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IE PNG hack

Try this fix. It uses a CSS and some javascript to fix IE's handling of PNG images.

It sucks that one has to play these shennanigans to fix such basic functionality. It also begs the question if javascript can fix IE's mishandling... what's the hold up from Microsoft themselves?

Here's a hack that will make IE render transparent/translucent PNG files.
http://www.mongus.net/pngInfo/

• Bright (download) is the best non-dithering quantiser in the whole world, and reasonably fast, too; based on dlquant
• pngrewrite sorts the palette
• pngcrush removes junk chunks, fixes Photoshop's gamma bug and tries many filters to find a smaller filesize
• OptiPNG is similar to pngcrush, but executes much faster
• pngout uses an alternative deflate, yields sometimes even smaller filesizes
• tweakpng manipulates chunks comfortably with a GUI
• pngquant quantises PNG24 with alpha transparency to PNG8 with transparent palettes, the result is alas mostly ugly

sleightplus demonstrates how to overcome IE's rendering bugs without polluting your markup or styles; no silly style inlining required, either. Use PNG images or backgrounds all the way they were intended.

Predecessors with only support for foreground images: Youngpup sleight, WebFX PNG behavior, mongus pngInfo, Bob Osola. PNGHack, a server side solution, is doomed to fail because of dysfunctional browser sniffing.

If that was useful for you, and you are a C hacker, I have a plea. Take the dlquant sourcecode (see above) and massage it so it works with PNG instead of the archaic PPM. I want a functional Bright clone for Linux that takes a true colour PNG and outputs a paletted PNG. Can you do that?

Yeah, and IE6 has the exact same support. PNG, no alpha transparency. The single most-used browser in the world is the only one lacking the most attractive feature of PNG files.

Now, it is possible to use JavaScript -the scourge of the Net normally, but this is one of those points where it can be genuinely useful- to make IE apply the AlphaImageLoader filter to PNG images, but no one's managed to make a complete drop-in replacement that will apply to all PNG images im a page yet. It can be done, but it hasn't been done yet.

http://www.mongus.net/pngInfo/

BTW, alpha transparency is only available in the indexed (up to 8 bit) and 32 bit flavors of PNG.