Le mercredi 22 janvier 2014 20:27:19, Jason Greenlaw - NOAA Affiliate a écrit : > When attempting to use a polygon shapefile (in custom web mercator > projection) with the gdalwarp cutline operation, operating on a GeoTIFF > (with same projection), the following error is output in both versions > 1.10.0 and 1.10.1: > > ERROR 6: No translation for 'Mercator_Auxiliary_Sphere' to PROJ.4 > format is known.
The issue is that esri-3857.prf contains single quote characters instead of double quotes, and oceans_glakes_50m_3857.prj contain single quotes inside double quotes. Both are not valid AFAIK You should be able to overcome this with : ogr2ogr -a_srs EPSG:3857 oceans_glakes_50m_3857.shp oceans_glakes_50m_3857_fixed.shp and gdalwarp -s_srs EPSG:4326 -t_srs EPSG:3857 -r bilinear -srcnodata 9999.0 -dstnodata 9999.0 -tr 4000 9000 -overwrite -co COMPRESS=LZW -co TILED=yes sst.flt sst_projected.tif > > With GDAL 1.10.0, the operation still completes successfully with a zero > exit status, but with GDAL 1.10.1 the operation fails with a nonzero exit > status, and the resulting GeoTIFF has zeros for all pixels. > > Here is the command I'm using: > > gdalwarp -co COMPRESS=LZW -cutline oceans_glakes_50m_3857.shp > -srcnodata 9999.0 -dstnodata 9999.0 -overwrite sst_global.tif > sst_global_cut.tif > > > The input shapefile was produced by reprojecting with ogr2ogr from > EPSG:4326 to my custom projection (WKT is included below), which is stored > in a *.prf file. The source GeoTIFF is single-band with Float32 pixel > type. > > The custom WKT can be found here: http://jgreenlaw.org/gdal/esri-3857.prf > > The cutline shapefile can be downloaded at: > http://jgreenlaw.org/gdal/oceans_glakes_50m_3857.tar.gz (900kb) > > The source GeoTIFF can be generated from this FLT/HDR raster: > http://jgreenlaw.org/gdal/sst_flt.tar.gz (11mb) by running these commands: > > gdalwarp -s_srs EPSG:4326 -t_srs esri-3857.prf -r bilinear -srcnodata > 9999.0 -dstnodata 9999.0 -tr 4000 9000 -overwrite -co COMPRESS=LZW -co > TILED=yes sst.flt sst_projected.tif > > gdalwarp -co COMPRESS=LZW -te -20037507.0671618 -19971868.8804086 > 20037507.0671618 19971868.8804086 -srcnodata 9999.0 -dstnodata 9999.0 -tr > 4000 9000 sst_projected.tif sst_global.tif > > Does anyone know if this behavior is to be expected when the above error is > output? Is there a better method for reprojecting to Web Mercator that > will align properly in ArcGIS? > > Thanks > -Jason > > > Background: > The reason for using custom WKT for reprojecting to Web Mercator is because > I have experienced alignment problems displaying GDAL-produced GeoTIFFs in > ArcGIS when reprojecting using "EPSG:3857" as the target SRS (this seems to > be related to http://trac.osgeo.org/gdal/ticket/3962). > > I generated the WKT below by copying the 102113 definition in > $GDAL_DATA/esri_extra.wkt and merging information from an ESRI Web Mercator > *.prj file. Using this custom WKT as the target SRS with gdalwarp normally > results in rasters that align properly with ArcGIS Web Mercator data > (without on-the-fly datum transformation). > > > --------------------------------------------------------------------------- > ------------------- Custom WKT for reprojecting to ESRI Web Mercator using > GDAL ( > http://jgreenlaw.org/gdal/esri-3857.prf): > --------------------------------------------------------------------------- > ------------------- > > PROJCS['WGS_1984_Web_Mercator_Auxiliary_Sphere', > GEOGCS['GCS_WGS_1984', > DATUM['D_WGS_1984', > SPHEROID['WGS_1984',6378137.0,298.257223563] > ], > PRIMEM['Greenwich',0.0], > UNIT['Degree',0.0174532925199433] > ], > PROJECTION['Mercator_Auxiliary_Sphere'], > PARAMETER['False_Easting',0.0], > PARAMETER['False_Northing',0.0], > PARAMETER['Central_Meridian',0.0], > PARAMETER['latitude_of_origin',0.0], > PARAMETER['Standard_Parallel_1',0.0], > PARAMETER['Auxiliary_Sphere_Type',0.0], > UNIT['Meter',1.0], > EXTENSION["PROJ4", > "+proj=merc +a=6378137 +b=6356752.314245179 +lat_ts=0.0 +lon_0=0.0 > +x_0=0.0 +y_0=0.0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs" > ], > AUTHORITY["EPSG","3857"] > ] -- Geospatial professional services http://even.rouault.free.fr/services.html _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
