[postgis-devel] [PostGIS] #1402: [raster] ST_Resample producing incorrect transformation

[PostGIS]

#1402: [raster] ST_Resample producing incorrect transformation
----------------------------+-----------------------------------------------
 Reporter:  dustymugs       |       Owner:  dustymugs    
     Type:  defect          |      Status:  new          
 Priority:  blocker         |   Milestone:  PostGIS 2.0.0
Component:  postgis raster  |     Version:  trunk        
 Keywords:                  |  
----------------------------+-----------------------------------------------
 As per email [http://postgis.refractions.net/pipermail/postgis-
 devel/2011-December/016960.html], ST_Resample is returning raster with
 incorrect coordinates.

 {{{
 WITH
 raster As (
   SELECT  ST_AddBand(ST_MakeEmptyRaster(100, 100, 195000, 450000, 1,
 1, 0, 0, 28992),'32BUI')  As rast
   ),
 sub As (
   SELECT ST_ConvexHull(ST_Resample(rast, 900913)) geom FROM raster
   ),
 sub2 As (
   SELECT ST_Transform(ST_ConvexHull(rast), 900913) geom FROM raster
 )
 SELECT 'st_resample' As class, ST_AsText(geom) FROM sub
 UNION
 SELECT 'st_transform' As class, ST_AsText(geom) From sub2
 UNION
 SELECT 'original' As class, ST_AsText(ST_ConvexHull(rast)) FROM raster
 }}}

 Double checking the upper-left corner coordinates with gdaltrasform proves
 that something is amiss.

 {{{gdaltransform -s_srs EPSG:28992 -t_srs "+proj=merc +a=6378137
 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m
 +nadgrids=@null +no_defs"
 195000 450000
 664595.851266449 6806797.3239794 43.5106153006745
 }}}

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/1402>
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