Overlay one page onto another (stitch PDFs)

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This is a quick and relatively simple way to overlay one page onto another. This is sometimes called stitching, overlaying, watermarking, etc, -- although each of those terms can refer to slightly different tasks as well. 
The benefit of overlaying one page onto another the way I've outlined below is that you don't have to render either of the pages as an image, so in the final output, you'll still be able to select individual elements on the page, including text.
I've used Delphi for this sample, but the syntax is quite straightforward and it shouldn't be difficult to understand.
------------
procedure TForm2.btnOverlayClick(Sender: TObject);
var
  FileA: Integer;
  FileB: Integer;
  CapturedPageID: Integer;
  PageHeight: Double;
  PageWidth: Double;
  Path: AnsiString;
begin
  QP := TQuickPDF0716.Create;
  try
    UnlockResult := QP.UnlockKey('...'); // Insert trial or paid license key here
    if UnlockResult = 1 then
    begin
    // You can only use the DrawCapturedPage function if the captured page is in the same
    // document, so first we'll need to merge the two pages that we wish to overlay together
    // into one document.
    if dlgOpen.Execute then
      begin
         QP.LoadFromFile(dlgOpen.FileName);
         FileA := QP.SelectedDocument();
      end;
      if dlgOpen.Execute then
      begin
         QP.LoadFromFile(dlgOpen.FileName);
         FileB := QP.SelectedDocument();
      end;
      // After merging FileB is automatically deleted, leaving only FileB which is now a combination of FileA and FileB
      QP.SelectDocument(FileA);
      QP.MergeDocument(FileB);

      // Capture the second page in the merged document
      CapturedPageID := QP.CapturePage(2);
      // Now select the first page and retrieve its height and width
      QP.SelectDocument(FileA);
      QP.SelectPage(1);
      PageHeight := QP.PageHeight();
      PageWidth := QP.PageWidth();
      // Draw the captured page onto the currently selected page
      QP.DrawCapturedPage(CapturedPageID, 0, PageHeight, PageWidth, PageHeight);

      // Save the stitched file to disk
    if dlgSave.Execute then
      begin
        Path := dlgSave.FileName;
      end;
      QP.SaveToFile(Path);
    end;
  finally
    QP.Free;
  end;
end;
------------

Obviously if the two pages don't have the same dimensions then you'll need to do some tinkering, but if they do, then this code should work quite well.

Edited by Rowan - 07 Sep 09 at 2:40AM

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Rowan Members Profile Find Members Posts Moderator Group Joined: 10 Jan 09 Status: Offline Points: 398	Post Options Post Reply Quote Rowan Report Post Thanks(0) Quote Reply Topic: Overlay one page onto another (stitch PDFs) Posted: 07 Sep 09 at 2:35AM
	This is a quick and relatively simple way to overlay one page onto another. This is sometimes called stitching, overlaying, watermarking, etc, -- although each of those terms can refer to slightly different tasks as well. The benefit of overlaying one page onto another the way I've outlined below is that you don't have to render either of the pages as an image, so in the final output, you'll still be able to select individual elements on the page, including text. I've used Delphi for this sample, but the syntax is quite straightforward and it shouldn't be difficult to understand. ------------ procedure TForm2.btnOverlayClick(Sender: TObject); var FileA: Integer; FileB: Integer; CapturedPageID: Integer; PageHeight: Double; PageWidth: Double; Path: AnsiString; begin QP := TQuickPDF0716.Create; try UnlockResult := QP.UnlockKey('...'); // Insert trial or paid license key here if UnlockResult = 1 then begin // You can only use the DrawCapturedPage function if the captured page is in the same // document, so first we'll need to merge the two pages that we wish to overlay together // into one document. if dlgOpen.Execute then begin QP.LoadFromFile(dlgOpen.FileName); FileA := QP.SelectedDocument(); end; if dlgOpen.Execute then begin QP.LoadFromFile(dlgOpen.FileName); FileB := QP.SelectedDocument(); end; // After merging FileB is automatically deleted, leaving only FileB which is now a combination of FileA and FileB QP.SelectDocument(FileA); QP.MergeDocument(FileB); // Capture the second page in the merged document CapturedPageID := QP.CapturePage(2); // Now select the first page and retrieve its height and width QP.SelectDocument(FileA); QP.SelectPage(1); PageHeight := QP.PageHeight(); PageWidth := QP.PageWidth(); // Draw the captured page onto the currently selected page QP.DrawCapturedPage(CapturedPageID, 0, PageHeight, PageWidth, PageHeight); // Save the stitched file to disk if dlgSave.Execute then begin Path := dlgSave.FileName; end; QP.SaveToFile(Path); end; finally QP.Free; end; end; ------------ Obviously if the two pages don't have the same dimensions then you'll need to do some tinkering, but if they do, then this code should work quite well. Edited by Rowan - 07 Sep 09 at 2:40AM

mmolenkp Members Profile Find Members Posts Beginner Joined: 26 Feb 13 Status: Offline Points: 6	Post Options Post Reply Quote mmolenkp Report Post Thanks(0) Quote Reply Posted: 26 Feb 13 at 4:24PM
	I took this sample for my own code in Delphi 7 and it works as designed BUT not for all cases. I have a multi page word document and I need to place an overlay pdf page on the back ground of some pages. The first step generate a PDF with microsoft word and use it with this sample, it works correct. When I use OpenOffice 4.3 or LIbre Office 4.0 and then export as PDF it dont work coreect. The stitching works on every page, but when I open the resulting file with acrobat I get an error message. Ik have done some debugging, to isolate the problem: When I captured the first page of the PDF file generated with Openoffice en then SaveToFile the remaining pages. It gives me a file that get an error by acrobat reader. I Have tried this problem with Lib 0811 an the 0912 the same result. My Idee is that Microsoft has put more page information on every page and OpenOffice Not. What can I do ? Thanks for help Mike