iTextSharp.text.pdf.PdfReader.GetCropBox C# (CSharp) Метод

        public Rectangle GetCropBox(int index) {
            PdfDictionary page = pageRefs.GetPageNRelease(index);
            PdfArray cropBox = (PdfArray)GetPdfObjectRelease(page.Get(PdfName.CROPBOX));
            if (cropBox == null)
                return GetPageSize(page);
            return GetNormalizedRectangle(cropBox);
        }
        

        static void ManipulatePdf()
        {
            using (var ms = new MemoryStream()) {
                var pdf     = "resources/Project.pdf";
                var reader  = new iTextSharp.text.pdf.PdfReader(pdf);
                var stamper = new iTextSharp.text.pdf.PdfStamper(reader, ms);

                var box  = reader.GetCropBox(1);
                var left = box.Left;
                var top  = box.Top;

                // var newRectangle = new iTextSharp.text.Rectangle(left + 20, top - 20, left + 250, top - 40);
                var newRectangle = new iTextSharp.text.Rectangle(left, top, left + 250, top - 40);
                newRectangle.UseVariableBorders = false;

                var pcb = new iTextSharp.text.pdf.PdfContentByte(stamper.Writer);
                pcb.SetColorFill(iTextSharp.text.BaseColor.RED);


                var text = "Hello, world!";

                var annot = iTextSharp.text.pdf.PdfAnnotation.CreateFreeText(stamper.Writer, newRectangle, text, pcb);
                annot.Flags = iTextSharp.text.pdf.PdfAnnotation.FLAGS_PRINT;

                // annot.BorderStyle = new iTextSharp.text.pdf.PdfBorderDictionary(0, 0);
                // annot.Color = GetBaseColor(Color.Yellow);
                // annot.Put(PdfName.DS, new PdfString("font: " + "Tohama" + " " +
                //           (10 * 0.75f) + "pt; text-align: left; color: " +
                //           GetBaseColor(Color.Blue)));
                // annot.Put(PdfName.RC, new PdfString(text.Replace("(?i)<br */?> ", "\n").Replace(" & nbsp; ", " ")));
                // annot.Put(PdfName.ROTATE, new PdfNumber(0));

                stamper.AddAnnotation(annot, 1);
                stamper.Close();

                var output = ms.ToArray();
                System.IO.File.WriteAllBytes(".output/Hello.pdf", output);
            }
        }