ImageIdentifyParameters

Property Overview

Property Details

declaredClass Stringreadonly inherited

The name of the class. The declared class name is formatted as esri.folder.className.

geometry Point|Polygon

Input geometry that defines the location to be identified. The location can be a point or a polygon.

maxItemCount Number

Since: ArcGIS API for JavaScript 4.20

Controls the maximum number of returned catalog items, set to 1 to return the top most raster only.

mosaicRule MosaicRuleautocast

Specifies the mosaic rules defining the image sorting order. When a mosaic rule is not specified, center is used.

pixelSize PixelSizeautocast

Specifies the pixel level being identified on the x and y axis. Defaults to the base resolution of the dataset when not specified.

renderingRule RasterFunctionautocast

Specifies the rendering rule for how the requested image should be rendered.

renderingRules RasterFunction

Since: ArcGIS API for JavaScript 4.20

An array the rendering rules to retrieve multiple processed pixel values.

returnCatalogItems Boolean

If true, returns both geometry and attributes of the catalog items. Set to false when catalog items are not needed to significantly improve identify operation's performance.

returnGeometry Boolean

When true, each feature in the catalog items includes the geometry. When false, the features will not display on the map.

Default Value:false

returnPixelValues Boolean

Since: ArcGIS API for JavaScript 4.20

If true, the pixel values of all raster catalog items under the requested geometry. Set to false when catalog item values are not needed to significantly improve identify operation's performance.

timeExtent TimeExtentautocast

Since: ArcGIS API for JavaScript 4.20

A time extent for a temporal data against time-aware imagery layer. For example, it can be used to discover land cover changes by decade.

Method Overview

Method Details

fromJSON(json){*}static

Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. The object passed into the input json parameter often comes from a response to a query operation in the REST API or a toJSON() method from another ArcGIS product. See the Using fromJSON() topic in the Guide for details and examples of when and how to use this function.

Parameter:

json Object A JSON representation of the instance in the ArcGIS format. See the ArcGIS REST API documentation for examples of the structure of various input JSON objects.

Returns:

Type	Description
*	Returns a new instance of this class.

toJSON(){Object}

Converts an instance of this class to its ArcGIS portal JSON representation. See the Using fromJSON() guide topic for more information.

Returns:

Type	Description
Object	The ArcGIS portal JSON representation of an instance of this class.

Type Definitions

PixelSize Object

Specifies the pixel size (or the resolution). The raster at the specified pixel size in the mosaic dataset will be used for the the identify, histogram or statistics calculations on an ImageryLayer.

Properties:

x Number Represents the size of one pixel in map units along the x axis.

y Number Represents the size of one pixel in map units along the y axis.

spatialReference Object optional Spatial reference to be used for the request. The spatial reference of the image service will be used if not specified. Specification: wkid Number optional The wkid of the spatial reference. wkt Number optional The Well known text or wkt of the spatial reference.

See also:

• ImageryLayer.computeHistograms() method
• ImageryLayer.computeStatisticsHistograms() method
• ImageryLayer.identify() method

Example:

// set the pixel size parameter to match the current
// resolution of the view and spatial reference
let pixelSize = {
  x:view.resolution,
  y:view.resolution,
  spatialReference: {
    wkid: view.spatialReference.wkid
  }
}
// set the histogram parameters to request
// data for the current view extent and resolution
let params = new ImageHistogramParameters({
  geometry:  view.extent,
  pixelSize: pixelSize
});

// request for histograms for the specified parameters
layer.computeHistograms(params).then(function(results){
  // results are returned and process it as needed.
  console.log("histograms", results);
})
.catch(function(err){
  console.log("err", err)
});