How to apply a raster function to an image service (ArcObjects .NET 10.4 SDK)

Summary

When a client sends a raster function with a GetImage or ExportImage request to the server, the server returns an image with the raster function applied. This topic shows how to apply a raster function to an image service.

Applying a raster function to an image service

To apply a raster function to an image service and export the image, follow these steps:

Define the raster function.
Attach the function to a rendering rule.
Define the image service.
Define the return image type.
Export the image.

The following code example shows how to apply a hillshade function to an elevation service and export the image rendered by the hillshade function:

[C#]

public static string ApplyHillshadeFunction(IImageServer imageServer)
{
    //Define a hillshade function.
    IRasterFunction hillshadeFunction=new HillshadeFunctionClass();
    IRasterFunctionArguments functionArgument=new HillshadeFunctionArgumentsClass()
        ;
    functionArgument.PutValue("Altitude", 45);
    functionArgument.PutValue("Azimuth", 315);
    functionArgument.PutValue("ZFactor", 1.0);

    //Attach the function to a rendering rule.
    IRenderingRule renderRule=new RenderingRuleClass();
    renderRule.Function=hillshadeFunction;
    renderRule.Arguments=functionArgument;
    renderRule.VariableName="DEM";

    //Define the image description.
    IGeoImageDescription geoImageDesc=new GeoImageDescriptionClass();
    geoImageDesc.Compression="LZ77";
    geoImageDesc.Extent=imageServer.ServiceInfo.Extent;
    geoImageDesc.Width=800;
    geoImageDesc.Height=600;
    geoImageDesc.Interpolation=rstResamplingTypes.RSP_BilinearInterpolation;
    IGeoImageDescription2 geoImageDesc2=(IGeoImageDescription2)geoImageDesc;
    geoImageDesc2.RenderingRule=renderRule;

    //Define the return image type.
    IImageType imgType=new ImageTypeClass();
    imgType.Format=esriImageFormat.esriImagePNG;
    imgType.ReturnType=esriImageReturnType.esriImageReturnURL;

    //Export the image.
    IImageResult imgResult=imageServer.ExportImage(geoImageDesc2, imgType);
    return imgResult.URL;
}

[VB.NET]

Public Shared Function ApplyHillshadeFunction(ByVal imageServer As IImageServer) As String
'Define a hillshade function.
Dim hillshadeFunction As IRasterFunction=New HillshadeFunctionClass()
Dim functionArgument As IRasterFunctionArguments=New HillshadeFunctionArgumentsClass()
functionArgument.PutValue("Altitude", 45)
functionArgument.PutValue("Azimuth", 315)
functionArgument.PutValue("ZFactor", 1)

'Attach the function to a rendering rule.
Dim renderRule As IRenderingRule=New RenderingRuleClass()
renderRule.[Function]=hillshadeFunction
renderRule.Arguments=functionArgument
renderRule.VariableName="DEM"

'Define the image description.
Dim geoImageDesc As IGeoImageDescription=New GeoImageDescriptionClass()
geoImageDesc.Compression="LZ77"
geoImageDesc.Extent=imageServer.ServiceInfo.Extent
geoImageDesc.Width=800
geoImageDesc.Height=600
geoImageDesc.Interpolation=rstResamplingTypes.RSP_BilinearInterpolation
Dim geoImageDesc2 As IGeoImageDescription2=DirectCast(geoImageDesc, IGeoImageDescription2)
geoImageDesc2.RenderingRule=renderRule

'Define the return image type.
Dim imgType As IImageType=New ImageTypeClass()
imgType.Format=esriImageFormat.esriImagePNG
imgType.ReturnType=esriImageReturnType.esriImageReturnURL

'Export the image.
Dim imgResult As IImageResult=imageServer.ExportImage(geoImageDesc2, imgType)
Return imgResult.URL
End Function

To use the code in this topic, reference the following assemblies in your Visual Studio project. In the code files, you will need using (C#) or Imports (VB .NET) directives for the corresponding namespaces (given in parenthesis below if different from the assembly name):

Development licensing	Deployment licensing
ArcGIS for Desktop Advanced	ArcGIS for Desktop Advanced
ArcGIS for Desktop Standard	ArcGIS for Desktop Standard
ArcGIS for Desktop Basic	ArcGIS for Desktop Basic
Engine Developer Kit	Engine