OpenEXR

Industrial Light & Magic(ILM), a division of Lucas Digital
Ltd. LLC, implemented its own extended dynamic range file
format in Summer 2000. The existing 8-bit file format used
at the time could not accurately reproduce images with
extreme contrast between the darkest and brightest regions,
or images with very subtle color gradations.

ILM's extended dynamic range file format has been employed
successfully in the movies Harry Potter, Men in Black II,
and Signs. Several shows currently in production at ILM are
using the new format.

Realizing that various other parties are interested in an
extended dynamic range file format, ILM decided to polish
its new file format a bit, and to publish it. OpenEXR is
the result.