Every time a new technology is invented it presents both
benefits and problems to the adopters. This is not any different in the case of
wide color gamut (ninety-plus percent of Adobe RGB) monitors. As more and more
manufacturers join the elite group of EIZO and NEC an increasing number of
people face the question: is my operating system and applications are mature
enough to handle these "Adobe RGB" monitors? The answer is not a clear "yes".
Fortunately almost all of the applications in one's photo editing and pringring
workflow are color management aware, thus they are able to handle these monitors
corretly. But what about the Web? Photographers need a web site these days to
market their work, and it is really important that clients see exactly what the
photographer intented.
Back In 1996, Hewlett-Packard and Microsoft proposed
a standard, called sRGB for specifying and handling color in operating
systems and on the web. You can read the
paper here. Up until lately, almost
everybody ignored this standard, as the majority of the monitors were only
able to display colors residing in the sRGB gamut. The invent of wide gamut
monitors (such as the CG series from EIZO) with the ability to display
95-100% of the much bigger Adobe RGB color space, made evident the lack
of color
management support in browsers. When I first booted Windows XP and subsequently
Mac OS X 10.5 on my EIZO CG241W, all the web pages looked horrible - with
over-saturated colors.
In this article I'll show how the currently available
web browsers and active componenst support color management.
State of affairs
Part 3 of the aforementioned sRGB standard describes
how one should implement a color managed web browser. The essence of this
is the following:
- All elements (images, text, background) should be in the sRGB color
space. Text and background are assumed to be in sRGB (the proposed
style sheet extension is not implemented even in color managed browsers).
- If an image has no associated ICC profile, it is assumed to be in sRGB.
- If an image has an associated ICC profile, it is converted to sRGB.
- The entire page (which is in sRGB after the image conversion) should
be converted to the monitor profile, if there's one associated with the monitor.
If the user's machine has no monitor profile, the sRGB page is displayed
preserving color numbers (which is equivalent to associating the monitor
color profile with it).
How does current browsers implement this simple standard?
Ironically, even after Microsoft took a great share in
creating the sRGB standard, Internet Explorer up to version 8
does not implement color management at all. Maybe because it would slow down
page display by 10-15%, or just based on the fact that the majority of Windows
users does not have a clue what this stuff is. Anyway, it should be an option
which is turned off by default.
Opera took the IE approach - no color management support.
Apple's Safari 3 and 4 is a mixed bag. It
was the first browser that were advertised as "color managed", but in truth
it's implementation
is quite inconsistent and presents more problems that it solves.
Yes, it
treats images with embedded ICC profiles correctly - converting them to
the display profile. But everyting else on the page - static elements like
text and background as
well as images with no associated profile - are assumed to be in the display
color space. So on a wide-gamut monitor text and some images look horrible,
while some other images are good. And if someone designs a web page with
properly color managed images, there's a mismatch
between the image's color managed background and the page's unmagaged background.
All in all, this browser only works if one uses ICC-tagged Adobe RGB images
on a web page which is displayed on an sRGB monitor. In addition to this
pretty weird behavior, color management cannot be turned off with
a configuration option. I don't know what Apple engineers had in mind...
The only correct implementation is in Firefox
3 and 3.5. It does exactly what Part 3 of the sRGB spec says. Well
done! Moreover, color management is turned off by default on version 3 so
non-color-management-aware users will also get what they expect. Unfortunately
the default behavior in 3.5 is the same ill-behaved approach that Safari have.
If you are interested how to enable color mangement in Firefox, open up version
3 or later and go to this page.
Flash and Silverlight
Up until recently, active components were also lacking color
management. This is slightly changed with version 10 of Adobe's Flash player.
Flash 10 in conjuction with ActiveScript 3 fully supports color managed display
of images. But only with ActionScript 3. Gallery software written
in ActionScript 2 will need some hacks. Unfortunately, Flash 10 is unable
to detect the color management support in its host browser, which will cause
some headache for web developers and inconvenience for users.
Silverlight 2 joins the happy family of products that does
not know about the existence of color management.
This site
Having seen the diverse landscape of web technologies,
one could wonder how we implemented color managed browsing support on this
site.
All the images here are converted to sRGB as part of
the web processing workflow. They are also tagged with sRGB. Portfolio
galleries are Flash 10 based. Depending
on your browser, however, we do things differently:
- In case of any browser ofher than Safari 3+ and Firefox 3+: we turn off
color management in galleries. This presents a consistent, but non-color-managed
experience.
- In case of Safari 3+: we turn on color management in galleries. This
is consistent with the otherwise inconsistent behavior of Safari 3. So
all the images and galleries are displayed consistently color-managed.
Text and backgrounds fall where they may.
- In case of Firefox 3+: we turn on color management in galleries. Firefox
3+ does not allow a web pages to query the state of the browser's color
management options, and even Flash 10 fails to detect it. So we encourage
you to turn this on. Details on how you could do it
are here.
Of course, these things only apply to you if you have a calibrated and
profiled monitor. Otherwise everything will be displayed without color
management.
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