[postgis-devel] [PostGIS] #297: Implement ST_AsPolygon function for raster

[PostGIS]

#297: Implement ST_AsPolygon function for raster
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 Reporter:  mloskot    |       Owner:  pracine        
     Type:  defect     |      Status:  new            
 Priority:  medium     |   Milestone:  wktraster 0.1.6
Component:  wktraster  |     Version:                 
 Keywords:             |  
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 Function ST_AsPolygon is part of [wiki:WKTRaster/SpecificationWorking01
 Objective 0.1.6e] and shall be implemented:
 {{{
 ST_AsPolygon(raster) -> polygon geometry set
 }}}

 This algorithm is very useful since it ensure that
 ST_AsRaster(ST_AsPolygon(raster)) should returns the same raster as the
 original (because it is based on the centroid of the pixel).

 Open questions:
  * Pierre: Can we directly use the GDAL function by copying the raster
 data into a GDAL structure or should we just copy/adapt the algorythm?

 References:
  *
 [http://trac.osgeo.org/gdal/browser/trunk/gdal/alg/polygonize.cpp?rev=16328
 Raster to Polygon Converter] implemented in GDAL

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/297>
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