PDF and Image Manipulation

The command line provides powerful tools for manipulating PDF and image files, often offering more efficient and scriptable alternatives to graphical applications. This section covers some common utilities.

PDF Manipulation

pdftk (PDF Toolkit)

  • Description: A versatile tool for manipulating PDF files. It can merge, split, rotate, encrypt, decrypt, and more. pdftk is not usually installed by default.

  • Installation:

    • Debian/Ubuntu: sudo apt install pdftk-java
    • CentOS/Fedora: sudo yum install pdftk / sudo dnf install pdftk (may require enabling the EPEL repository first)
    • If pdftk is not available, qpdf (see below) is a good alternative for many tasks.

  • Example Usage:

    pdftk file1.pdf file2.pdf cat output combined.pdf  # Merge multiple PDFs
pdftk input.pdf cat 1-3 output part1.pdf        # Extract pages 1-3
pdftk input.pdf cat 4-end output part2.pdf      # Extract pages 4 to the end
pdftk input.pdf burst output page_%02d.pdf      # Split a PDF into individual pages (page_01.pdf, page_02.pdf, etc.)
pdftk input.pdf rotate 90 output rotated.pdf     # Rotate all pages 90 degrees clockwise
pdftk input.pdf cat 1-endright output rotated.pdf # Rotate all pages 90 degrees clockwise
pdftk input.pdf cat 1-endleft output rotated_left.pdf # Rotate all pages 90 degrees counter-clockwise
pdftk input.pdf cat 1-enddown output upside_down.pdf # Rotate all pages 180 degrees
pdftk input.pdf background background.pdf output output.pdf # apply a background
pdftk input.pdf dump_data output report.txt       # Extract metadata
pdftk secured.pdf input_pw foopass output unsecured.pdf # decrypt a file
pdftk input.pdf output secured.pdf owner_pw foo user_pw baz allow printing # encrypt a file

qpdf

  • Description: qpdf is a command-line tool that does structural, content-preserving transformations on PDF files.
  • Installation:
    • Debian/Ubuntu: sudo apt install qpdf
    • CentOS/Fedora: sudo yum install qpdf / sudo dnf install qpdf
  • Example Usage: 
      qpdf --empty --pages file1.pdf file2.pdf -- out.pdf # Merge PDF files
  qpdf in.pdf --pages in.pdf 1-5 -- out.pdf           # get pages of a file
  qpdf --decrypt input.pdf output.pdf                 # decrypt a file
  qpdf --encrypt user_password owner_password 40bit -- input.pdf output.pdf # encrypt a file