[Openexr-devel] loosing massive amount of information using openexr

[Morten Mikkelsen]

I am trying to use open exr for export/import of height maps.

I am exporting maps which have hundreds of thousands of unique height values.

I have tried exporting to openexr in several different existing applications such as:

xnormal, photoshop, blender and using DevIl (image library).

In all cases I end up with no more than a small handful of unique height values. Roughly 8000.

If on the other hand I export to 16 bit png then I get roughly 65000.

If I export as .raw I of course get all my hundreds of thousands of values.

I have tried all the compression options for openexr. Lossy ones as well as non lossy ones.

None of them are giving me more than roughly 8k unique heights.

I don't know which version of openexr these tools would be using though it clearly wouldn't be the most recent version.

That being said the fact that all 4 are showing me same behavior is leading me to suspect it's a problem with openexr lib or perhaps a former versions of openexr.

Is this a known problem with openexr?

Thanks,

Morten.