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Something both Safari and Firefox 3.1 have by default
Here is the test

Ok, here is the home page of the gimp-cmyk plugin: http://www.blackfiveservices.co.uk/separate.shtml. Here is his disclaimer:

One thing preventing The GIMP from being useful in a pre-press environment is the lack of support for the CMYK colour-space. This plug-in goes some small way towards rectifying the situation, using a trick with layers to fake CMYK support. The plugin is unfinished, but usable for its primary purpose, and since I'm unlikely to have time to develop it further in the near future, I'm releasing it as is.

Now here is a link to an article discussing GIMP, Pantone and CMYK: http://software.newsforge.com/print.pl?sid=05/10/2 5/153221. Interesting, and it looks like the legal issues around Pantone's color lists are pretty fuzzy.

There's no issue whatsoever of "accuracy" in producing nominal colorspace conversions, but if your needs include decomposing an image to a proprietary profile such as Pantone[...]

Well, for pre-press work the accuracy of converting to and from any profile is pretty much everything (btw, the word "profile" in color management deals with devices and not color lists, and it's a standard (ref: http://www.color.org/profile.html). It's true that converting RGB to CMYK is "a simple matter of mathematics" in that it's "just" a transformation, but the difficulty lies in that different devices and colorspaces have diffferent gamuts, and the magic lies in how you deal with the additional or missing information. I don't believe there is a standard for these transformations, and in fact if you perform the same transformation on the same image with different engines you will get different results (I had to compare 4 leading products for a client last year).

In a nutshell, it appears that CMYK support for GIMP is fine if you don't care about color accuracy, but since pre-press DOES care about accuracy GIMP is unsuitable.

It also passes the International Color Consortium ICC version 4 test again, which also worked on Safari 1.3. Prior to Safari 2.0.2, Safari 2.x only passed ICC version 2 test.

Javascript speed seems a hair faster and gives Opera a good run.

Javascript benchmark

Mac Mini 1.25 GHz w/ 512MB RAM
OS___________Version _______Trial 1_________Trial 2
Mac OSX 10.3.8 Safari v1.2.4___ 85.28 seconds___86.28 seconds
Mac OSX 10.3.9 Safari v1.3____ 10.97 seconds___10.39 seconds
Mac OSX 10.4.0 Safari v2.0____ 09.48 seconds___09.30 seconds
Mac OSX 10.4.2 Safari v2.0.1___ 09.41 seconds___09.07 seconds
Mac OSX 10.4.3 Safari v2.0.2___ 08.41 seconds___08.54 seconds

iMac G5 1.8 GHz w/1GB RAM
OS___________Version _________________Trial 1_________Trial 2
Mac OSX 10.4.3 Opera 8.5__________ 07.45 seconds___07.39 seconds
Mac OSX 10.4.3 Safari 2.0.2_________ 08.51 seconds___08.79 seconds

Mac OSX 10.4.2 Opera 8.5__________ 07.31 seconds___07.88 seconds
Mac OSX 10.4.2 Safari 2.0.1_________ 09.02 seconds___09.12 seconds
Mac OSX 10.4.2 Camino 0.8.4_______ 15.13 seconds___15.33 seconds
Mac OSX 10.4.2 Firefox 1.0.7________ 21.04 seconds___20.84 seconds
Mac OSX 10.4.2 Internet Explorer 5.2.3 40.87 seconds___36.94 seconds
Mac OSX 10.4.2 Mozilla 1.7.12_______ 44.11 seconds___43.54 seconds

Mail.app 2.0.5 fixes the annoying problem with replicating new messages twice or thrice for IMAP email.

Get Info and Finder now shows Architecture the application binary runs on. Guess this will help with the transition to x86 to identify which applications are PowerPC only or Universal. I assume people aren't going to be writing exclusively for Intel X86 Mac OS X applications for a long time.

The bad:

Quartz 2D Extreme is still not part of Tiger. Hopefully it will make it in Leopard.

"Disables Quartz 2D Extreme--Quartz 2D Extreme is not a supported feature in Tiger, and re-enabling it may lead to video redraw issues or kernel panics."

I stand by my comment, I'm a researcher in image analysis, I do colour processing all the time, I've never used Pantone in my work and never have I seen any other researcher use them, because it's not a published open standard. Pantone solves one problem very well through the sale of proprietary standards and products, but it is not the scientific reference to colour processing. If you want to define a particular colour unambiguously and for all times, the only currently accepted scientific way is to use one of the CIE colour spaces.

Furthermore I have a hard time believing that Pantone it *the* standard for prepress printing. There is such a thing as the ICC, the International Colour Consortium, which would have a better claim to that. There are other systems used in pre-print, such as Focoltone and Trumatch among others. Pantone is a widespread and easy to use system to specify colour (use Pantone colour #285) but it doesn't solve all the problems associated with colours.

You can obtain the specs on ICC profiling at http://www.color.org/ but the algorithms are proprietary...

Interestingly enough, Silicon Graphics is a member of ICC, and perhaps an inquiry can be made as to a open/closed-source Linux/*BSD port of their color calibration software (BTW - Photoshop 2.5 was excellent on Irix).

However, as both M$ and Apple are also members of ICC, I'm sure both would object to any OSS port :-/

~AC

There are basically two types of color matching that are relevant. The first is Pantone spot colors, and the second is ICC. The latter is generally what you'd use when preparing photos and related images for CMYK offset printing. ICC is gaining ground, and is used as the color matching standard in such emerging technologies as SVG.

Pantone is basically a named collection of colors. The cool thing about Pantone is that you can communicate Pantone colors to professional printers, and they know how to match it. Let's say for example that you're doing a business card, and you want your logo to be in black and a nice deep blue. By specifying Pantone 280, you can be assured that the printers will produce the same nice deep blue that you intended. Incidentally, it's not hard to find a Pantone palette for Gimp if you're skilled at Web searching.

Pantone colors are far less useful when dealing with natural images. The Pantone palette is only a few thousand colors, while the standard for scanned images is sixteen million. These are all the colors between "nice deep blue" and "slightly deeper blue than that". That's where ICC comes in.

ICC basically specifies a transformation from a source color space (say, a calibrated RGB such as sRGB) to a destination color space (say, CMYK values for your particular printing press). In theory, this allows exact color matches between scanned, displayed, and printed images, but in practice things are a lot more complicated because (a) people don't perceive color the same way from an emissive display such as a CRT and reflected color from paper, and (b) not all devices can reproduce the same range of colors. Category (b) is especially tricky because the only way to ensure an exact color match is to use a lowest-common-denominator set of colors. As you can imagine, that's not a good idea. It doesn't look very good. In any case, ICC goes at least partway to solving these things.

Now we get to the patent problem. It appears that Electronics for Imaging has some patents that cover the generic idea of colorimetric matching between scan, display, and print. These patents have recently been upheld in court, so they'd appear to be pretty strong. I don't see a way around them.

As far as I know, these patents only apply in the United States. There is some very interesting development of color management code going on outside the US. Perhaps in 2003, when the most important of the EFI patents expires, this means that color management will be free for all to use.

Hope this clears things up.