public sealed class RasterLayer : BasicRasterLayer, ArcGIS.Desktop.Core.IMetadataInfo, IMetadataSource, System.ComponentModel.INotifyPropertyChanged  

{
    string urlRatser = @"C:\Images\Italy.tif";
    await QueuedTask.Run(() =>
    {
        // Create a raster layer using a path to an image.
        // Note: You can create a raster layer from a url, project item, or data connection.
        //Note: needs to be called on the MCT
        var rasterLayerToCreate = LayerFactory.Instance.CreateLayer(new Uri(urlRatser), map) as RasterLayer;
    });
}

{
    // Create a new stretch colorizer definition using default constructor.
    StretchColorizerDefinition stretchColorizerDef = new StretchColorizerDefinition();
    // Create a raster layer creation parameters object with the raster file path.
    var rasterLayerCreationParams = new RasterLayerCreationParams(new Uri("rasterPath"))
    {
        ColorizerDefinition = stretchColorizerDef,
        Name = "rasterLayerName",
        MapMemberIndex = 0
    };

    // Create a raster layer using the colorizer definition created above.
    // Note: You can create a raster layer from a url, project item, or data connection.
    //Note: Run within a QueuedTask
    RasterLayer rasterLayerfromURL =
  LayerFactory.Instance.CreateLayer<RasterLayer>(rasterLayerCreationParams, map);

}

{
  var raster = MapView.Active.Map.GetLayersAsFlattenedList().OfType<RasterLayer>().FirstOrDefault();
  if (raster != null)
  {
    await QueuedTask.Run(() =>
    {
      var rasterTbl = raster.GetRaster().GetAttributeTable();
      var cursor = rasterTbl.Search();
      while (cursor.MoveNext())
      {
        var row = cursor.Current;
      }
    });
  }
}