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Web Map Specification


The image service uses a mosaic rule to mosaick multiple rasters on the fly. The mosaic rule parameter is used by many image service operations, for example, export image and identify operations.

Referenced by: Image Service Layer (ArcGISImageServiceLayer), Image Service Vector Layer (ArcGISImageServiceVectorLayer)


Property Details
ascending Indicate whether to use ascending or descending order.
fids A list that defines a subset of rasters used in the mosaic, be aware that the rasters may not be visible at all scales.
itemRenderingRule The rendering rule applies on items before mosaicking.
lockRasterIds Lock a few rasters in the image service. Used together with esriMosaicLockRaster.
mosaicMethod A string value that determines how the selected rasters are ordered.
Must be one of the following values:esriMosaicAttribute, esriMosaicCenter, esriMosaicLockRaster, esriMosaicNadir, esriMosaicNone, esriMosaicNorthwest, esriMosaicSeamline, esriMosaicViewpoint
mosaicOperation Use the mosaic operation to resolve overlap pixel values: from first or last raster, use the min, max or mean of the pixel values, or blend them.
If property is present, must be one of the following values: MT_BLEND, MT_FIRST, MT_LAST, MT_MAX, MT_MEAN, MT_MIN, MT_SUM
multidimensionalDefinition Definition of multidimentional variables.
sortField The field name used together with esriMosaicAttribute method.
sortValue The base sort value used together with esriMosaicAttribute method and sortField parameter.
viewpoint Use a view point along with esriMosaicViewpoint.
where Deprecated. Use layerDefinition.definitionExpression instead.


  "operationalLayers": [
      "id": "Terrain_2295",
      "layerType": "ArcGISImageServiceLayer",
      "url": "",
      "visibility": true,
      "bandIds": [],
      "format": "jpgpng",
      "compressionQuality": 75,
      "opacity": 1,
      "title": "Terrain",
      "itemId": "58a541efc59545e6b7137f961d7de883",
      "renderingRule": {
        "rasterFunction": "Aspect"
      "mosaicRule": {
        "mosaicMethod": "esriMosaicSeamline",
        "mosaicOperation": "MT_FIRST"

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