Re: [Gegl-developer] babl roadmap



The planned architecture as outline in babl/docs/roadmap.txt will likely collapse under its own weight.

If the devs are determined to pursue this course to the bitter end, here are some considerations regarding encoding "trc_gamma" as "double" (you really can't do this):

//begin quote from the babl roadmap

  double trc_gamma     /* makes sense to have it even if not initially
                          used */
);//end quote

ICC RGB working space profile Tone Reproduction Curve information ("TRC") can't be held in one "double" variable unless the TRC really is a true gamma TRC.

Some ICC RGB working space profiles have true gamma TRCs.

Some ICC RGB working spaces have point curve TRCs specified by varying numbers of points.

Some ICC RGB working spaces have TRCs that are specified using parametric curves, which take five parameters.

Given that not all profile TRC information can be stored in one "double" variable, you might consider removing the trc_gamma variable from "babl_define_named_rgb_space".

A proper TRC retrieving function could be written later, if/when you want to make use of the information.

With respect,
Elle Stone
--
http://ninedegreesbelow.com
Color management and free/libre photography



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