OpenImageIO/oiio — pull request #269 by lgritz (2012-03-28 07:36:13+00:00)
Title: Review: ImageCache attribute "deduplicate" 

Add ImageCache attribute "deduplicate" that controls whether the identical-image-deduplication is enabled. (It is enabled by default.)

Disable it for idiff, to be extra super sure we are diffing the actual pixels even if there is a SHA-1 botch.
Also, in maketx, store the SHA-1 in metadata "oiio:SHA-1" and the constant color info in "oiio:ConstantColor", in addition to stashing it in the ImageDescription.