- updated to 6.6.3-9:
* Eliminate useless message about assuming zero delay when writing
a single-frame MNG, and changed it from Error to Warning when
writing a multiple-frame MNG.
* Only use the first alpha channel in PSD image.
* Only use XPM complying colors for XPM images (e.g. green is rgb(0,255,0)).
* Eliminate bogus "invalid colormap index" when pinging ICO images.
* Support -set density / units.
* Properly map PNG intent to image->rendering_intent
* The orient option sometimes improperly set "undefined" (reference
http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=16795).
* Only list orientation options for the -list orientation option (reference
http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=16801).
* Return proper standard deviation for combined channels (reference
http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=16786).
* Handle transparency properly for the PSD image format.
* Emit a warning if the PNG encoder can't satisfy the color type and
bit depth requested with a "-define" directive.
* The -fx 2e+6/1e+5 argument no longer returns the wrong results (reference
http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=16833).
* Add -subimage-search option to the compare utility.
* Throw exception if image size differs for the compare program but the
-subimage-search option is not specified.