http://www.xdepth.com/Copied from their front page ...
XDepth® is an image and video compression solution created to satisfy the increasing demand for augmented precision and color depth in digital imaging.
What's quite unique about XDepth isn't just its superior image quality but its full compatibility with the Jpeg format.
The first software implementation of XDepth supports Adobe® Photoshop® and allows compression of High Dynamic Range pictures.
Might be useful
Richard