[gdal-dev] Using VRT images with derived bands (pixel function) with MapServer

[Yves Jacolin (free)]

Hello,

I used the Makefile file in an archive I found in a GDAL ticket. So I guess I am 
using a .so file.

Y.
Le jeudi 16 février 2012 10:15:58, Armin Burger a écrit :
> Yves
> 
> thanks a lot for the help.
> 
> So it is sufficient to add SetEnv GDAL_DRIVER_PATH ..., place the file with
> the pixel function there, and Mapserver can find pixel function referenced
> in the VRT file? What kind of compilation did you use? Create a shared
> library *.so or is the *.o object file sufficient?
> 
> Armin
> 
> 
> -------- Original-Nachricht --------
> 
> > Datum: Thu, 16 Feb 2012 09:31:11 +0100
> > Von: Yves Jacolin <yjacolin at free.fr>
> > An: gdal-dev at lists.osgeo.org, armin.burger at gmx.net
> > Betreff: Re: [gdal-dev] Using VRT images with derived bands (pixel
> > function) with MapServer
> > 
> > Armin,
> > 
> > I am using such application stack: netcdf > vrt and pixel functions >
> > GDAL
> > 
> > MapServer
> > 
> > We have a tiled layer inside PostGIS and we juste configure the layer
> > like all
> > other tiled datasource:
> > 
> > LAYER
> > 
> >  STATUS ON
> >  NAME "layer_idx"
> >  TYPE POLYGON
> >  CONNECTION "dbname=mydb host=localhost user=myUser password=mypassword"
> >  CONNECTIONTYPE postgis
> >  DATA "the_geom FROM myLayer USING srid=4326"
> >  PROJECTION
> >  
> >   "init=epsg:4326"
> >  
> >  END
> >  METADATA
> >  
> >    "wms_srs"   "EPSG:4326"
> >    "wms_timeextent" "2010-12-20/2010-12-26"
> >    "wms_timeitem" "datetime" #column in postgis table of type timestamp
> >    "wms_timedefault" "2010-12-24T00:00:00Z"
> >    "wms_enable_request" "*"
> >  
> >  END
> > 
> > END
> > 
> > If you want to use the vrt file directly it is also possible as easily
> > as: DATA "vrt/myLayer.vrt"
> > 
> > About register the plugin, in Apache config you have to use SetEnv this
> > 
> > way:
> >    SetEnv GDAL_DRIVER_PATH  directory/mapserver/misc
> >    SetEnv MS_MAPFILE directory/mapserver/mymapfile.map
> >    SetEnv MS_MAPFILE_PATTERN "^directory/mapserver/mymapfile.map"
> > 
> > Hth,
> > 
> > Y.
> > 
> > Le Mercredi 15 Février 2012 19:52:21 Armin Burger a écrit :
> > > Dear all
> > > 
> > > I would be interested in using VRT images with "derived bands" as
> > > described on the VRT image documentation page. This requires the
> > > definition of a pixel function and the registration of this function in
> > > the used application via "GDALAddDerivedBandPixelFunc".
> > > 
> > > The provided sample function is already towards what I'm looking for. I
> > > would just need to adapt it accordingly (calculating band 1 as
> > > combination of source band 1 and 3).
> > > 
> > > Since my main interest is to use such image definition in the context
> > > of Mapserver, my question is if there could be a way to use this also
> > > from Mapserver as application? If yes, where would I need to register
> > > the function and how would I best make the function available to
> > > Mapserver (maybe via an .o file that is created when compiling)? Maybe
> > > somewhere inside mapgdal.c ?
> > > 
> > > Would such a pixel function be used also in case when not the full
> > > resolution image (i.e. TIFF file referenced in the VRT file) is read
> > > but one of the overviews from the .ovr file associated to the Tiff
> > > file?
> > > 
> > > Thanks in advance for any hints
> > > 
> > > Armin
> > > _______________________________________________
> > > gdal-dev mailing list
> > > gdal-dev at lists.osgeo.org
> > > http://lists.osgeo.org/mailman/listinfo/gdal-dev

-- 
Yves Jacolin