Perhaps it should be updated to OptiPNG 0.6.5, as versions 0.6.2 (& below) have unpatched security vulnerabilities:
All past OptiPNG versions, up to and including version 0.6.2, are known to be vulnerable to use-after-free attacks, due to a bug in the GIF image reader. (Many thanks to Roy Tam for the report, and to Bryan McQuade for the fix.)
OptiPNG versions 0.6 and 0.6.1 are known to be vulnerable to array-overflow attacks, due to a bug in the BMP image reader. (Many thanks to an anonymous user for the report.)
0.6.5 was release 2011-01-24.
It looks like support for this plugin is dead. The OptiPNG project itself does provide Win32 builds (no Win64, sadly--would probably be a lot faster). I'm using their pseudo-nightly build (from the Mercurial repo, presumably more recent code than 0.7.1), and it appears to work correctly as a drop-in replacement for the included optipng.exe. 0.7.1 fixes not just security flaws, but an actual image corruption bug for grayscale images.
It would be really nice to see OptiPNG included (stand-alone download if necessary) as an official plugin for PDN, preferably in 64-bit native. libjpeg-turbo wouldn't hurt, either...
OptiPNG file type plugin (November 30, 2008)
in FileType Plugins
Posted
It looks like support for this plugin is dead. The OptiPNG project itself does provide Win32 builds (no Win64, sadly--would probably be a lot faster). I'm using their pseudo-nightly build (from the Mercurial repo, presumably more recent code than 0.7.1), and it appears to work correctly as a drop-in replacement for the included optipng.exe. 0.7.1 fixes not just security flaws, but an actual image corruption bug for grayscale images.
It would be really nice to see OptiPNG included (stand-alone download if necessary) as an official plugin for PDN, preferably in 64-bit native. libjpeg-turbo wouldn't hurt, either...