Opened 4 months ago

Closed 4 months ago

Last modified 4 months ago

#6759 closed defect (fixed)

gdal_translate from netcdf file shifted (gdal >= 1.10.1)

Reported by: jvh Owned by: warmerdam
Priority: normal Milestone: 2.1.3
Component: default Version: unspecified
Severity: normal Keywords:
Cc:

Description

Using gdal_translate to convert to geotiff a netcdf file containing data on a UTM grid (attached), the output is shifted to the left by 360m.

The enclosed netcdf file (created by gdalwarp itself) contains data on a UTM32 grid (in meters) with a grid spacing of 250m. The top left corner is at Origin = (304250.000000000000000,5094750.000000000000000) . Consistently the netcdf x-coordinates (gridcell centers) start from x = 304375.

Using gdal_translate -of GTIFF DEM_250.nc DEM_250.tif produces a file with the following gdalinfo header:

Driver: GTiff/GeoTIFF
Files: DEM_250.tif
Size is 521, 572
Coordinate System is `'
Origin = (303890.000000000000000,5094750.000000000000000)
Pixel Size = (250.000000000000000,-250.000000000000000)

that is, the result is shifted to the left by exactly 360m. Actually already gdalinfo on the original netcdf file produces the same header.

This happens for all recent gdal versions, starting from 1.10.1 (I also tested 1.11, 2.1.0, 2.1.1, 2.1.2). Tested both on different ubuntu distributions and on MacOSX 10.11 (homebrew).

gdal <= 1.9.2 does *not* have the problem and produces an output file which has correctly

Driver: netCDF/Network Common Data Format
Files: DEM_250.nc
Size is 521, 572
Coordinate System is `'
Origin = (304250.000000000000000,5094750.000000000000000)
Pixel Size = (250.000000000000000,-250.000000000000000)

If repeated gdal_translate are performed (netcdf-->gtiff-->netcdf etc) the output file is shifted to the left by 360m at each iteration.

I tried also with a netcdf file with a different (500m) grid spacing and the resulting shift is still exactly 360m to the left.

Attachments (1)

DEM_250.nc (160.6 KB) - added by jvh 4 months ago.
Example netcdf

Download all attachments as: .zip

Change History (4)

Changed 4 months ago by jvh

Attachment: DEM_250.nc added

Example netcdf

comment:1 Changed 4 months ago by Even Rouault

Resolution: fixed
Status: newclosed

In 37031:

netCDF: fix erroneous detection of a non-longitude X axis as a longitude axis that caused a shift of 360m on the georeferencing (fixes #6759)

comment:2 Changed 4 months ago by Even Rouault

In 37032:

netCDF: fix erroneous detection of a non-longitude X axis as a longitude axis that caused a shift of 360m on the georeferencing (fixes #6759)

comment:3 Changed 4 months ago by Even Rouault

Milestone: 2.1.3

I've pushed a fix. The issue can also be workarounded by specifying "--config GDAL_NETCDF_CENTERLONG_180 NO" to gdalinfo / gdal_translate

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