[postgis-users] How do you use PostGIS Raster?

[Pierre Racine]

Thanks Mathieu,

Could you provide us with some numbers? How many geometries do you intersect? What is the total area/length covered by those geometries? With what raster size? How long it takes? Which kind of machine are you using? I would really like to use your numbers in my presentation.

Pierre

> -----Original Message-----
> From: Mathieu Basille [mailto:basille at ase-research.org]
> Sent: Wednesday, June 08, 2011 10:09 PM
> To: PostGIS Users Discussion
> Cc: Pierre Racine; Marie-Claude Labbé
> Subject: Re: [postgis-users] How do you use PostGIS Raster?
> 
> Dear Pierre,
> 
> Here, we are using PostGIS to analyze large datasets combining rasters and
> vectors. Basically, we are looking at movement and habitat selection in a
> predator-prey system, using GPS-collar data over large areas. The major use of
> PostGIS Raster is for the intersection of prey steps (line segments or buffers
> around these segments) with different raster:
> Landsat (landcover type), slope, road density, relative probability of occurrence
> of the predator, etc. Note that we first tried to use ArcGIS for this step, without
> success, due to many bugs and the need to correct them by hand (which was
> largely too time-consuming). We also used PostGIS Raster to intersect predator
> locations with the Landsat map to estimate Resource Selection Functions (RSF)
> in order to build maps of relative probability of occurrence. In the end,
> information of the intersections were used in R to characterize movements of
> the preys on the landscape.
> 
> Best,
> Mathieu Basille.
> 
> 
> Le 03/06/2011 08:28, Pierre Racine a écrit :
> > Hi all,
> >
> > I'm preparing a presentation and I need some use cases for PostGIS Raster. I
> would be grateful if people already using the raster side of PostGIS would
> describe what they already do it. Bborie, Jorge, Regina, others? These uses
> cases are vital for the project.
> >
> > On my side we are using PostGIS raster to do raster/vector analysis over large
> datasets. Basically determining mean values for temperature (raster), elevation
> (raster) for fauna observations (point buffers). Converting everything to vector
> and using desktop solutions proved impracticable for datasets covering the
> extent of Canada.
> >
> > For those who did not try the raster extension yet, don't be shy to express your
> planned experiments or your expectations.
> >
> > Thanks all for your contribution to the project,
> >
> > Pierre
> > _______________________________________________
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> > postgis-users at postgis.refractions.net
> > http://postgis.refractions.net/mailman/listinfo/postgis-users
> 
> --
> 
> ~$ whoami
> Mathieu Basille, Post-Doc
> 
> ~$ locate
> Laboratoire d'Écologie Comportementale et de Conservation de la Faune
> + Centre d'Étude de la Forêt
> Département de Biologie
> Université Laval, Québec
> 
> ~$ info
> http://ase-research.org/basille
> 
> ~$ fortune
> ``If you can't win by reason, go for volume.''
> Calvin, by Bill Watterson.