Trying to summarize what as been said so far, correct me if I'm wrong:
- Everybody here seems to like / want EXIF support in Open EXR.
- Four methods:
[1] Extending the current specification camelCase attributes with new attributes: Looks like to be an easy way for implementation. This is assuming we have a well defined set of attributes / tags. Problem may be that it can take time to construct a list that makes everybody happy.
[2] Like above but the OIIO way which is creating custom prefixed attributes derived from the official exif naming convention ( "Exif:Foo" or "IPTC:Foo" ): Should be relatively easy to implement also.
[3] Supporting XMP: Doesn't looks like complicated either, have a growing worldwide support but will most likely rely on dependencies in order to serialize / parse the data whereas filling existing attributes would be very easy using exrstdattr for example. Adobe is behind the format and provides a very complete SDK, the format itself is an ISO standard which makes it kind of future proof.
http://en.wikipedia.org/wiki/Extensible_Metadata_Platform[4] Extending current specification using either method 1 or 2 and supporting XMP. Best of both world although subject to discrepancies between the attributes and XMP data.
- Adding support for ICC profile attribute.
Larry's way in OIIO is quite cool actually and very similar to what we are doing at MPC actually.
I'm not a huge fan of the current specification set of camelCase attributes because they don't take their name in any other existing specification ( Again correct me if I'm wrong ).
XMP way is although very good but serializing the data while being sure you have propagated the needed EXIF data requires a bit of massaging.