WCS services
The Open Geospatial Consortium, Inc. (OGC), Web Coverage Service (WCS) provides an open specification for sharing raster datasets on the web. ArcGIS for Server allows you to publish WCS services from imagery collections, maps, or geodatabases that contain rasters.
A WCS service returns data in a format that can be used as input for analysis and modeling. This is in contrast with OGC WMS services, which only return a picture of the data. The raster datasets made available through WCS services are referred to as coverages. These should not be confused with the vector datasets available in previous versions of ArcGIS, which were also called coverages.
WCS services are useful if you want to make your raster datasets available online in an open, recognized way across different platforms and clients. Any client built to support the WCS 1.0.0, 1.1.0, 1.1.1, and 1.1.2 specification can view and work with your service.
Client applications work with a WCS service by appending parameters to the service's URL. WCS services published to ArcGIS Server support the following operations:
Request service-level metadata and a brief description of the data (GetCapabilities).
Request a full description of one or more coverages (DescribeCoverage).
Request a coverage in a well-known coverage format (GetCoverage).
You can learn more about WCS services at the Open Geospatial Consortium website. Esri also maintains an Interoperability and Standards web page detailing its support for OGC services in ArcGIS.
Creating a WCS service
In ArcGIS Server, WCS is exposed as a capability of a map service, an image service, or a geodata service. To create a WCS service, you need to create one of these three services and enable the WCS capability. The sources for WCS services should be one of these:
A map containing raster layers or mosaic layers
A raster dataset or a mosaic dataset
A layer file referencing a raster dataset or a mosaic dataset
A geodatabase that contains raster data
Note:Personal geodatabases are not supported at ArcGIS 10.1 for Server.
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To create a WCS service from a map service, open ArcMap and create a map document containing the raster layers you want to serve. When doing so, keep in mind that only the raster data in the map will be served in a WCS service; the layer properties will not be maintained, and any feature data will be excluded from the WCS service. When you're finished with your map document, publish it as a map service with the WCS capability enabled. The service can then be consumed by any client that supports the OGC WCS specification.
To create a WCS service from an image service, prepare the raster dataset, mosaic dataset, or layer file referencing a raster dataset or mosaic dataset that you want to publish, then publish it as an image service with the WCS capability enabled.
To create a WCS service from a geodata service, create a geodatabase (file or ArcSDE), load the raster data you want to serve into the geodatabase, then publish the geodatabase as a geodata service with the WCS capability enabled.
A WCS service created from a map service or a geodata service may contain multiple coverages. However, the source raster data must have a valid spatial reference. A WCS service from an image service contains a single WCS coverage.
Configuring WCS service properties
A WCS service's properties are reflected in its capabilities files so that whoever consumes the service can have a better understanding of the service publisher. When publishing a WCS service with system-generated capabilities files (the default), it is recommended that you populate the WCS service properties. For information about each WCS service property you can set, see Available WCS service properties. Additionally, the following topics include instructions on how to get to the location where you can set WCS service properties:
Setting WCS properties using an external capabilities file
If you want more flexibility over how the service advertises its capabilities, you can use external capabilities files. For example, WCS services hosted on ArcGIS Server only support their native spatial reference system and WGS84. Given that ArcGIS Server supports thousands of predefined spatial reference systems, these can be added to a WCS service and advertised to WCS clients by using external WCS capabilities files. See Using external capabilities files with WCS services for more information.
Securing WCS services
A WCS service exposes an ArcGIS Server map, geodata, or image service to WCS consumers. The security for a WCS service is managed by controlling the security of its parent map, geodata, or image service. If a particular role, for example, Planners, is denied access to a map, then Planners will not be able to access the map regardless of whether they try to consume it through simple object access protocol (SOAP), representational state transfer (REST), or WCS interfaces.
ArcGIS Server supports a number of different authentication schemes. Services that are expected to be accessed via OGC interfaces should be secured using HTTP Basic or HTTP Digest. Most OGC clients (both non-Esri and Esri clients) will understand and work with these widespread standard authentication schemes.
Consuming WCS services
To connect to a WCS service, you need to know the URL. When you use ArcGIS Server to publish a WCS service, its URL takes this format:
http://<server name>:<port number>/services/<folder name (if applicable)>/<service name>/<service type (can be MapServer, ImageServer, or GeoDataServer)>/WCSServer?
Remember that the WCS capability is available for map services, image services, and geodata services. This is why there are three options for the service type.
WCS service URL examples
If you have a folder Japan containing the map service Tokyo, running on myServer with the port number 6080, the URL of your WCS service would look like this:
http://myServer:6080/arcgis/services/Japan/Tokyo/MapServer/WCSServer?
If you have an image service IdahoImages running on myServer with the port number 6080, your URL for the WCS service would look like this:
http://myServer:6080/arcgis/services/IdahoImages/ImageServer/WCSServer?
If you have a folder Ohio containing the geodata service SummitCounty running on myServer with the port number 6080, your URL for the WCS service would look like this:
http://myServer:6080/arcgis/services/Ohio/SummitCounty/GeoDataServer/WCSServer?
For more information on how to consume a WCS service, see Communicating with a WCS service in a web browser.
Supported output formats
Supported output formats for WCS services are GeoTIFF, NITF, HDF, JPEG, JPEG2000, and PNG. To learn more about how these image formats are supported in ArcGIS, see Supported raster dataset file formats in the ArcGIS Help.