Make a Digital Signature, Use Less Paper

About: A Northern Ireland based maker with a propensity to cause trouble and freshly constructed family.

There are lots of applications out there for editing PDF files, one really handy tool is adding the ability to sign forms without printing them and scanning them just to email them away again. 

However not everyone knows how to make the image, it's really easy though. 

As a suggestion I wouldn't save this image anywhere but a personal flash drive or in a password protected folder, since it could be used to help falsify your identity. You could sign it differently from your written signature and keep track of when you used it, you'll always know which is which and if you signed the document that way, plus if anyone gets the file they'll not be able to hand forge your signature with it.

You'll need:
 - A scanner or camera with macro
 - A pen and paper
 - Photoshop or Gimp (instructions for both included)
 - A PDF editor

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Step 1: Write and Scan

Write you signature a few times on a piece of paper with space around each one, use a black or very dark blue pen. 

Now if you're scanning, use black and white mode, I used photo preset but document will likely work fine too. 

Save the file somewhere. 

If you're taking a photo of the signature make sure it is in focus, evenly lit and from a perpendicular angle to the paper. 

For the photo takers, use black and white. 

Step 2: Open and Crop

Open the file in your chosen program and crop it down to just the signature. 

Clean up any dirt marks with a white brush. 

For photoshop use the crop tool (c) and pull the box down around the signature you want, rotate as needed. 

For gimp use the selection tool then go to image>crop to selection

Step 3: Removing the Background

In photoshop double click the lock symbol on the background layer, click OK to the dialog box that appears. 

Choose the background eraser tool and select discontiguous mode, click on the white and drag the eraser around until all the white is replaced the transparency, you'll see grey and white tiles, that's the default background.  You can also choose the magic eraser and just click on the white. 

In Gimp, you'll need to right click the background layer and hit add alpha channel. 

Now right click>select>by colour and drag on the white. Hit delete or right click>edit>clear.

Your image should now have a clear background and you'll see gray and dark gray tiles behind the signature.

Step 4: Saving the File

You can't just save this as a jpeg, since they don't support transparency. 

Instead we save it as a .PNG format. 

In photoshop click file>save as, choose PNG from the drop down list

In gimp choose to save the file, click the select file type pop up at the bottom and choose PNG from the list. 

The standard settings should be right for this. 

Step 5: Signing the Document

There are a plethora of PDF editors out there. 

In acrobat import the image as a stamp, then add it to signature boxes. 

 For others it might be easier to add as an image, some have a signature function where you choose an image and it keeps that as your signature.

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    9 Discussions

    Anowar Sadat

    3 years ago

    Hi, My name is Anowar, could you kindly make me an elegant and beautiful signature, My email is Please get back to met


    5 years ago on Introduction

    Thanks for sharing! From my point of view, using an electronic signature application would be a better choice because your identity could be authenticated and you won't be worried about your signature image being stolen.

    I used Signority ( free plan to sign some agreements. It is pretty intuitive and easy to use. You can also upgrade your account if you are a heavy user. I like the application so far.


    8 years ago on Introduction

    Hi, very interesting I would vectorize it though, than it can be scaled better and doesn't look so rough.

    Just open it in inkscape, hit shift+alt+b and then ok. This is how my turned out without any further changes (there is of course room for optimisation):

    1 reply

    Illustrator has the same function aswell, I didn't want to add any other layers of complexity to something simple but it's a great tip.

    A vector version would be handy, for scaling as needed but it does need to be a PNG or a GIF file with a transparent background to work with every PDF editor I've come across. Unless you just live with the white box thing...


    8 years ago on Introduction

    One extreme caution when doing this is it's relatively easy to copy a graphic from a PDF file. Even if the file is locked a simple screen capture can make a copy of the signature. That copy can easily be put into other documents as digital forgeries.

    1 reply

    True, I mentioned that issue in the introduction and ways to help guard against this issue, though if it happens it'll only help after the fact. Though this method is handy for in-house and trusted form sending.


    8 years ago on Introduction

    I have done the same thing with a Wacom tablet, but how many people have one - great idea, thanks for sharing.

    1 reply


    I miss having a tablet handy, more for artistic stuff but being able to write on the computer as well as type is really nice.

    Some scanners come with software that lets you choose handwriting, it supposed to be for text recognition but you could probably make it do it with out the imaging stuff here.