public class CIMPictureGraphic : CIMGraphic, System.ComponentModel.INotifyPropertyChanged, System.Xml.Serialization.IXmlSerializable  

//Create a picture element and also set background and border symbology.

//Construct on the worker thread
await QueuedTask.Run(() =>
{
  //Build 2D envelope geometry
  Coordinate2D pic_ll = new Coordinate2D(6, 1);
  Coordinate2D pic_ur = new Coordinate2D(8, 2);
  //At 2.x - Envelope env = EnvelopeBuilder.CreateEnvelope(pic_ll, pic_ur);
  Envelope env = EnvelopeBuilderEx.CreateEnvelope(pic_ll, pic_ur);

  //Create and add element to layout
  string picPath = @"C:\Temp\WhitePass.jpg";
  //At 2.x - GraphicElement picElm =
  //    LayoutElementFactory.Instance.CreatePictureGraphicElement(
  //                                             layout, env, picPath);
  //         picElm.SetName("New Picture");
  //
  GraphicElement picElm = ElementFactory.Instance.CreatePictureGraphicElement(
                                       layout, env, picPath, "New Picture");

  //(Optionally) Modify the border and shadow 
  CIMGraphic picGra = picElm.GetGraphic();
  CIMPictureGraphic cimPicGra = picGra as CIMPictureGraphic;
  cimPicGra.Frame.BorderSymbol = new CIMSymbolReference();
  cimPicGra.Frame.BorderSymbol.Symbol =
        SymbolFactory.Instance.ConstructLineSymbol(
               ColorFactory.Instance.BlueRGB, 2.0, SimpleLineStyle.Solid);

  cimPicGra.Frame.ShadowSymbol = new CIMSymbolReference();
  cimPicGra.Frame.ShadowSymbol.Symbol =
              SymbolFactory.Instance.ConstructPolygonSymbol(
                    ColorFactory.Instance.BlackRGB, SimpleFillStyle.Solid);

  //Update the element
  picElm.SetGraphic(picGra);
});

// get the current mapview
var mapView = MapView.Active;
if (mapView == null)
  return;

      // Use SourceURL for the URL to the image content. For
      // a local file, use a file path. For a web/internet file
// location, use its URL
      //
      // Supported image types are:
//
// png, jpg, tiff, bmp, gif, svg

      var pictureGraphic = new CIMPictureGraphic
{
  SourceURL = @"C:\Images\MyImage.png",
  Shape = envelope
};

IDisposable _graphic = mapView.AddOverlay(pictureGraphic);