private void InsertFormXObj(PdfContentByte canvas, PdfDictionary pageDict, PdfStream formXObj, IList <Rectangle> clippingRects, Rectangle annotRect)
{
PdfName xobjName = GenerateNameForXObj(pageDict);
canvas.SaveState();
foreach (Rectangle rect in clippingRects)
{
canvas.Rectangle(rect.Left, rect.Bottom, rect.Width, rect.Height);
}
canvas.Clip();
canvas.NewPath();
canvas.AddFormXObj(formXObj, xobjName, 1, 0, 0, 1, annotRect.Left, annotRect.Bottom);
canvas.RestoreState();
}