[robski]

It would be interesting to know if Safari supplies it own colour management engine such as CMM to deal with the ICC profiles or uses Windows OS colour management ICM or maybe it supplies the Mac Colorsync engine.

Anyway I've have extracted some relevant parts from an Adobe technical document you may find interesting on colour spaces.

sRGB

Hewlett-Packard and Microsoft designed sRGB as a standardized RGB space for consumer-level
digital cameras, scanners, and printers. The goal was that users of these devices wouldn’t require
any color management knowledge to produce acceptable results. Such devices would assume the
color space is sRGB, making the reproduction process within applications that didn’t use color
management simple.

sRGB is derived from HDTV standards, so nearly all CRT and LCD displays can reasonably
produce sRGB if properly calibrated. Even uncalibrated, such devices often produce adequate
color from images in sRGB.

Since few web browsers are ICC aware, sRGB is currently an ideal color space for images destined
for the Internet. Of all the RGB working spaces installed with Adobe applications, sRGB has the
smallest gamut. The gamma encoding is 2.2. However, sRGB’s gamut is a limitation for more
demanding output, such as a printing press or many of the ink jet and photo printers so commonly
used today.

Apple RGB

Apple RGB is a legacy working space based on the original Apple 13" Trinitron monitor. The
gamut isn’t much larger than sRGB and the gamma encoding is 1.8. Early users of Macintosh®
computers working with products such as Photoshop and Adobe® Illustrator® used Apple RGB
as their working space prior to the introduction of additional working spaces in these products.
Unless you need to work with documents created from very old versions of Photoshop (4.0 or
earlier), there is little reason to consider Apple RGB.

Adobe RGB (1998)

This working space has a significantly larger gamut than any of the working spaces discussed so
far. Adobe RGB (1998) uses 2.2 gamma encoding. This working space is much better for those
who will output their files to a printing press, since the gamut allows all colors in Specifications
for Web Offset Publications (SWOP) CMYK to be fully contained. One issue with a gamut this
large is it is larger than the gamut of nearly all displays. Saturated colors that may exist in Adobe
RGB (1998) could be outside the display gamut and thus not visible. You might be editing colors
you can’t see. This fact is true of all working spaces that exceed a display gamut. Note that a few
high-end displays providing an extended gamut matching Adobe RGB are now available, but at
a very high price. Unless you know you have such a display, you are probably working within
the gamut restrictions of sRGB when viewing your images. The advantages and disadvantages of
wide gamut spaces are below in more detail.


Limitations of working spaces

As discussed, the gamut of a working space in comparison with the gamut of your display should
be considered. However, just because a working space gamut exceeds the display gamut doesn’t
mean a color document will exceed the gamut of either. Images have a color gamut as well. You
might photograph a scene of very pastel colors such as a white dog on snow. You could encode
that image into ProPhoto RGB, but a huge portion of that working space gamut isn’t used. The
scene gamut might fit better in Adobe RGB (1998) or even sRGB. You need to be aware of the
working space gamut, the scene gamut, as well as the gamut of any output device you may use.
When you work with 24-bit images, all color and tone is defined in three 8-bit color channels. When
you work with wide gamut working spaces, the same bits need to be spread farther apart over the
entire color space. Consider this spreading of a finite number of bits as follows: Imagine you have
a half-inflated balloon that has 16.7 million dots evenly spaced over its surface. Now you blow
up the balloon to twice its original size. Each dot is spread farther apart. When you work with
8-bit-per-channel files, you create this effect when you encode the bits into a progressively larger
gamut working spaces. In such situations, it is possible that editing images will produce banding
(aliasing). For this reason, should you decide to use a wide gamut working space—for example,
something wider than Adobe RGB (1998)—you should attempt to encode the data in 16-bit color.
Many capture devices produce more than 8-bits per color and allow you to retain this extra data
to use in Photoshop. While the file size will be twice as big and image processing will take longer,
you can’t be too careful with your data. You may also wish to use 16-bit data with smaller gamut
color spaces.