Comment 4 for bug 35582

from wikipedia (note: grain of salt) http://en.wikipedia.org/wiki/XCF

"The Gimp developers have deliberately not published a specification document for the XCF format, in an attempt to safeguard the possibility of doing minor format changes in future versions. Thus the souce code of the Gimp itself (which is freely available) is the only documentation of the format."

"There are very few programs besides the Gimp that are capable of writing XCF files, but some image viewers and conversion software can read the format with varying degrees of success::