Image services

An image service provides a mosaic image view of a large collection of images and a catalog view of the same image collection. An image service can be published from a raster dataset, a raster layer, ISCDef, or a mosaic dataset. Keep in mind that an image service published from a raster dataset or a raster layer is a special case, and it only supports the mosaic image view.

Image services offer the following capabilities:

• Query image service information, including spatial reference, extent, pixel size, pixel type, number of bands, and band statistics.
• Get image pixels for a given image description.
• Get catalog item count and catalog items for a given selection.
• Download the selected original images, or clip the original image and convert to a target format and then download.
• Get image orientation information and read raw pixels in image space from each individual image (catalog item) or native images that compose the catalog item.
• Server side processing based on client specifications through a rendering rule. A raster function or a raster function chain can be specified in the rendering rule and processed by image server. The service creator can also prepare a raster function template (rft.xml) that can be called by clients.
• Identify the image service to get pixel value of the mosaic result, pixel values of participating catalog items in the mosaic view, and a list of participating catalog items as well as their visibilities.
• Image service is time aware. Both GetImage and query requests support Time.
• Measure height, distance and angle, area and perimeter, and centroid.
• Add rasters to an image service, update, and delete catalog items.
• Image service supports raster attribute table, colormap, and histograms.

Images are returned in a byte array and arranged in a band interleaved by pixel format plus a "NoData" mask. The byte array can be optionally compressed using JPEG (plus transparency), and LZ77 compression. Images can also be returned in a well-known format as MIME data, or a URL. The supported well-known image formats include JPEG, PNG, BMP, and TIFF.

Catalog items are returned as a RecordSet whose items contain footprints and other visible fields in the image service catalog, but do not contain actual raster values. The corresponding raster values can be returned through GetImage or ExportImage with a Lock Raster mosaic method ("esriMosaicLockRaster") or through Download method which will download the original images.

A raster, in general, refers to an individual image (raster) in a raster catalog item, a row in a raster catalog. A raster ID (RID) is the object ID of the raster catalog item containing the raster.

WSDL syntax

http://<host name>:<port number>/<arcgis instance>/services/<ServiceName>/ImageServer?wsdl

Methods

Proxy method	Description
Add	Adds rasters to an image service. New catalog items are created using the newly added rasters and optional attribute information.
ComputeHistograms	Compute histograms based on a given extent, mosaic rule, and pixel size.
Delete	Deletes catalog items.
Download	Gets a list of downloadable files of the original images and returns an array of ImageServerDownloadResult value objects for a given set of catalog item IDs and clipping geometry.
Execute	Executes an image service request.
ExportImage	Exports an image in a well-known format (PNG, JPEG, etc) for a given image description.
ExportScaledImage	Exports an image in a supported format (JPEG, PNG, BMP, and TIFF), scales it into a square pixel size, and returns both the image data and the adjusted image extent for a given image description.
GenerateServiceInfo	Generates the new image service info as if a given rendering rule is applied to the target image service.
GetCacheControlInfo	Determines if client side caching is allowed for a cached image service.
GetCacheDescriptionInfo	Gets the cache control info, tile cache info, tile image info, and cache type info for a cached image service.
GetCatalogItemCount	Gets the number of catalog items for a given query filter.
GetCatalogItemIDs	Gets a list of catalog item object IDs of catalog items for a given query filter.
GetCatalogItems	Gets a set of catalog items for a given query filter.
GetFields	Gets the accessible fields of an image service. The accessible fields are defined during publishing and stored in the image service configuration file.
GetFile	Gets the public URL to a given downloadable file.
GetImage	Gets an image in Esri binary format for a given image description.
GetImageTile	Gets the image tile from the cache directory of the image service.
GetKeyProperties	Gets the key properties of image service, such as AcquisitionDate, SensorAzimuth, and so on.
GetMetadata	Gets the metadata of an image service in an Esri style XML string.
GetNativePixelBlock	Gets a pixel block from a given catalog item (RID), a given source image (IID), at a given block/tile location. The block location is defined by the tiling scheme from the raster information.
GetNativeRasterInfo	Gets raster info for all source raster for a given catalog item. Raster info includes tiling scheme, orientation, number of columns and rows, etc., of a raster of a given catalog item.
GetPixelBlock	Gets the pixel block at a given block/tile location from a given catalog item. The block location is defined by the tiling scheme from the raster information.
GetRasterAttributeTable	Gets the raster attribute table, which consists of pixel values, count, and associated attributes (e.g. land use type).
GetRasterInfo	Gets the raster information, including tiling scheme, orientation, number of columns and rows, etc., of a given catalog item.
GetRasterKeyProperties	Gets the key properties of a raster item in an image service, such as AcquisitionDate, SensorAzimuth, and so on.
GetRasterMetadata	Gets the metadata of a raster for a given catalog item in an Esri style XML string.
GetServiceInfo	Gets the information on an image service including extent, spatial reference, minimum pixel size, maximum pixel size, etc.
GetThumbnail	Gets the thumbnail image of the raster for a given catalog item.
GetTileCacheInfo	Gets the tile size, DPI, and other cache configuration properties for a cached image service.
GetTileImageInfo	Gets the image format information for the cached image service.
GetVersion	Gets the image service version number.
GetVirtualCacheDirectory	Gets the virtual directory containing the cache tiles for a given cached image service.
Identify	Identifies the content of an image service for a given location and a given mosaic rule. The location can be a point or a polygon. It returns an ImageServerIdentifyResult containing the pixel value of the mosaic at the specified location/mosaic rule/pixel size, and a set of catalog items that overlap the given geometry, as well as pixel values of each catalog item, and their visibilities.
IdentifyAll	Identifies the content of an image service for a collection of locations and a given mosaic and/or rendering rule. The locations can be points or polygons. It returns an ImageServerIdentifyResult containing the pixel value of the mosaic at a location/mosaic rule/pixel size, and a set of catalog items that overlap the given geometry, as well as pixel values of each catalog item, and their visibilities. Optionally, Geometry or catalog Items may be skipped.
IsFixedScaleImage	Determines if an image service has a cache.
Measure	Measures height, distance and angle, area and perimeter, and centroid.
Update	Updates catalog items (raster or attributes).