Safari, Firefox charge towards a more colourful Web

Apple's Safari browser is able to display richer, more deeper colours than either Internet Explorer or Opera -- but Firefox is expected to catch up in the next month.

Unlike the prevailing browsers on the Internet -- Microsoft's Internet Explorer and Mozilla's Firefox -- the Apple browser supports different ways of encoding images that can mean richer, deeper colours. With the beta version of Safari now on Windows, Mac OS X users aren't the only ones who'll be able to see the difference.

However, Apple won't keep that edge for long. Mozilla's forthcoming Firefox 3 browser, due to ship in beta form this July, likely will include support for richer colour, said Vlad Vukicevic, a technical leader at Mozilla and a photo enthusiast.

Together, the moves could help boost the Internet beyond the orbit of the sRGB color scheme, a broadly supported but limited standard initially introduced by Hewlett-Packard and Microsoft. But it's not likely that Web photography will achieve sRGB escape velocity until the dominant Internet Explorer also follows suit.

sRGB is fine for most people today, said Brad Hinkel, author of Color Management in Digital Photography and more recently a Microsoft project leader. But it doesn't encompass the full gamut of colours that the human eye can perceive or that can be displayed on the latest monitors.

"I've seen them. They're knock your socks off, intensely amazing -- beautiful, vibrantly rich colours," Hinkel said. "Getting colour management into Safari, into the browser and on the Internet is a great thing."

sRGB alternatives
Although the vast majority of images on the Web are encoded with sRGB, alternatives such as Adobe RGB, the European Color Intiaitive's ECI RGB and Microsoft's scRGB can display a broader palette of colours.

For now, there's little point employing the more sophisticated colour schemes on the Web. IE, Firefox and Opera can't display them, and worse, Adobe RGB images, for example, typically look worse than sRGB on the Web. That's because the non-Safari browsers, incorrectly interpreting an Adobe RGB image as sRGB, drain the images of some of their colour.

Not so with Safari. Apple machines are in widespread use among graphics professionals, and the operating system supports colour encoding schemes that are called profiles and are standardized by a group called the International Colour Consortium (ICC). Safari checks to see whether an image is tagged with a particular ICC colour profile and displays it accordingly, tuned to work with the user's monitor.

While average Web surfers aren't likely to notice much of a difference, some professional photographers do care about the issue. For example, those selling images over the Web as stock art want them to look as good as possible, but they often encode their images as sRGB to make them appear better on the screens of potential purchasers.

People can see whether their browser properly supports colour profiles by visiting an ICC Web page that shows a specially constructed image. With colour support, the image appears to be a desert formation against a blue sky; without colour support, it's a checkerboard of garishly distorted hues.

Colour on computers is a complicated business, given the wide variety and near-infinite combinations of video cards, displays, printers, ink and cameras. ICC profiles can bring order to some of the chaos while preserving a bit more of the richness of colour that human eyes can perceive.

Safari's competition isn't standing still. Microsoft wouldn't comment on future colour-support plans for this article, but the company has sunk a lot of time and money into the colour problem.

Microsoft developed scRGB, a wide-gamut colour space that's now an international standard. For example, where sRGB devotes 8 bits of data to describing the red, green and blue colour components for each pixel of an image, scRGB can devote 16 or 32 bits per component and describe the colours with more flexible floating-point numerals instead of just integers.

In addition, Microsoft is pushing a file format called HD Photo that it hopes will become a replacement for the ubiquitous JPEG. HD Photo -- support for which is built into Vista under the format's previous name, Windows Media Photo -- uses the scRGB colour space. Supporting other colour spaces in IE is a logical extension of promoting HD Photo.

The open-source Mozilla project is less tight-lipped about its plans for colour profile support. "I'd love to see it in Firefox 3, and we're working to get it there," Vukicevic said.

It's not certain that Firefox 3, code-named Gran Paradiso, will support ICC colour profiles. But there is a patch under development and testing right now, Vukicevic said, and the goal is to include it. If it does ship, though, colour management likely will be disabled by default.

"We're hoping to get the feature in for the first beta. At that point, we'll look at the feedback and decide whether to turn it on or off," Vukicevic said. For those who enable colour management but who haven't calibrated their monitors to display standard colours, images will look different. And it's a toss-up whether they'll look better or worse, he said.

Another factor is performance. Enabling colour support degrades Web page display "a few percent" for normal browsing, he said.

Firefox runs on multiple operating systems, including Windows, Mac OS X and Linux. To bring colour support to all those foundations, Firefox uses an open-source colour management engine called Little CMS that can translate from one colour space, such as the one a photo uses, to another, such as the one a monitor uses.

ICC colour support has been a longstanding feature request in Mozilla; the bug listing for the project initially was filed in 1999. It's been a personal issue for Vukicevic, too: he's a photographer as well as a programmer.

"There's a bunch of us at Mozilla who are amateur photographers," Vukicevic said, and they've "been clamoring for ICC support for quite a while now."