[postgis-devel] [PostGIS] #493: [wktraster] ST_DumpValues to Dump Pixel values

[PostGIS]

#493: [wktraster] ST_DumpValues to Dump Pixel values
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  Reporter:  robe       |       Owner:  pracine         
      Type:  defect     |      Status:  new             
  Priority:  medium     |   Milestone:  WKTRaster Future
 Component:  wktraster  |     Version:  trunk           
Resolution:             |    Keywords:                  
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Comment (by pracine):

 Isn't the ST_SelectByValue(raster, ‘expression’) fulfilling this need:

 ST_DumpASPolygons(ST_SelectBandByValue(raster,1, 'val >= 15 and val <=
 100'))

 Then you can intersect the resulting geometries with any sampling
 assemblage you desire? Actually you don't have to call ST_DumpASPolygons()
 yourself as doing ST_Intersections() between your grid and the result of
 ST_SelectByValue(raster,'val >= 15 and val <= 100') will do it for you.

 Would that give approximately the same result? I`m just trying to see if
 there is enough tools in the planned function to provide you with what you
 expect.

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/493#comment:4>
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