[postgis-devel] [PostGIS] #650: [raster] st_dumpaspolygon create int values

[PostGIS]

#650: [raster] st_dumpaspolygon create int values
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 Reporter:  etiennebr       |       Owner:  jorgearevalo 
     Type:  defect          |      Status:  assigned     
 Priority:  critical        |   Milestone:  PostGIS 2.0.0
Component:  postgis raster  |     Version:  trunk        
 Keywords:                  |  
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Comment(by pracine):

 If you read the doc of the GDALPolygonize function:

 http://www.gdal.org/gdal__alg_8h.html#3f522a9035d3512b5d414fb4752671b1

 it says: "Note that currently the source pixel band values are read into a
 signed 32bit integer buffer (Int32), so floating point or complex bands
 will be implicitly truncated before processing."

 I think this makes it impossible for us to get floats back from this
 function. We could add a parameter saying the number of digits we want and
 multiply every pixel by 10 exp(this number) but this would inply
 multiplying every pixel value: way too long.

 I think the only way will be to have GDAL to work with float values...

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/650#comment:8>
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