HDF5 driver fails to read ODIM georeferencing method

[sjurk]

Using Windows 7 and precompiled libraries downloaded from ​http://www.gisinternals.com/sdk/, GDALINFO in GDAL 1.7.3 reports some ellipsoid/datum info, whereas GDALINFO in GDAL 1.9.2 does not. Does 1.7.3 find the ellipsoid/datum info in the file, or is WGS84/WGS84 assumed by default in 1.7.3, and not in 1.9.2?

The file is a HDF5 ODIM file containing weather radar data, exported from the Norwegian met office (www.met.no). ODIM is the Opera Data and Information Model (​http://www.eumetnet.eu/opera).

The GDALINFO output also differs in that 1.9.2 precedes some of the ODIM metadata tags with dataset1_, and reports the Conventions=ODIM_H5/V2_1 tag. 1.7.3 does not.

Neither version finds the projection info. The string: where:projdef=+proj=utm +zone=32 +ellps=WGS84 +datum=WGS84

or

where:projdef=+proj=aeqd +lat_0=63.536783 +lon_0=10.204000 +R=6371000 +datum=WGS84

appears in two different versions of the file (both enclosed).

Is it possible to look for strings starting with proj= in all metadata items, and extract the info if meaningful?

[sjurk]

Radar file in Azimuthal Equidistant projection

[sjurk]

Radar file in UTM zone 32 projection

[Even Rouault]

trunk r25972 "HDF5: add support for ODIM H5 georeferencing method (#5032)"

There was never a regression. The WGS84 SRS reported in GDAL 1.7.3 was wrong, and later versions just remove that wrong information. The above commit should implement a proper decoding of the georeferencing info, although some tests should be done to check it is OK. See comment in the code for the uncertainty in the decoding.