[ptx] Enblend performance with varying exposure values

[JD Smith]

On Tue, 2004-04-27 at 12:10, alexandre jenny wrote:
> I've already planned to create a HDR enblend, that is a rendering
> system which will use many pictures with different exposures to create
> a panorama directly in HDR format by using shutter speed and exposure value.
> It should not be really complex to create by following what Paul debevec did
> for it hdrshop.

Interesting.  I was thinking of avoiding the trouble of multi-exposures
(which really compound the problem of moving scene elements), and just
leverage the 12-bit RAW data many cameras produce directly, along with
an exposure value which changes around the scene to accommodate higher
contrast.  Actually displaying all this contrasty data in an
8bit-per-channel image is a different story, but various tricks can be
used to map high contrast onto those 0...255 values: logarithmic or
asinh scaling for one.  Working with floating-point images in the
processing is a good idea: will hugin handle floating point images well
(I know all the VIGRA stuff is setup for it).

JD