Question

I have a PDF file which I need to insert an image on the 1st page and then resize the original size from A4 to some other size.

I manage to add an image into the PDF but not resizing it with the following code:

        string pdfFile = @"C:\Temp\a.pdf";

        PdfReader reader = new PdfReader(pdfFile);

        PdfStamper stamper = new PdfStamper(reader, new FileStream(@"C:\Temp\out.pdf", FileMode.Create), PdfWriter.VERSION_1_5);

        PdfContentByte writer = stamper.GetOverContent(1);

        stamper.FormFlattening = true;
        stamper.SetFullCompression();

        Image topImage = Image.GetInstance(@"C:\Temp\c.jpg");
        topImage.ScalePercent(19f);
        topImage.SetAbsolutePosition(142, 700);
        writer.AddImage(topImage);

        Document myPDF = writer.PdfDocument;
        myPDF.SetPageSize(PageSize.A3);

        stamper.Close();
        stamper = null;

Is there anything wrong or missing in my code?

Answer 1

Below is how a PDF can be resized:

    private string PdfResize(string tmpPdfFilename, string resultRootName)
    {
        try
        {
            string newPdfFilename = resultRootName + ".pdf";
            PdfReader resizeReader = new PdfReader(tmpPdfFilename);

            Rectangle newRect = new Rectangle(0, 0, Convert.ToSingle(_pdfNewSizeW), Convert.ToSingle(_pdfNewSizeH));
            Document doc = new Document(newRect);
            Document.Compress = true;

            PdfWriter resizeWriter = PdfWriter.GetInstance(doc, new FileStream(newPdfFilename, FileMode.Create));
            doc.Open();

            PdfContentByte cb = resizeWriter.DirectContent;

            for (int pageNumber = 1; pageNumber <= resizeReader.NumberOfPages; pageNumber++)
            {
                PdfImportedPage page = resizeWriter.GetImportedPage(resizeReader, pageNumber);
                cb.AddTemplate(page, newRect.Width / resizeReader.GetPageSize(pageNumber).Width, 0, 0,
                               newRect.Height / resizeReader.GetPageSize(pageNumber).Height, 0, 0);
                doc.NewPage();
            }

            doc.Close();
            doc = null;

            return newPdfFilename;
        }
        catch (Exception exp)
        {
            return String.Empty;
        }
    }