AWARE [SYSTEMS] Imaging expertise for the Delphi developer
AWare Systems, Imaging expertise for the Delphi developer, Home TIFF and LibTiff Mailing List Archive

LibTiff Mailing List

TIFF and LibTiff Mailing List Archive
November 2003

Previous Thread
Next Thread

Previous by Thread
Next by Thread

Previous by Date
Next by Date

Contact

The TIFF Mailing List Homepage
This list is run by Frank Warmerdam
Archive maintained by AWare Systems



Valid HTML 4.01!



Thread

2003.11.26 14:17 "Bug in LogLuv", by Antonio Scuri
2003.11.26 16:31 "Re: Bug in LogLuv", by Greg Ward
2003.11.26 17:41 "Re: Bug in LogLuv", by Antonio Scuri
2003.11.26 17:54 "Re: Bug in LogLuv", by Greg Ward
2003.11.27 15:10 "Re: Bug in LogLuv", by Andrey Kiselev
2003.11.27 15:23 "Re: Bug in LogLuv", by Kai-uwe Behrmann
2003.11.27 15:48 "Re: Bug in LogLuv", by Antonio Scuri
2003.11.27 16:01 "Re: Bug in LogLuv", by Kai-uwe Behrmann
2003.11.27 19:10 "Re: Bug in LogLuv", by Greg Ward

2003.11.26 16:31 "Re: Bug in LogLuv", by Greg Ward

Hi Scuri,

Thanks very much for spotting this bug!  I must have never tested or 
used this particular routine, because as far as I know, it's never 
manifested a problem.  Surely, it would have had it been applied by 
someone.  The 48-bit LogLuv format is not used by any of my 
applications for communication with the library.  I always use floating 
point XYZ or one of the raw LogLuv encodings.

LogLuv TIFF format is used a number of places, notably by Renderpark 
<http://www.linux.org/apps/AppId_4060.html> and Radiance 
<http://www.radiance-online.org> (via the ra_tiff converter).  It is 
also supported by the newest version of HDRshop 
<http://www.debevec.org/HDRShop/>, a program for building and 
manipulating high dynamic-range images, and on the Mac by Photosphere 
<http://www.anyhere.com>, a program for building and cataloging regular 
and HDR images.

LogLuv still has the upper hand as the most efficient (i.e., most 
compact and fastest i/o) of any HDR format, which is why I use it for 
all my own images.  The fact that it covers the entire visible gamut 
also makes it ideal for holding image data on its way to color 
printers, etc., whose gamut does not usually match the typical RGB 
range.  This is what we used it for (and still use it for) at 
Shutterfly <http://www.shutterfly.com>.

I continue to be hopeful that Adobe will start supporting the LogLuv 
and IEEE floating-point TIFF formats, though having had a number of 
interactions with the appropriate technical group over the past few 
months, my hopes are starting to wane.

-Greg