Jachym Cepicky wrote:
HiI would like to write "custom" version of the gdalwarp tool in Python using gdal.ReprojectImage() function, but the only result I get, is just a empty "black" image. The code would look like this: # ------- python code start ------- from osgeo import gdal # let's have georeferenced geotiff inds = gdal.Open("filename.tif") # it *is* georeferenced inds.GetProjection() # '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"]]' # create the driver driver = gdal.GetDriverByName("GTiff") # create new output file outds = driver.Create("outfile.tif",inds.RasterXSize, inds.RasterYSize) # do the transformation - actually no transformation at all gdal.ReprojectImage(inds, outds, inds.GetProjection(), inds.GetProjection())
....
That was all :-( Projection and coordinates can be set using dsout.SetProjection and dsout.SetGeoTransform - that would not be a problem. The problem are the data, which were not copied. I'm I missing something? Could this be a problem of my GDAL installation?
Jachym, The problem is that your output file does not have a geotransform set, so ReprojectImage() does not realize the output file overlaps the area available from the input file. You need to set the geotransform before calling ReprojectImage(). Setting the coordinate system is not critical since ReprojectImage() allows you to pass in an output coordinate system. Best regards, -- ---------------------------------------+-------------------------------------- I set the clouds in motion - turn up | Frank Warmerdam, [email protected] light and sound - activate the windows | http://pobox.com/~warmerdam and watch the world go round - Rush | Geospatial Programmer for Rent _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
