> spec from 2014 :), without further description)

Well, personally I'd say I'm speaking about "color values that are
non-linear".
In practice, I've only encountered "quasi-log(TM)" (aka "logarithmic) -
and DPX being the most popular case for these non-linear color values.

So in order to stick to real-world use-cases I mentioned
"logarithmic-DPX-to-FFV1-and-back".
Could also be "Non-linear-Foo-to-FFV1-and-back" ;)


Maybe it would make sense to collect what kind of non-linear color
interpretations appear in the real world and derive some way of handling
them.
At least the most prominent ones?

For example, like the ones Reto mentioned:
// -------------------
- log RGB (= "quasi-log", sometimes also called "pseudo-log") encodings:
FilmStream (log60), ARRI log F, Panalog, Sony-log (= S-log), REDLOG, SI
log90
- log neg encodings: Cineon printing density (CPD), "DPX", ARRI log C
// -------------------


Regards,
Pb


PS: Maybe something like a CLUT could be stored as a self-contained way
of interpreting the non-linearity of the color values?