On 02/08/2010 01:39 AM, Graeme Gill wrote: > Omari Stephens wrote: >> Obviously, options for both of these things are "prompt the user." It seems like there >> should be better alternatives, but I'm not sure what they might be. guiguru? others? > > You're better having a set of defaults that the user can configure, > so they aren't constantly hassled by prompts. The configuration can > have options such as "prompt me" for certain combinations. Yes. By "prompt the user" I meant something similar to the current behavior when an image is tagged with a color profile other than the working space profile; the options are: 1) Do nothing 2) Convert to working space profile 3) Prompt the user I was hoping someone would come up with a better convention, but since that doesn't seem to be happening, I will rev the spec and mention this UX paradigm explicitly, with the hope that it will be improved upon in a later revision. >> Author: Omari Stephens<xsdg@xxxxxxxx> Version: 1 Date: 3 February 2010 > >> 1) When an image is opened with no associated color profile, we assume that it is >> encoded in sRGB space. > >> c) Convert the image from >> the implicit profile to some explicit profile (AdobeRGB, ProPhotoRGB, sRGB, etc.) > > Not a good idea. There are losses in every color conversion. Ideally you want to > keep an image in its original format, unless the user explicitly decides to > convert to another colorspace. Input is not the place to do this. > > So the application (GIMP) should have a transformation step available to: > > 1) Convert from one colorspace to another. If an image has no tag, > then both profiles would need to be specified. > > 2) Assign a profile to the image. This would set or override a tag. > > One idea to consider is the possibility of a "weak color tag". This > is for a image that is to be considered un-tagged, but has a profile > to specify the source colorspace for the purposes of display, and conversion. Your "weak color tag" is exactly what I meant by an "implicit sRGB profile". My judgment was that it wouldn't be useful to have a "weak" tag that wasn't sRGB — anything else should be explicit and embedded. > There should be a "color tag" status somewhere for an image. Because the only implicit color tag is sRGB, the absence of an icc-profile parasite (or an empty one) can be considered equivalent to the implicit sRGB tag. >> 4) When an image with an explicit profile is exported >> a) It will be tagged with that >> profile in whatever way is appropriate for the file format. >> b) If this is an sRGB PNG, >> we need to decide between an sRGB chunk and sRGB profile. See later discussion. >> c) If the file format has no way to embed color profile information, (FIXME!) > > For c), have the option to covert to a particular colorspace (ie. sRGB). Cool. Any thoughts from other people? > d) Have an option to write the file without an embedded profile. This is an important > option in regard to dealing with other applications, for instance sending calibration > or profiling files to a particular device. I was thinking a tiny bit about this, but hadn't come up with anything conclusive. I'll probably implement something trivial where you can select a menu item to dump the icc-profile. >> 5) When an image with an implicit profile is exported a) The image is saved with no >> color profile information. For PNG, this means no sRGB chunk and also no iCCP chunk. > > You could really have the same options as 4, although you might default them > differently. Hmm; good point. Will think about that. > There are many possible ways of dealing with this issue. The important things as > I see them are 1) Allow defaulting to logical and useful workflows 2) Allow > flexibility to accommodate particular needs. Yup. Thanks for thinking about this. --xsdg _______________________________________________ Gimp-developer mailing list Gimp-developer@xxxxxxxxxxxxxxxxxxxxxx https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
