ImageEnView1.AddCaption(CaptionText, ImagePosition, TextAlignment, BackgroundColor, TextColor, Fontname, FontStyle, etc.);

procedure TForm1.AddText1Click(Sender: TObject);
var
  iText: string;
begin
  Screen.Cursor := crHourGlass;
  try
    ImageEnView1.DeSelect;
    ImageEnView1.LayersAdd(ielkText);
    iText := 'Natural Flower';
    TIETextLayer(ImageEnView1.CurrentLayer).Text := iText;
    TIETextLayer(ImageEnView1.CurrentLayer).FillColor := clWebGold;
    TIETextLayer(ImageEnView1.CurrentLayer).Font.Name := 'Arial';
    TIETextLayer(ImageEnView1.CurrentLayer).Font.Size := 10;
    TIETextLayer(ImageEnView1.CurrentLayer).Font.Color := clBlack;
    TIETextLayer(ImageEnView1.CurrentLayer).Font.Style  := [fsBold];
    ImageEnView1.CurrentLayer.PosX := -1;
    ImageEnView1.CurrentLayer.PosY := ImageEnView1.Layers[0].Height;
    ImageEnView1.CurrentLayer.Width := ImageEnView1.Layers[0].Width+1;
    ImageEnView1.CurrentLayer.Height := ImageEnView1.IEBitmap.IECanvas.TextHeight(iText) +  16;
    TIETextLayer(ImageEnView1.CurrentLayer).Alignment := iejCenter;
    TIETextLayer(ImageEnView1.CurrentLayer).Layout := ielCenter;
    ImageEnView1.Update;
    ImageEnView1.LayersMergeAll;
    ImageEnView1.Zoom := 100;
  finally
    Screen.Cursor := crDefault;
  end;
end;