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Saving the trees - PDF signatures

How to stick a signature graphic into a PDF file, without having to print it first:

A word of warning first

Don't stick your signature into a MS Word document, since anyone with 2 brain cells can alter it.

Also don't use your usual signature - Make a special scrawl for office use.

Print the file to PDF with Foxit Reader

If the file isn't in PDF format already, open your MS Office document with MS Word on Windows.
Print to a file and select PDF format.

If you cannot print to a PDF, install Foxit Reader:

Make a signature graphic with transparent background using Gimp

Make a signature graphic with transparent background:
Take a pen, scrawl on a piece of paper.
Scan it.

Use a real computer - Linux, BSD or Mac:
apt install gimp xournal pdfshuffler

Open the scan file with Gimp
Crop it
Select the white background with the eye dropper
Click Layer, Transparency, Colour to Alpha
Click File, Export, signature.jpg

Annotate the PDF file with Xournal

Open the PDF file with xournal
Click Tools, Image and select the signature.jpg file
Click where you want the signature.
Resize it with the mouse
Click File, Export to PDF and select the original PDF file
Overwrite it.

With xournal, you can annotate a PDF file very nicely.  It is worth learning how to use it.


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