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.

> Author:  Omari Stephens <> 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.

There should be a "color tag" status somewhere for an image.

> 2) When an image is opened _with_ an associated color profile, the user will 
> have the
> following options:

> b) Convert the image to some other explicit profile

Same comment as above.

> 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).

d) Have an option to write the file without an embedded profile. This is an 
option in regard to dealing with other applications, for instance sending 
or profiling files to a particular device.

> 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

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.

Graeme Gill.
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