On Feb 1, 2008 1:24 PM, Martin Desruisseaux <[EMAIL PROTECTED]> wrote: > Simone Giannecchini a écrit : > > Limited ??? I would not say so! :-) > > Limited doesn't need that you can not do sophesticated processing. It just > means > that some operations allowed in "ratio measurements" are not allowed in > "ordinal > measurements", but there still plenty to do with ordinal measurements. > > "Ordinal" and "Ratio" measurements are two extremities of a spectrum (the > theorical cases). There is also a whole range of cases that fall between them. > In RGB we can't said "50 is half the radiance of 100" because the relationship > from sample values to variance may be non-linear (gamma correction, etc.). But > for some usage saying that it is approximatively half is enough for good > result. >
Got it. May I suggest to move this discussion to a wiki page? I can try to prepare one so that we capture ideas there... > Geophysics views in coverage are about ratio measurements. RGB values are not > ratio measurements if by "measurements" we mean a physical quantity like > radiance. Some may said that it is close enough to ratio measurement for their > purpose, but this is user-decision and current coverage module is not well > suited for handling RGB as ratio measurements. It can be improved. > See suggestion above, let's share discussion points and try to close the discussion as fast as possible with a decent agreement. Simone. > > Martin > -- ------------------------------------------------------- Eng. Simone Giannecchini President /CEO GeoSolutions S.A.S. Via Carignoni 51 55041 Camaiore (LU) Italy phone: +39 0584983027 fax: +39 0584983027 mob: +39 333 8128928 http://www.geo-solutions.it ------------------------------------------------------- ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Geotools-devel mailing list Geotools-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-devel
