PNG Transparency: Mac IE 5.x Screenshots

PNG Transparency

Screenshots from Internet Explorer 5.x for Macintosh

These are half-scale JPEG screen shots of the pngs-img.html and png-IceAlpha.html pages. They were taken by jim@publicbbs.com on Mac OS 9 using Macintosh Internet Explorer 5.0, which was one of the first browsers available with truly excellent PNG support. Click on them to see the full-scale, 24-bit PNG images (481448 and 327918 bytes, respectively).

pngs-img.html

png-IceAlpha.html

As far as Greg can tell, there are no errors in Mac IE 5.0's rendering of PNG transparency. Hats off to Brad Pettit and the rest of the Mac IE team!

This pair of one-third-scale JPEG screen shots shows IE 5.2's handling of gamma and color correction under Mac OS X. They were taken by Tom Barrett on Mac OS X. The full-scale PNG images are 227199 and 178978 bytes, respectively.

png-gammatest.html

png-colortest.html

As can be seen in the top two rows in each section of the gamma page, Mac IE 5.2 handles unlabelled GIFs, unlabelled PNGs, and HTML and CSS colors consistently--which presumably means no gamma correction at all. PNGs with gAMA and sRGB chunks are also handled consistently (i.e., gamma correction is performed), but this handling is not consistent with that of the background colors, which is why the next three rows in each section show interior boundaries. And finally, IE appears not to support the iCCP chunk (ICC color profile) or cHRM chunk at all, though this is not conclusive: the version of the embedded ICC profiles may be newer than what the browser supports, and it's not clear that Apple's ColorSync color management system was installed and/or enabled, which apparently is a requirement for iCCP support to kick in.

Note that IE 5.0 under Mac OS 9 behaves virtually identically; thanks to Ed Robinson for the corresponding screen shots and to Michael Broschat for facilitating things.

Here are some related PNG pages at this site:

Last modified 14 March 2009.