J. King Log

Over the last few days I have been, for reasons I myself am not entirely sure of, researching free graphic editors. I don't generally do much graphic editing; I just don't have the knack for visual stuff. However, I do occasionally do some touch-ups, croppings and whatnot.

If there's one thing that can be said about me, it's that I have an almost zealous love for good, free, public technologies. Whether it be HTML, CSS, Atom, Jabber, Vorbis, FLAC, SVG (although I hesitate to call SVG good) or any number of other wonderful little goodies, I'll latch on and probably never let go. Thus is the case with PNG.

Adoption of PNG over the last decade of its existence has been quick in some circles and torturously slow in others; most notably, Internet Explorer gained a suitably complete (though still buggy) implementation just last October. Generally, though, Web browsers today have no major troubles with PNG. The picture, on the other hand, is a little different when it comes to editors.

One of the more useful and famous features of PNG is what is called alpha blending: any pixel in a true-colour image can be partially (or completely) transparent. This becomes especially useful on the Web, when it's advantageous for images to be able to blend in with arbitrary backgrounds. Less known, however, is the fact that a very similar feature exists for paletted images: any colour in an image's palette can have a level of transparency associated with it. Instead of, say, having a monochrome image with only black and transparent, you could have four blacks, one of them opaque, another 25% transparent, a third half-transparent and a fourth mostly transparent so that the edges of the visible pixels are smoothed out. Thus, you have all the size advantages of GIF without the jagged edges.

Unfortunately only one image editor I know of, Adobe (formerly Macromedia) Fireworks, implements this immensely useful feature. Having tried over two dozen free and freeware editors for Windows (yes, including The GIMP) over the past few days, I found not a single one that will produce proper paletted images, and few that will even read them. If one doesn't have the money for Fireworks or is using Linux, the only option appears to be pngquant, which doesn't exactly give one easy control over which colours will end up in the palette.

It seems strange to me that with so many obvious benefits this feature isn't given more attention and love. I guess I shouldn't be too surprised, though: PNG is only ten years old.