How to make PdfLayer.SetPrint work with PdfStamper? - pdf

Question

I'm adding watermarks on existing PDF using the iText PdfStamper class. And I want these watermarks to be switched to on or off, so I'm using the class PdfLayer.
But I also want these watermarks to be always visible when the file is printed : I'm using the function PdfLayer.setPrint() then.
This is this last step that unfortunately doesn't work as expected.
Here's my code :
PdfReader reader = new PdfReader("C:/Temp/input.pdf");
PdfStamper stamp = new PdfStamper(reader, new FileOutputStream("C:/Temp/output.pdf"));
PdfWriter writer = stamp.getWriter();
PdfLayer layer = new PdfLayer("Watermarks", writer);
layer.setOn(true);
layer.setPrint("Watermarks", true);
BaseFont bf = BaseFont.createFont();
PdfContentByte cb = stamp.getOverContent(1);
cb.beginText();
cb.setFontAndSize(bf, 18);
cb.beginLayer(layer);
cb.showTextAligned(Element.ALIGN_LEFT, "Watermark line 1", 50, 55, 0);
cb.showTextAligned(Element.ALIGN_LEFT, "Watermark line 2", 50, 40, 0);
cb.endLayer();
cb.endText();
stamp.close();
reader.close();
When I check the layer properties from Adobe Reader (version 10), I see that the "Initial State : Print" property stays at "Prints When Visible" while it should be "Always Print".
I also tried creating layers on a new PDF document and there the setPrint() works.
What am I doing wrong ?

Answer 1

I have the same issue. My code want to add a image as watermark on every page of original pdf. And the watermark can only be viewed, not allow to print. I use PdfStamper and PdfLayer.setPrint() too. But it did not work. I read the itext java source and found a way to make it work. Here is code :
PdfWriter writer = stamp.getWriter();
PdfLayer layer = new PdfLayer("Watermarks", writer);
layer.setOn(true);
layer.setOnPanel(false);
layer.setPrint("watermark", false);
writer.addToBody(layer.getPdfObject(), layer.getRef());
It call addToBody after setPrint. This works well.

Answer 2

I have the same problem. As a workaround, you can use new Document and getImportedPage instead of pdfStamper.
Unfortunately, you loose the hyperlink because all pages are converted to images. I tried to use PdfCopy but I reproduced the same issue. I am really interested in a solution allowing me to add a watermark without changing the source file.
Degraded sample solution :
PdfReader pdfReaderS = new PdfReader(filepathS);
Document document = new Document(pdfReaderS.getPageSizeWithRotation(1));
PdfWriter pdfWriterD = PdfWriter.getInstance(document, new FileOutputStream(filepathD));
document.open();
PdfContentByte pdfContentByteD = pdfWriterD.getDirectContent();
BaseFont baseFont = BaseFont.createFont(BaseFont.HELVETICA, BaseFont.WINANSI, BaseFont.EMBEDDED);
int n = pdfReaderS.getNumberOfPages();
PdfLayer pdfLayer = new PdfLayer("Watermark", pdfWriterD);
pdfLayer.setPrint("Print", true);
pdfLayer.setView(visibleScreen);
for (int i = 1; i <= n; i++) {
Rectangle pageSizeS =pdfReaderS.getPageSizeWithRotation(i);
float pageWidth = pageSizeS.getWidth() / 2;
float pageheight = pageSizeS.getHeight() / 2;
float degree = (float)(Math.toDegrees(Math.atan(pageSizeS.getHeight()/pageSizeS.getWidth())));
document.setPageSize(pageSizeS);
document.newPage();
PdfImportedPage pdfImportedPage = pdfWriterD.getImportedPage(pdfReaderS, i);
int rotation = pdfReaderS.getPageRotation(i); //This value can be 0, 90, 180 or 270.
if (rotation == 0)
pdfContentByteD.addTemplate(page, 1, 0, 0, 1, 0, 0);
else if (rotation == 90)
pdfContentByteD.addTemplate(page, 0, -1, 1, 0, 0, pageSizeS.getHeight());
else if (rotation == 180)
pdfContentByteD.addTemplate(page, -1, 0, 0, -1, pageSizeS.getHeight(), pageSizeS.getWidth());
else if (rotation == 270)
pdfContentByteD.addTemplate(page, 0, 1, -1, 0, pageSizeS.getWidth(), 0);
pdfContentByteD.beginLayer(pdfLayer);
pdfContentByteD.beginText();
pdfContentByteD.setFontAndSize(baseFont, policeSize);
pdfContentByteD.setColorFill(col);
pdfContentByteD.showTextAligned(PdfContentByte.ALIGN_CENTER, text, pageWidth, pageheight, degree);
pdfContentByteD.endText();
pdfContentByteD.endLayer();
}
document.close();
pdfReaderS.close();