[gdal-dev] Contour interpolation tool

[Balint Cristian]

>>> Here is an interesting utility based on GDAL and CImg libraries:
>>> http://www.imagico.de/contour_interpolate/


 Does this colorate a DEM file ?

I wrote recently a similar tool if folks are interested.

  It colorates a DEM after a predefined legend.csv file, 
hower it just colorate over several pre-defined segment
values of legend, linear interpolation or color gradient 
still not works (some code but too early), but i share the 
source code with some examples with pleasure:

http://openrisc.rdsor.ro/segment-dem/segment-dem.tar.bz2

  The good part is that its 100% relyed on gdal, i tryed much
to follow coding style too,  so i didnt use cimg e.g., there are 
some experimental linear color interpolation in HSV space 
instead of RGB but it still require more-tweaking 
(i study now some algorithm for it, how GIMP apply colorize/gradient)
outupt is not good for human eyes still for the interpolation option,
non interpolation works well however (see CLi switches).

 I used it for some generated gdal_grid datas in conjunction with 
gdal's VRT driver stuff, to 'colorize' the  obtained DEM for 
some pollution datas, the produced datas are very nice
and at last satisfy me to not use proprietary vendor tool at all
and be able to done the job with some magic scripting:

http://openrisc.rdsor.ro/segment-dem/out.TIF

  If someone see fantasy we can still work on the interpolation
issue, plus i might suggest insted of statical legend.cvs file
an inteligent internal legend-generator option too wich its
pretty possible at last ArcGIS spatial analyst do it well
with  many options including the mentioned 
auto-legend-classification one. Subject cen be extended
and well thinked, I consider a complete lack of such a good 
free tool for now.


//cristian