overlay one pdf or ps file on top of another

Question

I have two pdf or postscript files (I can work with either one). What I want to do is merge each page on top of the other so that page1 of document A will be combined with page 1 of document B to produce page 1 of the output document. This isn't something I necessarily want need to do programatically, although that would be helpful.

Any ideas?

Answer 1

You can do this with pdf files using the command line tool pdftk using the stamp or background option.

e.g.

$ pdftk file1.pdf background file2.pdf output combinedfile.pdf

This will only work with a one-page background file. If you have multiple pages, you can use the multibackground command instead.

Answer 2

I had success solving this problem (PDF only and Python) by using pyPdf, specifically the mergePage operation.

From the docs:

# add page 4 from input1, but first add a watermark from another pdf:
page4 = input1.getPage(3)
watermark = PdfFileReader(file("watermark.pdf", "rb"))
page4.mergePage(watermark.getPage(0))

Should be enough to get the idea.

Answer 3

Many of the answers here seem extremely out of date. This is especially so for the accepted answer, which uses pdftk. Pdftk is old (as of this edit, the latest release is from 2013), has terrible error handling, requires old versions of libraries, and is no longer packaged for ubuntu. Nobody in 2022 should be using pdftk for anything if they can possibly avoid it.

Qpdf is a nice open-source program that does many of the same things as pdftk, is still maintained (as of this edit, the latest commit is from 4 days ago) and it can do this task (using either --overlay or --underlay, depending on one's wishes):

qpdf a.pdf --overlay b.pdf -- c.pdf

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[Edited to add] As a further example, here's a bit of ruby code using the prawn library to generate one example way this could be used.

The idea is to generate numbered labels for printing onto some hypothetical label sheet (represented by boxes.pdf — actual dimensions are made up, but could be adjusted to fit an existing template if desired), and to have a version that shows the label dimensions visually, for on-screen review (boxednumbers.pdf), while another version (numbers.pdf) would have just the content to print onto an actual sheet of pre-cut labels.

(Note: Presumably in a real-life situation, boxes.pdf might not be generated, and instead be a downloaded template from a label manufacturer — and the qpdf command-line (as well as the dimensioning constants) would be adjusted accordingly, with the outer Prawn::Document.generate block being removed, paper size possibly being modified, etc.)

#!/usr/bin/env ruby

require 'prawn'
require 'prawn/measurement_extensions'

# various constants to define the size and shape of things:
range = 1..90
columns = 5
col_width = 35.mm
box_height = 15.mm
margin = 2.mm
radius = 2.mm

# this is calculated for now, but it could be set manuallly:
font_size = box_height - 2*margin

# one document for showing the boxes (could use an existing PDF):
Prawn::Document.generate('boxes.pdf', page_size: 'A4') do |boxes|
  # another that places numbers to be printed on top:
  Prawn::Document.generate('numbers.pdf', page_size: 'A4') do |numbers|
    range.each_with_index do |n, i|
      # x and y for columner output:
      x = (i % columns) * col_width
      y = boxes.bounds.top - (i / columns) * box_height
      # sizes of the boxes inside the columns:
      width = col_width - margin
      height = box_height - margin
      # draw round rectangles in the boxes PDF:
      boxes.stroke do
        boxes.rounded_rectangle [x, y], width, height, radius
      end
      # draw numbers in the numbers PDF:
      numbers.bounding_box [x,y], width: width, height: height do
        numbers.text n.to_s, align: :center, valign: :center, size: font_size
      end
    end
  end
end

# and then ask qpdf to merge them, with the boxes as an underlay:
%x(qpdf --underlay boxes.pdf -- numbers.pdf boxednumbers.pdf)

Answer 4

2022 onwards

PDFTK is still a strong contender for many users with simple cross platform command lines for many tasks.

PDFtk Server does not require Adobe Acrobat or Reader, and it runs on Windows, Mac OS X and Linux.

You will see multiple commands in the other answers. But one drawback is that it needs to be licensed for distribution.

A commercial license is required to distribute PDFtk with your commercial product.

Another daily updated cross platform Solution is GhostScript (but Windows binaries are often bi-annual) and it too requires a commercial license.

Its primary strength is the ability to merge nominated pages from both PostScript AND PDF along with other formats not handled by PDFTK. However it does not profess to be the optimum PDF merge tool. Again there are many well documented ways in StackOverflow answers to use that grandfather application for different combinational tasks, but may requires more complex approaches than a quick one liner, and many users will combine PDL or PS handling with PDFTK (above) for final overlay.

So what is updated frequently, and is available for commercial use and does the task in a single call? The answer is QPDF (licensed under the Apache License, Version 2.0), which has both overlay and underlay options options with too many many other abilities to list, but is PDF only.

At its simplest one method is to write a new page from 2 others lets say just page 1, and not changing either source. The downside is that with so many options including passwords the syntax can become complex, good news is it may be overhauled in next version 11. Also beware it does not like file names with spaces.

First generate a new empty input file with page 1 from file1 (easy enough)

qpdf --empty --pages "file1.pdf" 1 -- "output.pdf"

Now overlay that with first page of file2 (this is a bit more complicated)

qpdf output.pdf --overlay "file2.pdf" --from=1 -- --replace-input

The commands can be combined in one simpler line and for this example lets use page 2 of file 1

qpdf --empty --pages "file1.pdf" 2 --  --overlay "file2.pdf" --from=1 -- "output2.pdf"

You will also need to be aware that mixing page sizes will work however perhaps not as expected so second on first is centred and reduced to fit.

Answer 5

PDFbox for Java supports a Overlay class which allows to merge PDFs this way. See this answer: Watermarking with PDFBox

However, both PyPDF2 and PDFbox have been unreliable in my experience, but perhaps this is helpful for someone.

Answer 6

If you're dealing with only postscript, chances are the only 'pagebreaks' are the 'showpage' operator.
In which case you can simply grab the postscript data from the beginning of file one to the first instance of 'showpage', do the same with the other file, then concatenate these 2 chunks of postscript to create your new page.

If the 2 files are only one page, then you may be able to simply join the 2 files.

Answer 7

Aspose.Pdf.Kit with thePdfFileStamp class can do this, too. It works most of the time correctly.

Answer 8

I used the Mac OS tool PDFClerk Pro. I imported the PDF pages, then merged them with the option "Merge Pages (Stacked)." It really impressed me.

Answer 9

For OS X there is PDF letterhead. Doesn't do anything else than just overlaying PDF's. https://itunes.apple.com/us/app/pdf-letterhead/id976548033?mt=12

Answer 10

You could convert both pdfs into images and overlay one on top of the other layer like.

A suitable graphics library that you could use this would work.

Watermark suggestion above has great potential too as long as you don't run into issues in your language or graphics/pdf library of choice.

Answer 11

VeryPDF PDF Editor has a PDF Overlay function, look at this web page,

http://www.verypdf.com/wordpress/201304/how-to-overlay-pdf-to-another-pdf-35885.html