Derive Stream As Line

inputSurfaceRaster

(Required)

The input raster representing a surface.

Syntax: This parameter can be specified as a portal item ID, a URL to a raster image service layer, a cloud raster dataset, or a shared raster dataset.

Examples:

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//Portal item as input raster
"inputSurfaceRaster": {"itemId": <portal item id>}

//URL as input raster
"inputSurfaceRaster": {"url": <image service layer url>}

outputStreamFeaturesName

(Required)

The name of the output feature service that will contain the stream features.

The task will create a feature service of the results. You can define the name of the service.

Output name example:

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"outputStreamFeaturesName":{"serviceProperties":{"name":"testrasteranalysis"}}

Output raster examples:

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//Output portal item:
"outputStreamFeaturesName":{"itemId": <portal item id>}

//Output url:
"outputStreamFeaturesName":{"url": <image service url>}

//Output raster layer service:
"outputStreamFeaturesName":{"service properties":
  {"name":"testrasteranalysis",
  "serviceUrl":"https://<server name>/server/rest/services/Hosted/testrasteranalysis/ImageServer",
  "itemProperties":{"itemId":"8cfbd3ec25584d0d8f4ed23b8ff7c43b","folderId":"sdfwerfbd3ec25584d0d8f4"}}
}

inputDepressionsData

An optional dataset that defines real depressions.

The depressions can be defined through a raster or a feature layer.

If the input is a raster, the depression cells must take a valid value, including zero, and the areas that are not depressions must be NoData.

Raster input example:

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"inputDepressionsData":{"url": <image service layer url>}

Feature input examples:

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//Feature layer URL
"inputDepressionsData":{"url": <feature service layer url>}

//Feature collection
"inputDepressionsData":{"layerDefinition": {}, "featureSet": {}}

inputWeightRaster

An optional input raster dataset that defines the fraction of flow that contributes to flow accumulation at each cell.

The weight is only applied to the accumulation of flow.

If no accumulation weight raster is specified, a default weight of 1 will be applied to each cell.

Example:

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"inputWeightRaster":{"url": <image service layer url>}

accumulationThreshold

The threshold for determining whether a given cell is part of a stream in terms of the total area that flows into such cell.

streamDesignationMethod

Specifies the method that will be used to assign a unique value of stream sections between intersections or an order to the segments of streams in the output.

• CONSTANT —The output cell values will all equal 1. This is the default.

• UNIQUE —Each stream will have a unique ID between intersections in the output.

• STRAHLER —The Strahler method, in which stream order only increases when streams of the same order intersect, will be used. The intersection of a first-order and second-order link will remain a second-order link, rather than creating a third-order link.

• SHREVE —The Shreve method, in which stream order is assigned by magnitude, will be used. All links with no tributaries are assigned a magnitude (order) of 1. Magnitudes are additive downslope. When two links intersect, their magnitudes are added and assigned to the downslope link.

• HACK —The Hack method, in which each stream segment is assigned an order greater than the stream or river to which it discharges, will be used. For example, the main river channel is assigned an order of 1, all stream segments discharging to it are assigned an order of 2, any stream discharging to an order 2 stream is assigned an order of 3, and so on.

simplify

Specifies whether the output stream lines will be smoothed into simpler shapes.

Syntax: A Boolean value as either true or false .

• A value of true specifies that the stream feature lines will be simplified using the Douglas-Peucker algorithm with a tolerance of sqrt(0.5) * cell size. This is the default.
• A value of false specifies that the stream feature lines will not be smoothed.

context

Contains additional settings that affect task processing. This task has the following settings:

• Extent (extent )—A bounding box that defines the analysis area.

• Output Spatial Reference (outSR )—The output raster will be projected into the output spatial reference.

• Snap Raster (snapRaster )—The output raster will have its cells aligned with the specified snap raster.

• Cell Size (cellSize )—The output raster will have the resolution specified by cell size.

• Mask (mask)—Only cells that fall within the analysis mask will be considered in the operation.

f

The response format. The default response format is html .

Values: html | json | pjson