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The proj4 text for the oblique mercator projection GDBD2009 (EPSG 5247) is missing the parameter +no_uoff in srs.db. The +no_uoff was also missing in earlier versions of GDAL and SpatiaLite but now seems to be fixed in both. I can get correct behaviour for this CRS by creating a custom CRS in the QGIS GUI with +no_uoff added.

This seems to be related to an earlier bug (#1196) - it sounded like that was fixable by regenerating srs.db using crssync (?). Is this something I can / should do myself? I have been building QGIS from source, rather than using the Fedora-distributed RPM.

Here is the proj4 text in QGIS version 2.9.0-Master, code revision aa6db0e

$ echo 'select srid, description, parameters from tbl_srs where srid=5247;' | sqlite3 resources/srs.db 
5247|GDBD2009 / Brunei BRSO|+proj=omerc +lat_0=4 +lonc=115 +alpha=53.31580995 +k=0.99984 +x_0=0 +y_0=0 +gamma=53.13010236111111 +ellps=GRS80 +units=m +no_defs

and here it is in GDAL:

gdalsrsinfo --version
GDAL 2.1.0dev, released 2015/99/99
$ gdalsrsinfo 'EPSG:5247'

PROJ.4 : '+proj=omerc +lat_0=4 +lonc=115 +alpha=53.31580995 +k=0.99984 +x_0=0 +y_0=0 +no_uoff +gamma=53.13010236111111 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs '

and in SpatiaLite 4.2.0:

sqlite> .load mod_spatialite
sqlite> select spatialite_version();
4.2.0
sqlite> select InitSpatialMetaData();
1
sqlite> select srid, ref_sys_name, proj4text from spatial_ref_sys where srid=5247;
5247|GDBD2009 / Brunei BRSO|+proj=omerc +lat_0=4 +lonc=115 +alpha=53.31580995 +k=0.99984 +x_0=0 +y_0=0 +no_uoff +gamma=53.13010236111111 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

cs2cs also works correctly with this CRS in PROJ.4 4.8.0 (PROJ.4 claims that +no_uoff is not used, but it is):

$ echo 114.352966 4.359395 | cs2cs -v +init=epsg:4326 +to +init=epsg:5247
# ---- From Coordinate System ----
#Lat/long (Geodetic alias)
#    
# +init=epsg:4326 +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84
# +towgs84=0,0,0
# ---- To Coordinate System ----
#Oblique Mercator
#    Cyl, Sph&Ell no_rot
#    alpha= [gamma=] [no_off] lonc= or
#     lon_1= lat_1= lon_2= lat_2=
# +init=epsg:5247 +proj=omerc +lat_0=4 +lonc=115 +alpha=53.31580995 +k=0.99984
# +x_0=0 +y_0=0 +gamma=53.13010236111111 +ellps=GRS80 +units=m +no_defs
#--- following specified but NOT used
# +no_uoff
518581.10    482422.80 0.00

Tested on QGIS version 2.9.0-Master, code revision aa6db0e, compiled against GDAL/OGR 2.1.0dev, running against GDAL/OGR 2.1.0dev, compiled against GEOS 3.4.2-CAPI-1.8.2, running against GEOS 3.4.2-CAPI-1.8.2 r3921, PROJ.4 Version 480