Stretch

This sample demonstrates how to apply an ESRI.ArcGIS.Client RenderingRule class on an ArcGISImageServiceLayer to display imagery in different stretch display formats. The stretch display types that are used for the stretch raster function include: None, Standard Deviation, Histogram, and MinMax. To use the sample, define input properties for the stretch raster function via the radio buttons and click Apply to see the changes.

XAML

<UserControl x:Class="ArcGISWPFSDK.StretchImageService"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:esri="http://schemas.esri.com/arcgis/client/2009"
    xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk">

    <Grid x:Name="LayoutRoot" Background="White">
        <Grid.Resources>
            <LinearGradientBrush x:Key="PanelGradient" EndPoint="0.5,1" StartPoint="0.5,0">
                <LinearGradientBrush.RelativeTransform>
                    <TransformGroup>
                        <ScaleTransform CenterY="0.5" CenterX="0.5"/>
                        <SkewTransform CenterY="0.5" CenterX="0.5"/>
                        <RotateTransform Angle="176" CenterY="0.5" CenterX="0.5"/>
                        <TranslateTransform/>
                    </TransformGroup>
                </LinearGradientBrush.RelativeTransform>
                <GradientStop Color="#FF145787" Offset="0.16"/>
                <GradientStop Color="#FF3D7FAC" Offset="0.502"/>
                <GradientStop Color="#FF88C5EF" Offset="0.984"/>
            </LinearGradientBrush>
        </Grid.Resources>
        <esri:Map x:Name="MyMap" MinimumResolution="0.001">
            <esri:Map.Extent>
                <esri:Envelope XMin="-13483041.1159268" YMin="5707158.06847372" XMax="-13300798.7006729" YMax="5776035.73908334">
                    <esri:Envelope.SpatialReference>
                        <esri:SpatialReference WKID="102100"/>
                    </esri:Envelope.SpatialReference>
                </esri:Envelope>
            </esri:Map.Extent>
            <esri:ArcGISImageServiceLayer ID="ImageServiceLayer" 
                                          Url="http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/Portland/CascadeLandsat/ImageServer" 
                                          ImageFormat="PNG8"
                                          NoData="0" InitializationFailed="Layer_InitializationFailed"/>
            <esri:ArcGISTiledMapServiceLayer Opacity="100" 
                    Url="http://services.arcgisonline.com/ArcGIS/rest/services/Reference/World_Transportation/MapServer" />
        </esri:Map>

        <Grid HorizontalAlignment="Right" VerticalAlignment="Top" Margin="0,10,10,0" >
            <Rectangle Fill="{StaticResource PanelGradient}" Stroke="Gray"  RadiusX="10" RadiusY="10" Margin="0,0,0,5">
                <Rectangle.Effect>
                    <DropShadowEffect/>
                </Rectangle.Effect>
            </Rectangle>
            <Rectangle Fill="#FFFFFFFF" Stroke="DarkGray" RadiusX="5" RadiusY="5" Margin="10,10,10,15" />
            <StackPanel Orientation="Vertical" Margin="30,20,20,30" >
                <TextBlock x:Name="ResponseTextBlock" Text="Define input properties for the stretch raster function.  Click Apply to apply the changes." 
                           Width="200" TextAlignment="Left"  TextWrapping="Wrap" Margin="0,0,0,5"  Foreground="Black"/>

                <StackPanel Orientation="Vertical">
                    <RadioButton x:Name="NoneCheckBox" Content="None" GroupName="StretchType" IsChecked="True"  Margin="3,0,0,0"/>
                    <RadioButton x:Name="StandardDevCheckBox" Content="Standard Deviation" GroupName="StretchType"  Margin="3,0,0,0"/>
                    <RadioButton x:Name="HistogramCheckBox" Content="Histogram" GroupName="StretchType" Margin="3,0,0,0" />
                    <RadioButton x:Name="MinMaxCheckBox" Content="MinMax" GroupName="StretchType"  Margin="3,0,0,0"/>
                    <StackPanel Orientation="Horizontal" Margin="3">
                        <TextBlock Text="Standard Deviations" VerticalAlignment="Center" Margin="3"  Foreground="Black" />
                        <TextBox x:Name="StnDevTextBox" Text="2" Width="20"  Foreground="Black"/>
                    </StackPanel>
                    <StackPanel Orientation="Horizontal" Margin="3">
                        <TextBlock Text="Band IDs" Margin="3" VerticalAlignment="Center"  Foreground="Black" />
                        <TextBox x:Name="BandIDsTextBox" Text="3,1,2" Width="50"  Foreground="Black"/>
                    </StackPanel>
                    <TextBlock x:Name="ValidBandIdsTextBlock" Text="3 bands must be defined" Foreground="Red" 
                                       Visibility="Collapsed" />
                </StackPanel>


                <Button Content="Apply" Margin="0,5,5,0" Click="ApplyButton_Click"  />
            </StackPanel>
        </Grid>
    </Grid>
</UserControl>

C#

using System;
using System.Collections.Generic;
using System.Windows;
using System.Windows.Controls;
using ESRI.ArcGIS.Client;

namespace ArcGISWPFSDK
{
    public partial class StretchImageService : UserControl
    {
        public StretchImageService()
        {
            InitializeComponent();
        }

        private void ApplyButton_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                ArcGISImageServiceLayer imageLayer = MyMap.Layers["ImageServiceLayer"] as ArcGISImageServiceLayer;
                RenderingRule renderingRule = new RenderingRule();
                renderingRule.VariableName = "Raster";

                Dictionary<string, object> rasterParams = new Dictionary<string, object>();

                string[] strArray = BandIDsTextBox.Text.Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries);

                if (strArray.Length == 1 || strArray.Length == 2 || strArray.Length > 3)
                {
                    ValidBandIdsTextBlock.Visibility = System.Windows.Visibility.Visible;
                    return;
                }
                else
                    ValidBandIdsTextBlock.Visibility = System.Windows.Visibility.Collapsed;

                renderingRule.RasterFunctionName = "Stretch";
                renderingRule.VariableName = "Raster";

                int stretchType = 0;
                if (StandardDevCheckBox.IsChecked.Value)
                    stretchType = 3;
                else if (HistogramCheckBox.IsChecked.Value)
                    stretchType = 4;
                else if (MinMaxCheckBox.IsChecked.Value)
                    stretchType = 5;

                rasterParams.Add("StretchType", stretchType);
                rasterParams.Add("NumberOfStandardDeviations",
                    string.IsNullOrEmpty(StnDevTextBox.Text) ? 1 : double.Parse(StnDevTextBox.Text));

                double[][] statistics = new double[3][] { 
                    new double[4] { 0.2, 222.46, 99.35, 1.64 }, 
                    new double[4] { 5.56, 100.345, 45.4, 3.96 }, 
                    new double[4] { 0, 352.37, 172.284, 2 } };
                rasterParams.Add("Statistics", statistics);

                double[] gamma = new double[] { 1.25, 2, 3.95 };
                rasterParams.Add("Gamma", gamma);


                int[] numArray = new int[strArray.Length];
                for (int i = 0; i < strArray.Length; i++)
                {
                    numArray[i] = int.Parse(strArray[i]);
                }

                imageLayer.BandIds = numArray.Length < 1 ? null : numArray;


                renderingRule.RasterFunctionArguments = rasterParams;
                imageLayer.RenderingRule = renderingRule;
                imageLayer.Refresh();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void Layer_InitializationFailed(object sender, EventArgs e)
        {
            MessageBox.Show(String.Format("Layer {0} failed to initialize.", (sender as Layer).ID));
        }
    }
}

VB.NET

Imports System.Collections.Generic
Imports System.Windows
Imports System.Windows.Controls
Imports ESRI.ArcGIS.Client

Namespace ArcGISWPFSDK
    Partial Public Class StretchImageService
        Inherits UserControl
        Public Sub New()
            InitializeComponent()
        End Sub

        Private Sub ApplyButton_Click(sender As Object, e As RoutedEventArgs)
            Try
                Dim imageLayer As ArcGISImageServiceLayer = TryCast(MyMap.Layers("ImageServiceLayer"), ArcGISImageServiceLayer)
                Dim renderingRule As New RenderingRule()
                renderingRule.VariableName = "Raster"

                Dim rasterParams As New Dictionary(Of String, Object)()

                Dim strArray As String() = BandIDsTextBox.Text.Split(New Char() {","c}, StringSplitOptions.RemoveEmptyEntries)

                If strArray.Length = 1 OrElse strArray.Length = 2 OrElse strArray.Length > 3 Then
                    ValidBandIdsTextBlock.Visibility = System.Windows.Visibility.Visible
                    Return
                Else
                    ValidBandIdsTextBlock.Visibility = System.Windows.Visibility.Collapsed
                End If

                renderingRule.RasterFunctionName = "Stretch"
                renderingRule.VariableName = "Raster"

                Dim stretchType As Integer = 0
                If StandardDevCheckBox.IsChecked.Value Then
                    stretchType = 3
                ElseIf HistogramCheckBox.IsChecked.Value Then
                    stretchType = 4
                ElseIf MinMaxCheckBox.IsChecked.Value Then
                    stretchType = 5
                End If

                rasterParams.Add("StretchType", stretchType)
                rasterParams.Add("NumberOfStandardDeviations", If(String.IsNullOrEmpty(StnDevTextBox.Text), 1, Double.Parse(StnDevTextBox.Text)))

                Dim statistics As Double()() = New Double(2)() {New Double(3) {0.2, 222.46, 99.35, 1.64}, New Double(3) {5.56, 100.345, 45.4, 3.96}, New Double(3) {0, 352.37, 172.284, 2}}
                rasterParams.Add("Statistics", statistics)

                Dim gamma As Double() = New Double() {1.25, 2, 3.95}
                rasterParams.Add("Gamma", gamma)


                Dim numArray As Integer() = New Integer(strArray.Length - 1) {}
                For i As Integer = 0 To strArray.Length - 1
                    numArray(i) = Integer.Parse(strArray(i))
                Next

                imageLayer.BandIds = If(numArray.Length < 1, Nothing, numArray)


                renderingRule.RasterFunctionArguments = rasterParams
                imageLayer.RenderingRule = renderingRule
                imageLayer.Refresh()
            Catch ex As Exception
                MessageBox.Show(ex.Message)
            End Try
        End Sub

        Private Sub Layer_InitializationFailed(sender As Object, e As EventArgs)
            MessageBox.Show([String].Format("Layer {0} failed to initialize.", TryCast(sender, Layer).ID))
        End Sub
    End Class
End Namespace