public class CIMRasterStretchColorizer : CIMRasterColorizer, System.ComponentModel.INotifyPropertyChanged, System.Xml.Serialization.IXmlSerializable  

{
    // Check if the Stretch colorizer can be applied to the raster layer.
    //Note: needs to be called on the QueuedTask
    if (rasterLayer.GetApplicableColorizers().Contains(RasterColorizerType.StretchColorizer))
    {
        // Create a new Stretch Colorizer Definition using the default constructor.
        StretchColorizerDefinition stretchColorizerDef_default = new StretchColorizerDefinition();
        // Create a new Stretch colorizer using the colorizer definition created above.
        CIMRasterStretchColorizer newStretchColorizer_default =
        await rasterLayer.CreateColorizerAsync(stretchColorizerDef_default) as CIMRasterStretchColorizer;
        // Set the new colorizer on the raster layer.
        rasterLayer.SetColorizer(newStretchColorizer_default);
    }
}

{
    // Check if the Stretch colorizer can be applied to the raster layer.
    //Get a color ramp from a style
    StyleProjectItem ArcGISColorsStyleItem =
          Project.Current.GetItems<StyleProjectItem>().FirstOrDefault(s => s.Name == "ArcGIS Colors");
    var colorRamps = ArcGISColorsStyleItem.SearchColorRamps("Heat Map 4 - Semitransparent");
    CIMColorRamp colorRampToUse = colorRampList[0].ColorRamp;

    //Note: needs to be called on the QueuedTask
    if (rasterLayer.GetApplicableColorizers().Contains(RasterColorizerType.StretchColorizer))
    {
        // Create a new Stretch Colorizer Definition specifying parameters 
        // for band index, stretch type, gamma and color ramp.
        StretchColorizerDefinition stretchColorizerDef_custom =
    new StretchColorizerDefinition(1, RasterStretchType.ESRI, 2, colorRamp);
        // Create a new stretch colorizer using the colorizer definition created above.
        CIMRasterStretchColorizer newStretchColorizer_custom =
    await rasterLayer.CreateColorizerAsync(stretchColorizerDef_custom) as CIMRasterStretchColorizer;
        // Set the new colorizer on the raster layer.
        rasterLayer.SetColorizer(newStretchColorizer_custom);
    }
}

{
    // Get the image sub-layer from the mosaic layer.
    //Note: needs to be called on the QueuedTask
    ImageMosaicSubLayer mosaicImageSubLayer = mosaicLayer.GetImageLayer();
    // Check if the Stretch colorizer can be applied to the image sub-layer.
    if (mosaicImageSubLayer.GetApplicableColorizers().Contains(RasterColorizerType.StretchColorizer))
    {
        // Create a new Stretch Colorizer Definition using the default constructor.
        StretchColorizerDefinition stretchColorizerDef_default = new StretchColorizerDefinition();
        // Create a new Stretch colorizer using the colorizer definition created above.
        CIMRasterStretchColorizer newStretchColorizer_default =
    await mosaicImageSubLayer.CreateColorizerAsync(stretchColorizerDef_default) as CIMRasterStretchColorizer;
        // Set the new colorizer on the image sub-layer.
        mosaicImageSubLayer.SetColorizer(newStretchColorizer_default);
    }
}

{
    // Get the image sub-layer from the mosaic layer.
    //Note: needs to be called on the QueuedTask
    ImageMosaicSubLayer mosaicImageSubLayer = mosaicLayer.GetImageLayer();
    // Check if the Stretch colorizer can be applied to the image sub-layer.
    if (mosaicImageSubLayer.GetApplicableColorizers().Contains(RasterColorizerType.StretchColorizer))
    {
        // Create a new Stretch colorizer definition specifying parameters
        // for band index, stretch type, gamma and color ramp.
        StretchColorizerDefinition stretchColorizerDef_custom =
    new StretchColorizerDefinition(1, RasterStretchType.ESRI, 2, colorRamp);
        // Create a new stretch colorizer using the colorizer definition created above.
        CIMRasterStretchColorizer newStretchColorizer_custom =
    await mosaicImageSubLayer.CreateColorizerAsync(stretchColorizerDef_custom) as CIMRasterStretchColorizer;
        // Set the new colorizer on the image sub-layer.
        mosaicImageSubLayer.SetColorizer(newStretchColorizer_custom);
    }
}

{
    // Check if the Stretch colorizer can be applied to the image service layer.
    if (imageServiceLayer.GetApplicableColorizers().Contains(RasterColorizerType.StretchColorizer))
    {
        // Create a new Stretch Colorizer Definition using the default constructor.
        StretchColorizerDefinition stretchColorizerDef_default = new StretchColorizerDefinition();
        // Create a new Stretch colorizer using the colorizer definition created above.
        CIMRasterStretchColorizer newStretchColorizer_default =
    await imageServiceLayer.CreateColorizerAsync(stretchColorizerDef_default) as CIMRasterStretchColorizer;
        // Set the new colorizer on the image service layer.
        imageServiceLayer.SetColorizer(newStretchColorizer_default);
    }
}

{
    // Check if the Stretch colorizer can be applied to the image service layer.
    //Note: needs to be called on the QueuedTask
    if (imageServiceLayer.GetApplicableColorizers().Contains(RasterColorizerType.StretchColorizer))
    {
        // Create a new Stretch Colorizer Definition specifying parameters
        // for band index, stretch type, gamma and color ramp. 
        StretchColorizerDefinition stretchColorizerDef_custom =
    new StretchColorizerDefinition(1, RasterStretchType.ESRI, 2, colorRamp);
        // Create a new stretch colorizer using the colorizer definition created above.
        CIMRasterStretchColorizer newStretchColorizer_custom =
    await imageServiceLayer.CreateColorizerAsync(stretchColorizerDef_custom) as CIMRasterStretchColorizer;
        // Set the new colorizer on the image service layer.
        imageServiceLayer.SetColorizer(newStretchColorizer_custom);
    }
}

//If a raster dataset has statistics, you can create a raster layer and get these statistics by accessing the colorizer.
await QueuedTask.Run(() =>
{
  //Accessing the raster layer
  var lyr = MapView.Active.Map.GetLayersAsFlattenedList().OfType<BasicRasterLayer>().FirstOrDefault();
  //Getting the colorizer
  var colorizer = lyr.GetColorizer() as CIMRasterStretchColorizer;
  //Accessing the statistics
  var stats = colorizer.StretchStats;
  var max = stats.max;
  var min = stats.min;
});