[gdal-dev] Problem reprojecting Clark 1866 to UTM 34 South

Rainer M Krug r.m.krug at gmail.com
Mon May 19 05:00:51 EDT 2008 

I did some more trying and I found the following:
If I convert it to a geotiff, it works, but to a .asc, it doesn't.
Even converting the geotif to an .asc, it changes from PROJCS["WGS 84
/ UTM zone 34S" to PROJCS["WGS 84 / UTM zone 34N" (output below).

Can somebody confirm that as a bug?

Rainer


> gdalwarp -s_srs '+proj=longlat +ellps=clrk66 +no_defs' -t_srs '+proj=utm +zone=34 +south +ellps=WGS84 +datum=WGS84 +units=m +no_defs' hak_ser2.asc hak_ser2_utm34.tif

> gdalinfo hak_ser2_utm34.tif
Driver: GTiff/GeoTIFF
Files: hak_ser2_utm34.tif
Size is 1028, 880
Coordinate System is:
PROJCS["WGS 84 / UTM zone 34S",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.2572235629972,
                AUTHORITY["EPSG","7030"]],
            AUTHORITY["EPSG","6326"]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433],
        AUTHORITY["EPSG","4326"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",21],
    PARAMETER["scale_factor",0.9996],
    PARAMETER["false_easting",500000],
    PARAMETER["false_northing",10000000],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AUTHORITY["EPSG","32734"]]
Origin = (-17476.813424218373257,7568238.577940721064806)
Pixel Size = (1715.257886354814218,-1715.257886354814218)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  INTERLEAVE=BAND
Corner Coordinates:
Upper Left  (  -17476.813, 7568238.578) ( 15d59'39.65"E, 21d54'50.47"S)
Lower Left  (  -17476.813, 6058811.638) ( 15d17'55.46"E, 35d28'46.08"S)
Upper Right ( 1745808.294, 7568238.578) ( 32d58'4.10"E, 21d33'14.79"S)
Lower Right ( 1745808.294, 6058811.638) ( 34d34'58.31"E, 34d50'42.45"S)
Center      (  864165.740, 6813525.108) ( 24d43'43.18"E, 28d45'15.64"S)
Band 1 Block=1028x1 Type=Float32, ColorInterp=Gray

> gdalwarp hak_ser2_utm34.tif hak_ser2_utm34.asc\


> gdalinfo hak_ser2_utm34.asc
Driver: GTiff/GeoTIFF
Files: hak_ser2_utm34.asc
Size is 1028, 880
Coordinate System is:
PROJCS["WGS 84 / UTM zone 34N",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.2572235629972,
                AUTHORITY["EPSG","7030"]],
            AUTHORITY["EPSG","6326"]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433],
        AUTHORITY["EPSG","4326"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",21],
    PARAMETER["scale_factor",0.9996],
    PARAMETER["false_easting",500000],
    PARAMETER["false_northing",0],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AUTHORITY["EPSG","32634"]]
Origin = (-17471.391705359546904,-2431926.174459759611636)
Pixel Size = (1715.270741799227608,-1715.270741799227608)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  INTERLEAVE=BAND
Corner Coordinates:
Upper Left  (  -17471.392,-2431926.174) ( 15d59'39.65"E, 21d54'55.81"S)
Lower Left  (  -17471.392,-3941364.427) ( 15d17'55.27"E, 35d28'51.77"S)
Upper Right ( 1745826.931,-2431926.174) ( 32d58'5.17"E, 21d33'19.99"S)
Lower Right ( 1745826.931,-3941364.427) ( 34d34'59.95"E, 34d50'47.92"S)
Center      (  864177.770,-3186645.301) ( 24d43'43.82"E, 28d45'21.15"S)
Band 1 Block=1028x1 Type=Float32, ColorInterp=Gray


On Mon, May 19, 2008 at 9:56 AM, Rainer M Krug <r.m.krug at gmail.com> wrote:
> On Sat, May 17, 2008 at 10:40 PM, Frank Warmerdam <warmerdam at pobox.com> wrote:
>> Rainer M Krug wrote:
>>>
>>> Hi
>>>
>>> I have a ESRI asc raster in +proj=longlat +ellps=D_Clarke_1866 +no_defs
>>
>> ...
>>>
>>> I want to reproject / warp it into UTM 34 S. I use the following command:
>>>
>>> gdalwarp -s_srs '+proj=longlat +ellps=D_Clarke_1866 +no_defs' -t_srs
>>> EPSG:32734 hak_ser2.asc hak_ser2_utm34.asc
>>>
>>> where EPSG:32734 is the definition for UTM 34 S WGS 84
>>>
>>> But I get:
>>>
>>> rkrug at ecolmod1:~/Documents/Projects/AlienSpread/GIS.local/Rainer_subset>
>>> gdalinfo hak_ser2_utm34.asc
>>> Driver: GTiff/GeoTIFF
>>> Files: hak_ser2_utm34.asc
>>> Size is 1028, 880
>>> Coordinate System is:
>>> PROJCS["WGS 84 / UTM zone 34N",
>>>   GEOGCS["WGS 84",
>>
>> Rainer,
>>
>> I suspect there is a problem with finding some of the support libgeotiff
>> or GDAL coordinate system files.
>>
>> Do you have files in /usr/local/share/epsg_csv?
>>
>> Do you have files in /usr/local/share/gdal?
> A file named gdal_datum.csv in /usr/local/share and
> a grass folder
>
> Are there any specific files I have to look for?
>
> I have the following files with epsg:
>
>> locate epsg
> /opt/grass/etc/epsg_option.tcl
> /usr/lib/R/library/rgdal/gdal/epsg.wkt
> /usr/lib/R/library/rgdal/proj/epsg
> /usr/local/GeoExpressSDK/3rd-party/share/gdal/epsg.wkt
> /usr/local/share/epsg.wkt
> /usr/local/share/proj/epsg
> /usr/share/proj/epsg
>
>
>>
>> I tried a similar command and the South aspect was properly preserved, so
>> I'm getting that when the support files are not found (either by libgeotiff
>> or GDAL) the fallback logic mishandles the south modifier.
>>
>> PS. +ellps=D_Clark_1866 isn't likely to be recognised.  Use +ellps=clrk66.
>>
>> Best regards,
>> --
>> ---------------------------------------+--------------------------------------
>> I set the clouds in motion - turn up   | Frank Warmerdam,
>> warmerdam at pobox.com
>> light and sound - activate the windows | http://pobox.com/~warmerdam
>> and watch the world go round - Rush    | President OSGeo, http://osgeo.org
>>
>>
>
>
>
> --
> Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation
> Biology, UCT), Dipl. Phys. (Germany)
>
> Plant Conservation Unit
> Department of Botany
> University of Cape Town
> Rondebosch 7701
> South Africa
>



-- 
Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation
Biology, UCT), Dipl. Phys. (Germany)

Plant Conservation Unit
Department of Botany
University of Cape Town
Rondebosch 7701
South Africa

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