Re: [Gimp-developer] New Image/Color Management option

[Michael Natterer <mitch gimp org>]

On Sun, 2016-05-15 at 08:14 -0400, Elle Stone wrote:
> On 05/12/2016 03:56 PM, Michael Natterer wrote:
> > On Thu, 2016-05-12 at 08:46 -0400, Elle Stone wrote:
> > > > There is a new "Image/Color Management" option to "Enable Color
> > > > Management". The option is checked by default. For sRGB images,
> > > > checking
> > > > or unchecking the option doesn't seem to make any difference.
> > Exactly, even without a profile, pixels have some meaning. And
> > in GIMP, the "default" meaning is sRGB.
> Frankly I don't see the utility of this new option. Users who don't
> want 
> to deal with the complexities of ICC profile color management
> already 
> have the option to only edit sRGB images.

True, but they need to know that what they want is equivalent
to using sRGB. They want a "don't bother me with any of this"
setting because they really don't know or don't want to know
any of it.

> But if there really is a defensible use case, here are two concrete 
> suggestions:
>
> 1. Move this new option down to the group of options below and
> separated 
> from the two normal Color Management options.

Do you mean in the new submenu? IMO a global "enable" switch
clearly belongs at the beginning of a section.

> 2. Relabel the option as "Assume this image is an sRGB image".

That's exactly what is confusing to them :) "What is sRGB again?"

> Here is why I'm making these two suggestions:
>
> GIMP menu items and help hover tips shouldn't misinform GIMP users,
> but 
> instead should tell GIMP users the truth and also help to educate
> them.

I agree, and propose to have tooltips that disabling is the same
as using the built-in sRGB profiles.

> In an ICC profile color-managed editing application, pixels are 
> literally meaningless without knowing which ICC profile should be
> used 
> to give the channel values meaning. You can't change the very basis
> of 
> ICC profile color management by arbitrarily deciding that for GIMP
> "no 
> profile" actually means "sRGB". Because it doesn't. And pretending
> that 
> it does will mislead GIMP users.

But it does, it really does in the code. no profile == sRGB.

> The global switch in "Preferences/Color Management" to set the Image 
> display mode to "No color management" actually does disable color 
> management. This means that the image RGB channel values are sent 
> directly to the screen. This is the functional equivalent of
> assigning 
> the user's chosen monitor profile to all open images.

That switch is *only* for display color management, If you
disable it, things are still properly converted if you
copy pixels between images.

> Unchecking the pre-checked box in the "Images/Color Management" menu 
> that says "Enable Color Management" sounds like it should do the
> exact 
> same thing as going into Preferences and setting the Image display
> mode 
> to "No color management". But what unchecking "Images/Color
> Management" 
> actually does is *assume* the image is an sRGB image, even if the
> image 
> already has an ICC profile that's not the sRGB profile. This
> assumption 
> only produces the same result as choosing "No color management" in 
> Preferences if the user has also chosen sRGB as their monitor profile
> in 
> "Preferences/Color Management".

I just reorganized the prefs page and it should now be clearer that it 
is meant for display settings only.

> The truthful and less confusing verbiage for this prechecked 
> "Images/Color Management/Enable Color Management" option would be 
> "Images/Color Management/Assume this image is an sRGB image".

We can have a tooltip saying so, but using that suggested wording
defeats the "don't bother me, I don't want to understand it"
purpose of the setting.

> Also, the position of the new option gives it "mouse scrolling" and 
> "visual" importance. The user has to read and then scroll past this
> new 
> option to get to the more normal Color Management options to assign
> or 
> convert to a new ICC profile.

So the new option is at the right place. Sorry, but I'm 100%
convinced that the vast majority of users has no clue whatsoever
about color management. Heck they can't even distinguish pixels
from DPI. A simple was to turn it off is IMO exectly what's needed.

> This prominent placement of the new option in the "Image/Color 
> Management" menu makes it seem like a normal thing to do while
> editing 
> an image is to disable Color Management, which of course isn't at
> all 
> what this option really does.

It switches to default things and that's all it can do, there
are no pixels without meaning ever since we made color management
omnipresent in GIMP.

> So again, if this new option really does have some utility (and again
> I 
> can't see that it does), then it would be better to do the following:
>
> 1. Move this new option down to the group of options below and
> separated 
> from the two normal Color Management options.

Sorry, nope, unless you convince me with some better arguments :)

> 2. Relabel the option as "Assume this image is an sRGB image".

That definitely not, but I will immediately add tooltips saying that
it is the same as choosing sRGB.

Regards,
--Mitch