[gdal-dev] GetProjection returns empty string, python 3.7

[Nicolas Cadieux]

New info!

GetProjection works with gdal python 2.2.2 and 2.3.3 but not with with 
gdal 3.0.2.  Is this a change in the gdal library?

Nicolas

On 2020-10-26 1:53 p.m., Nicolas Cadieux wrote:
> Hi,
>
> In case mail question was not clear, I have posted the questions about 
> this on stackexchange.  I posted a full code that you can run exposing 
> my problem and question.
>
> Thanks
>
> Nicolas
>
> https://gis.stackexchange.com/questions/377567/cannot-get-projection-from-raster-dataset-using-getprojection 
>
>
> On 2020-10-25 9:31 p.m., Nicolas Cadieux wrote:
>> Hi,
>>
>> With the following code, I get an empty string indicating the 
>> projection is not valid.
>>
>> from osgeo import gdal, osr
>> raster_ds = gdal.Open(r"C:\temp\180922_WTE3.tif")
>> target_ds = 
>> driver.Create(r"c:\temp\output.tif",xsize=raster_ds_ncol,ysize=raster_ds_nrow,bands 
>> = 1,eType = gdal.GDT_Float32)
>> (array is a numpty array.)
>> raster_srs = osr.SpatialReference()
>> raster_srs.ImportFromWkt(raster_ds.GetProjectionRef())
>> target_ds.SetProjection(raster_srs.ExportToWkt())
>> target_ds.GetRasterBand(1).WriteArray(array)
>> raster_ds = None #close dataset
>> target_ds=None
>>
>> Below is the result of gdal info from qgis. File appears to have a 
>> valid projection and is properly georeferenced in QGIS using other 
>> data sets.   Is this projection wrong or am I missing something in my 
>> python code?  The goal is to extract the projection from raster_ds 
>> set in order to apply to target_ds.  I can create the file, apply a 
>> geotransform but can't get the projection.  Can you help?
>>
>> Thanks/merci!
>>
>> Nicolas
>>
>> QGIS version: 3.14.16-Pi
>> QGIS code revision: df27394552
>> Qt version: 5.11.2
>> GDAL version: 3.0.4
>> GEOS version: 3.8.1-CAPI-1.13.3
>> PROJ version: Rel. 6.3.2, May 1st, 2020
>> Processing algorithm…
>> Algorithm 'Raster information' starting…
>> Input parameters:
>> { 'EXTRA' : '', 'INPUT' : 'C:/temp/180922_WTE3.tif', 'MIN_MAX' : 
>> False, 'NOGCP' : False, 'NO_METADATA' : False, 'OUTPUT' : 
>> 'TEMPORARY_OUTPUT', 'STATS' : False }
>>
>> GDAL command:
>> gdalinfo C:/temp/180922_WTE3.tif
>> GDAL command output:
>> Warning 1: TIFFReadDirectory:Sum of Photometric type-related color 
>> channels and ExtraSamples doesn't match SamplesPerPixel. Defining 
>> non-color channels as ExtraSamples.
>>
>> Driver: GTiff/GeoTIFF
>> Files: C:/temp/180922_WTE3.tif
>> Size is 1194, 2783
>> Coordinate System is:
>> PROJCRS["WGS 84 / UTM zone 18N",
>> BASEGEOGCRS["WGS 84",
>> DATUM["World Geodetic System 1984",
>> ELLIPSOID["WGS 84",6378137,298.257223563,
>> LENGTHUNIT["metre",1]]],
>> PRIMEM["Greenwich",0,
>> ANGLEUNIT["degree",0.0174532925199433]],
>> ID["EPSG",4326]],
>> CONVERSION["UTM zone 18N",
>> METHOD["Transverse Mercator",
>> ID["EPSG",9807]],
>> PARAMETER["Latitude of natural origin",0,
>> ANGLEUNIT["degree",0.0174532925199433],
>> ID["EPSG",8801]],
>> PARAMETER["Longitude of natural origin",-75,
>> ANGLEUNIT["degree",0.0174532925199433],
>> ID["EPSG",8802]],
>> PARAMETER["Scale factor at natural origin",0.9996,
>> SCALEUNIT["unity",1],
>> ID["EPSG",8805]],
>> PARAMETER["False easting",500000,
>> LENGTHUNIT["metre",1],
>> ID["EPSG",8806]],
>> PARAMETER["False northing",0,
>> LENGTHUNIT["metre",1],
>> ID["EPSG",8807]]],
>> CS[Cartesian,2],
>> AXIS["(E)",east,
>> ORDER[1],
>> LENGTHUNIT["metre",1]],
>> AXIS["(N)",north,
>> ORDER[2],
>> LENGTHUNIT["metre",1]],
>> USAGE[
>> SCOPE["unknown"],
>> AREA["World - N hemisphere - 78°W to 72°W - by country"],
>> BBOX[0,-78,84,-72]],
>> ID["EPSG",32618]]
>> Data axis to CRS axis mapping: 1,2
>> Origin = (459417.200000000011642,5028584.700000000186265)
>> Pixel Size = (0.050000000000000,-0.050000000000000)
>> Metadata:
>> AREA_OR_POINT=Area
>> TIFFTAG_XRESOLUTION=1
>> TIFFTAG_YRESOLUTION=1
>> Image Structure Metadata:
>> INTERLEAVE=BAND
>> Corner Coordinates:
>> Upper Left ( 459417.200, 5028584.700) ( 75d31' 7.03"W, 45d24'34.58"N)
>> Lower Left ( 459417.200, 5028445.550) ( 75d31' 6.99"W, 45d24'30.07"N)
>> Upper Right ( 459476.900, 5028584.700) ( 75d31' 4.28"W, 45d24'34.59"N)
>> Lower Right ( 459476.900, 5028445.550) ( 75d31' 4.24"W, 45d24'30.08"N)
>> Center ( 459447.050, 5028515.125) ( 75d31' 5.63"W, 45d24'32.33"N)
>> Band 1 Block=1194x1 Type=UInt16, ColorInterp=Red
>> ...
>> Band 288 Block=1194x1 Type=UInt16, ColorInterp=Undefined
>>
>>
>>