[QGIS-trac] Re: [Quantum GIS] #3649: Raster calculator does not assign projection correctly to output raster

[Quantum GIS]

#3649: Raster calculator does not assign projection correctly to output raster
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   Reporter:  timlinux                                   |              Owner:  mhugent      
       Type:  bug                                        |             Status:  new          
   Priority:  critical: causes crash or data corruption  |          Milestone:  Version 1.7.0
  Component:  Rasters                                    |            Version:  1.6.0        
   Keywords:                                             |   Platform_version:               
   Platform:  Debian                                     |           Must_fix:  No           
Status_info:  0                                          |  
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Comment(by mhugent):

 r15581 implements a solution where the crs is copied from the first layer
 involved in the calculation.
 It however has two disadvantages:
 - If there is a constant expression (e.g. '42'), the result has no CRS
 assigned. A solution could be to have a crs button in the dialog (but it
 is string freeze now).
 - The CRS is passed to GDAL as WKT, and there can be some loss of
 information depending on the format. E.g. for GeoTiff, the doc says 'Note
 that the GeoTIFF format does not support parametric description of datums,
 so TOWGS84 parameters in coordinate systems are lost in GeoTIFF format'.

 Let me know if there is a better approach to deal with this.

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Ticket URL: <http://trac.osgeo.org/qgis/ticket/3649#comment:1>
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