PNG Transparency: Konqueror 3.0 Screenshots

PNG Transparency

Screenshots from Konqueror 3.0 for Linux

These are half-scale JPEG screenshots of the pngs-img.html, png-IceAlpha.html, png-MagnoliaAlpha.html, png-textures.html, and png-rgba32.html pages. They were taken by Christer Grönblad using Konqueror 3.0 (and KDE 3) under Linux.

Click on the half-scale images to see the full-scale, 24-bit PNG images (265509, 134395 and 260395 bytes, respectively):

pngs-img.html

png-IceAlpha.html

png-MagnoliaAlpha.html

Konqueror's rendering of 32-bit PNG alpha-transparency is pretty good, as can be seen in the rightmost toucan image, but it supports only binary transparency for palette images (which comprise the remainder of this set, aside from the pink, dual-toucan JPEG composite). Even on RGBA images, however, Konqueror occasionally shows some strange banding artifacts. These are visible in the shadow of the rightmost toucan (full-scale image only) and in images 18 and especially 17 of the VRML-textures set (linked full-scale PNG is 238819 bytes):

png-textures.html

The alpha bug may be related to buffer management; note that texture 11 is completely wrong--what's shown is a composite of textures 8 and 11. This may also explain the unusual darkness of the partially transparent areas of textures 11, 12, 17 and 18. Note also the lack of binary transparency in image 15; it should appear as a perfectly circular cutout, as in the thumbnail in the upper right corner.

Konqueror 3.0 does better with 32-bit RGBA PNGs, as noted above. None of the banding artifacts are visible on this page (which is linked to a full-scale, 622462-byte PNG), although the partially transparent regions are still strangely dark:

png-rgba32.html

No word yet on whether Konqueror does gamma correction, but the darkness of the toucans strongly suggests that it does not. (This is probably not related to the alpha-darkness, however.)

Here are some related PNG pages at this site:

Last modified 14 March 2009.