Splitted PDF size is larger when using the iTextSharp

开发者_如何转开发Dear Team, In my application, i want to split the pdf using itextsharp. If i upload PDF contains 10 pages with file size 10 mb for split, After splitting the combine file size of each pdfs will result into above 20mb file size. If this possible to reduce the file size(each pdf).

Please help me to solve the issue.

Thanks in advance

This may have to do with the resources in the file. If the original document uses an embedded font on each, for example, then there will only be one instance of the font in the original file. When you split it, each file will be required have that font as well. The total overhead will be n pages × sizeof(each font). Elements that will cause this kind of bloat include fonts, images, color profiles, document templates (aka forms), XMP, etc.

And while it doesn't help you in your immediate problem, if you use the PDF tools in Atalasoft dotImage, your task becomes a 1 liner:

PdfDocument.Separate(userpassword, ownerpassword, origPath, destFolder, "Separated Page{0}.pdf", true);

which will take the PDF in orig file and create new pages in the dest folder each named with the pattern. The bool at the end is to overwrite an existing file.

Disclaimer: I work for Atalasoft and wrote the PDF library (also used to work at Adobe on Acrobat versions 1, 2, 3, and 4).

Hi Guys i modified the above code to split a PDF file into multiple Pdf file.

        iTextSharp.text.pdf.PdfReader reader = null;
        int currentPage = 1;
        int pageCount = 0;
        //string filepath_New = filepath + "\\PDFDestination\\";

        System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
        //byte[] arrayofPassword = encoding.GetBytes(ExistingFilePassword);
        reader = new iTextSharp.text.pdf.PdfReader(filepath);
        reader.RemoveUnusedObjects();
        pageCount = reader.NumberOfPages;
        string ext = System.IO.Path.GetExtension(filepath);
        for (int i = 1; i <= pageCount; i++)
        {
            iTextSharp.text.pdf.PdfReader reader1 = new iTextSharp.text.pdf.PdfReader(filepath);
            string outfile = filepath.Replace((System.IO.Path.GetFileName(filepath)), (System.IO.Path.GetFileName(filepath).Replace(".pdf", "") + "_" + i.ToString()) + ext);
            reader1.RemoveUnusedObjects();
            iTextSharp.text.Document doc = new iTextSharp.text.Document(reader.GetPageSizeWithRotation(currentPage));
            iTextSharp.text.pdf.PdfCopy pdfCpy = new iTextSharp.text.pdf.PdfCopy(doc, new System.IO.FileStream(outfile, System.IO.FileMode.Create));
            doc.Open();
            for (int j = 1; j <= 1; j++)
            {
                iTextSharp.text.pdf.PdfImportedPage page = pdfCpy.GetImportedPage(reader1, currentPage);
                pdfCpy.SetFullCompression();
                pdfCpy.AddPage(page);
                currentPage += 1;
            }
            doc.Close();
            pdfCpy.Close();
            reader1.Close();
            reader.Close();

        }

Have you tried setting the compression on the writer?

Document doc = new Document();
    using (MemoryStream ms = new MemoryStream())  
    {
        PdfWriter writer = PdfWriter.GetInstance(doc, ms);
        writer.SetFullCompression();
    }