How to save and load color maps

Saving and loading color maps

1. Cast the RasterDataset object into a RasterDatasetEdit object.
2. Create a RasterColormap3 object.
3. Load the .clr color map file.
4. Alter the color map through the RasterDatasetEdit object.

1. Cast the RasterDataset object into a RasterBandCollection object.
2. Load a single raster band from the RasterBandCollection into a RasterBand object.
3. Load the RasterBand.Colormap into a RasterColormap3 object.
4. Call the RasterColormap3.SaveTo function to save the .clr file.

[C#]

// Load a color map from a .clr file to a raster dataset.
// .clr string example: "C:\colormap\MyColormap.clr"
public static void LoadColormap(IRasterDataset rasDs, string clrPathAndName)
{
    // Use the IRasterDatasetEdit interface to change the dataset color map.
    IRasterDatasetEdit rasEdit=(IRasterDatasetEdit)rasDs;
    // Create a color map.
    IRasterColormap3 rasColor3=new RasterColormapClass();
    // Load the color map from the .clr file.
    rasColor3.LoadFrom(clrPathAndName);
    // Change the color map of the dataset. 
    rasEdit.AlterColormap((IRasterColormap)rasColor3);
}

// Save a color map from a dataset to a .clr file.
// .clr string example: "C:\colormap\MyNewColormap.clr"
public static void SaveColormap(IRasterDataset rasDs, string clrPathAndName)
{
    // Get the color map band of the dataset.
    IRasterBandCollection rasBC=(IRasterBandCollection)rasDs;
    IRasterBand rasBand=rasBC.Item(0);
    // Query interface (QI) to the IRasterColormap3 interface and save to a .clr file.
    IRasterColormap3 rasColor3=(IRasterColormap3)rasBand.Colormap;
    rasColor3.SaveTo(clrPathAndName);
}

[VB.NET]

' Load a color map from a .clr file to a raster dataset.
' .clr string example: "C:\colormap\MyColormap.clr"

Public Sub LoadColormap(ByVal rasDs As IRasterDataset, ByVal clrPathAndName As String)
    ' Use the IRasterDatasetEdit interface to change the dataset color map.
    Dim rasEdit As IRasterDatasetEdit
    rasEdit=rasDs
    ' Create a color map.
    Dim rasColor3 As IRasterColormap3
    rasColor3=New RasterColormapClass
    ' Load the color map from the .clr file.
    rasColor3.LoadFrom(clrPathAndName)
    ' Change the color map of the dataset.
    rasEdit.AlterColormap(rasColor3)
End Sub

' Save a color map from a dataset to a .clr file.
' .clr string example: "C:\colormap\MyNewColormap.clr"

Public Sub SaveColormap(ByVal rasDs As IRasterDataset, ByVal clrPathAndName As String)
    ' Get the color map band from the dataset.
    Dim rasBC As IRasterBandCollection
    rasBC=rasDs
    Dim rasBand As IRasterBand
    rasBand=rasBC.Item(0)
    ' Query interface (QI) to the IRasterColormap3 interface and save to a .clr file.
    Dim rasColor3 As IRasterColormap3
    rasColor3=rasBand.Colormap
    rasColor3.SaveTo(clrPathAndName)
End Sub

---

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):

• ESRI.ArcGIS.System (ESRI.ArcGIS.esriSystem)
• ESRI.ArcGIS.DataSourcesRaster
• ESRI.ArcGIS.Geodatabase

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