Retrieving coverage data

The following shows how to extract coverages.

Retrieving the full coverage

The following request retrieves geosolutions__usa fully, at its native resolution, in its native CRS and format:

Element Description
http://localhost:8083/geoserver/ows The base URL
service=WCS The service
version=2.0.0 The service version
request=GetCoverage The request
coverageId=geosolutions__usa The coverage that should be returned (just one)

Browsers often do not open the file directly, but any image viewer will.

Retrieving the full coverage in a different format

The following request returns the same coverage, but as a PNG (thus, non georeferenced):


The full result as a PNG

The new parameter here is the format one:

Element Description
format=image/png The output format (one of those listed in the capabilities documents)

Getting a subset of the data

Selecting a spatial subset of the data is called trimming in WCS and it’s controlled by subset parameter. Coverages can be N dimensional, so a subset range needs to be specified for each axis (in this case, only Lat and Lon). The following request extracts part of California:

Element Description
subset=Lat(30,42) Latitude range to be extracted
subset=Long(-125,-115) Longitue range to be extracted

A subset of the coverage, as a PNG

Getting a scaled down version of the data

Sometimes one needs the whole area, but the provided resolution is too high for the needs at hand, and the download can be reduced by usin a lower resolution. A simple way to achieve that is to use the scalefactor parameter, which multiplies the output size accordingly:

Element Description
scalefactor=0.5 Scaling factor for the output image

A scaled down version of the coverage, as a PNG

Getting specific bands

With the popularity of multiband sensor imagery from satellites (e.g., Landsat, Sentinel) it can be useful to only download the bands one is interested into. The following request adds a rangesubset parameter to only extract the red band of the layer:

Element Description
rangesubset=RED_BAND Comma separated list of band names to be extracted

A subset of the coverage, as a PNG

Downloading the data in a different projection

Sometimes the downloaded data needs to be integrated with other local data. It can be convenient to have it already in a common Coordinate Reference System. The outputCRS parameter can be used to reproject the coverage, in the following example:

Element Description
outputCRS= The output CRS, in this case, a Lambert designed for Kansas

A subset of the coverage, as a PNG