On Mon, Oct 13, 2014 at 8:19 PM, Elle Stone <ellestone@xxxxxxxxxxxxxxxxxxxx> wrote: > The "sRGB as PCS" architecture outline in babl/docs/roadmap.txt will likely > collapse under its own weight. The roadmap should be amended to reflect a > more accurate assessment of the amount of work the planned architecture will > entail. > > The babl roadmap says: > > "Babl currently only supports formats using the sRGB primaries, quite a few > editing operations including gamma adjustments and multiply compositing > relies on the chromaticities of the space used, permitting at least linear > formats with other chromaticities is highly desirable" > > As the purpose of the roadmap seems to be guiding future development, the > list of editing operations that rely on the chromaticities of the RGB > working space needs to be expanded. The following list is not complete, but > it's a start: The place for this would be in the GIMP wiki; where the state of migration from old type gimp plug-ins to GEGL ops, as well as other tracking state of ops are maintained. http://wiki.gimp.org/wiki/Hacking:Porting_filters_to_GEGL > The roadmap says "permitting at least linear formats with other > chromaticities is highly desirable". It is unclear why "permitting" should > be limited to "linear formats". All of the operations listed above depend on > the working space chromaticities, regardless of whether the RGB values are > linear or perceptually uniform. This has to do with which capabilities one chooses to implement early, since it would bring a functional system, the non sRGB TRC are nice to have but not as fundamental as custom chromaticities. Not having custom TRCs for custom formats; means that those formats would be using the sRGB TRC until such support would be added. > Indeed, some (and probably many) operations, that work just fine on linear > unbounded sRGB values, are *very* dependent on the chromaticities when > performed on perceptually uniform RGB values (for example drawing a > gradient). > > Someone should check all editing operations for perceptually encoded RGB to > figure out which operations depend on the chromaticities, and then add these > operations to the list of operations that need to be special-cased in the > planned "sRGB as PCS" architecture. The per-op working pixel representation are part of GEGLs design, thus it isn't really special casing - but specifying. /Ø _______________________________________________ gegl-developer-list mailing list List address: gegl-developer-list@xxxxxxxxx List membership: https://mail.gnome.org/mailman/listinfo/gegl-developer-list
