On 03/04/2010 05:58 PM, Patrick Horgan wrote:
> On 03/03/10 11:19, Jason Simanek wrote:
>> That's not true in my experience. Yes, sRGB should be as good as NOT
>> having a profile since sRGB is the ASSUMED color space on most
>> computersy. But Gimp still adds a color profile to the image: an sRGB
>> color profile. This still causes all of the color mismatch problems on
>> websites thoroughly described on the gballard.net site mentioned
>> above.
> Now I'm confused I thought gballard said the opposite.

Here's how it works:

1 Web Browsers That Don't Support Color Management
With these browsers images that do or don't include color profiles is 
irrelevant because they can't do anything with them anyway. The colors 
are just displayed as whatever RGB color space is available, most likely 
some form of unmanaged sRGB.

2 Safari (Browsers that ONLY color manage images with color profiles, 
not colors defined in HTML or CSS)
If a color profile is included with an image Safari uses color 
management to adjust the colors to the computer's display color space. 
If a color profile is not included it acts like #1. Also, as far as 
colors defined in HTML and CSS, it acts like #1.

3 Firefox 3.2+/3.5+ by default (Browsers that color manage images with 
color profiles. Images without color profiles are also managed assuming 
the sRGB color profile. PLUS: Colors defined in HTML and CSS are managed 
with assuming the sRGB color profile.

What this means for web designers/developers:

#1 isn't a problem unless you want color managed photos that look 
beautiful on your website. Otherwise, #1 is the way web browsers have 
generally worked until recently.

#2 is the wrong way to do color management on the web. It's a nice 
effort and photos certainly look beautiful, but this approach causes big 
problems for web designers that want to use images for page elements 
that are intended to exactly match and blend with colors on the web page 
that are defined in HTML or CSS. This approach forces web developers to 
NEVER include color profiles on images that are part of a website's 
design, otherwise the page elements won't match the colors defined in 
HTML/CSS. At least not in Safari. It'll look perfect everywhere else.

#3 is the right way to do color management. It makes color profiled 
photographs look as close to the creator's intentions as possible on any 
computer system that is color managed. But it also allows web designers 
to use color management to make their page element images look as good 
as intended while still matching the HTML/CSS colors that are also part 
of the web page.

Thanks to browser type #2 I can only use color profiles on images that 
are not intended to be a part of the web site's design. If I do include 
color profiles on those images, every time I bring up the site in Safari 
it will look like my page elements don't match the flat colors defined 
in my site's HTML/CSS.

So the color mismatch I'm concerned about really only happens in Safari, 
but mismatches like that are not acceptable.

Did that resolve your confusion? Or just add to it?

-Jason Simanek
Gimp-developer mailing list

Reply via email to