That's correct for DGDecNV and DGDenoise. For DGHDRtoSDR go here:
http://rationalqm.us/hdr/
DGDecNV requires a donation. DGHDRtoSDR is freeware. If you use the latter stand-alone then you will need a source filter that delivers high bit depth. DGSource() is the natural choice (part of DGDecNV).