libgdal-ecw drivers not working in python bindings

[lpinner]

On Ubuntu 12.04 (with the libgdal-ecw plugin built using the gdal-ecw-build script and provided source package and the Intergrapgh/ERDAS ECW/JP2 5.0 and 5.1 SDK), the install looks ok when running gdal utilities, however the following undefined symbol errors are reported when importing gdal in python and the ECW/JP2ECW drivers are not available.

$ gdalinfo --formats|grep -i ecw
  ECW (rw+): ERDAS Compressed Wavelets (SDK 5.0)
  JP2ECW (rw+v): ERDAS JPEG2000 (SDK 5.0)

$ python -c "from osgeo import gdal; print repr((gdal.GetDriverByName('ECW'),gdal.GetDriverByName('JP2ECW')))"
ERROR 1: /usr/lib/gdalplugins/1.10/gdal_ECW_JP2ECW.so: undefined symbol: _ZTI14GDALPamDataset
ERROR 1: /usr/lib/gdalplugins/1.10/gdal_ECW_JP2ECW.so: undefined symbol: _ZTI14GDALPamDataset
(None, None)

If gdal is built completely from source (using --with-ecw=/path/to/ecw/sdk) the ECW/JP2ECW drivers are available and work fine in the python swig bindings.

Note: not directly related to this ticket, but just for info if you are planning to distribute a libgdal-ecw package in Ubuntu 14.04:

Using your libgdal-ecw build scripts on a vanilla gdal 1.11 source tree in Ubuntu 14.04 also works for the gdal utilies, but generates different errors in python.

$ python -c "from osgeo import gdal; print repr((gdal.GetDriverByName('
ECW'),gdal.GetDriverByName('JP2ECW')))"
ERROR 1: /usr/lib/gdalplugins/1.11/gdal_ECW_JP2ECW.so: undefined symbol: GDALRegisterMe
ERROR 1: /usr/lib/gdalplugins/1.11/gdal_ECW_JP2ECW.so: undefined symbol: _ZTI22GDALJP2AbstractDataset
(None, None)

[Bas Couwenberg]

The ECW plugin is not supported.