[GRASS-dev] Possible bug in r.out.gdal?

Markus Metz markus.metz.giswork at googlemail.com
Wed Aug 12 04:02:29 EDT 2009


Soeren Gebbert wrote:
> Hello Markus,
> many thanks for your response.
> I guess the behavior of r.out.gdal in case of a raster map in UTM 
> projection and DTED export seems to be correct.
To be precise, it's the behaviour of the gdal library. r.out.gdal leaves 
the format-specific tests to the gdal library, and it was the gdal 
library, not r.out.gdal, that issued the ERROR 5: messages. There is 
nothing that can be done in r.out.gdal to avoid this kind of error.

Markus M

> So i removed the DTED test from the GRASS testsuite, based on your 
> suggestions and the gdal documentation.
>
> soeren
>
> 2009/8/11 Markus Metz <markus.metz.giswork at googlemail.com 
> <mailto:markus.metz.giswork at googlemail.com>>
>
>     From the DTED specs:
>
>     A data file of DTED Level 0, DTED Level 1 or
>     DTED Level 2 is a 1° by 1° cell defined by whole degree latitude and
>     longitude
>     lines on WGS. A DTED file shall not cross whole degree latitude or
>     longitude
>     lines.
>
>     Matrix intervals for DTED Level 0.
>     ZONE LATITUDE latitude x longitude INTERVAL
>     I 0° - 50° North-South 30 x 30 seconds
>     II 50° - 70° North-South 30 x 60 seconds
>     III 70° - 75° North-South 30 x 90 seconds
>     IV 75° - 80° North-South 30 x 120 seconds
>     V 80° - 90° North-South 30 x 180 seconds
>
>     Matrix intervals for DTED Level 1.
>     ZONE LATITUDE latitude x longitude INTERVAL
>     I 0° - 50° North-South 3 x 3 seconds
>     II 50° - 70° North-South 3 x 6 seconds
>     III 70° - 75° North-South 3 x 9 seconds
>     IV 75° - 80° North-South 3 x 12 seconds
>     V 80° - 90° North-South 3 x 18 seconds
>
>     Matrix intervals for DTED Level 2.
>     ZONE LATITUDE latitude x longitude INTERVAL
>     I 0° - 50° North-South 1 x 1 seconds
>     II 50° - 70° North-South 1 x 2 seconds
>     III 70° - 75° North-South 1 x 3 seconds
>     IV 75° - 80° North-South 1 x 4 seconds
>     V 80° - 90° North-South 1 x 6 seconds
>
>     No idea how strict the gdal driver for DTED is, but it seems that
>     it is
>     very strict and won't work without reprojection, followed by setting
>     region extends and resolution according to the desired DTED level.
>
>     Markus M
>
>
>     Soeren Gebbert wrote:
>
>         Dear Devs,
>         i found a strange behavior in r.out.gdal while updating the
>         GRASS test suite.
>
>         Im using the grass6.4svn snapshot:
>         grass-6.4.svn_src_snapshot_2009_08_01.tar.gz.
>         on openSuse 10.3 Linux 2.6.22.19-0.2-bigsmp
>         gdal version 1.6.1
>
>         The test i am implementing tries to export a DCELL raster map
>         (named elevation ) to a DTED file with r.out.gdal.
>         r.out.gdal reports plenty of errors (all of the same type) an
>         exits with return code 0.
>         A dted file is created, but im not sure if it is valid.
>         Exporting the same file with r.out.gdal in ENVI and ELAS
>         formats seems to work correctly.
>
>         These steps are performed:
>
>         GRASS 6.4.0svn > g.region -p
>         projection: 1 (UTM)
>         zone:       32
>         datum:      wgs84
>         ellipsoid:  wgs84
>         north:      5582000
>         south:      5580000
>         west:       400000
>         east:       402000
>         nsres:      20
>         ewres:      20
>         rows:       100
>         cols:       100
>         cells:      10000
>
>         GRASS 6.4.0svn > r.info <http://r.info> <http://r.info> elevation
>
>          +----------------------------------------------------------------------------+
>          | Layer:    elevation                      Date: Sun Apr 30
>         12:48:58 2006    |
>          | Mapset:   PERMANENT                      Login of Creator:
>         soeren          |
>          | Location: TestLocation                                    
>                         |
>          | DataBase: /1/gebbert/src/GRASS_Testsuite                  
>                         |
>          | Title:     ( elevation )                                  
>                         |
>          | Timestamp: none                                            
>                        |
>          |----------------------------------------------------------------------------|
>          |                                                            
>                        |
>          |   Type of Map:  raster               Number of Categories:
>         255             |
>          |   Data Type:    DCELL                                      
>                        |
>          |   Rows:         100                                        
>                        |
>          |   Columns:      100                                        
>                        |
>          |   Total Cells:  10000                                      
>                        |
>          |        Projection: UTM (zone 32)                          
>                         |
>          |            N:    5582000    S:    5580000   Res:    20    
>                         |
>          |            E:     402000    W:     400000   Res:    20    
>                         |
>          |   Range of data:    min = 68.246322  max = 363.529491      
>                        |
>          |                                                            
>                        |
>          |   Data Description:                                        
>                        |
>          |    generated by r.mapcalc                                  
>                        |
>          |                                                            
>                        |
>          |   Comments:                                                
>                        |
>          |    sin(col() * 5) * col() + cos(row() * 5) * row() + 200  
>                         |
>          |                                                            
>                        |
>          +----------------------------------------------------------------------------+
>
>
>         GRASS 6.4.0svn > r.out.gdal --verbose format=DTED type=Float32
>         input=elevation output=/tmp/test.dted ....
>         ERROR 5: Access window out of range in RasterIO().  Requested
>         (0,994) of size 201x1 on raster of 100x100.
>         ERROR 5: Access window out of range in RasterIO().  Requested
>         (0,995) of size 201x1 on raster of 100x100.
>         ERROR 5: Access window out of range in RasterIO().  Requested
>         (0,996) of size 201x1 on raster of 100x100.
>         More than 1000 errors or warnings have been reported. No more
>         will be reported from now.
>         r.out.gdal complete.
>
>
>         GRASS 6.4.0svn > gdalinfo -nomd -noct -stats /tmp/test.dted
>         Driver: DTED/DTED Elevation Raster
>         Files: /tmp/test.dted
>               /tmp/test.dted.aux.xml
>         Size is 201, 1201
>         Coordinate System is:
>         GEOGCS["WGS 84",
>            DATUM["WGS_1984",
>                SPHEROID["WGS 84",6378137,298.257223563]],
>            PRIMEM["Greenwich",0],
>            UNIT["degree",0.0174532925199433],
>            AUTHORITY["EPSG","4326"]]
>         Origin = (399.997500000000002,559.000416666666638)
>         Pixel Size = (0.005000000000000,-0.000833333333333)
>         Corner Coordinates:
>         Upper Left  (     399.998,     559.000) (399d59'51.00"E,559d
>         0'1.50"N)
>         Lower Left  (     399.998,     558.000)
>         (399d59'51.00"E,557d59'58.50"N)
>         Upper Right (     401.002,     559.000) (401d 0'9.00"E,559d
>         0'1.50"N)
>         Lower Right (     401.002,     558.000) (401d
>         0'9.00"E,557d59'58.50"N)
>         Center      (     400.500,     558.500)
>         (400d30'0.00"E,558d30'0.00"N)
>         Band 1 Block=1x1201 Type=Int16, ColorInterp=Palette
>          Min=0.000 Max=0.000
>          Minimum=0.000, Maximum=0.000, Mean=0.000, StdDev=0.000
>          NoData Value=-32767
>          Unit Type: m
>          Color Table (RGB with 365 entries)
>
>
>         Any suggestions what i did wrong?
>         Maybe the region settings are incompatible with the dted
>         output coordinate system?
>         Or is this a correct behavior of r.out.gdal?
>
>         Thanks in advance
>         best regards
>         Soeren
>
>
>
>         ------------------------------------------------------------------------
>
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>
>


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