Thursday, November 22, 2012

Create anonymous pdf file

I often use LibreOffice (previously I used, not sure where these two are heading to) to create a text and its Export to PDF... function to create the corresponding pdf file.

Today I wanted to create an anonymous pdf file. It was the copy of a text where I had omitted all personal references (name, address, links to personal web sites, etc.) and I also wanted the pdf file to be anonymous in the sense that it shouldn't contain any personal trace.

I'm not sure that I reached 100% anonymity but here is what I found: the Properties section of the pdf file contained a number of references to my name which I had to get rid off one by one.

File: which is the file name. Originally my initials were part of it but I had saved the file without it already using a neutral file name.

Title: often I give documents a title in  File -> Properties.. . In the Description tab there is a Title entry where in this instance I had put my name too which I needed to remove.
(My first try was the LibreOffice Export to PDF... dialog. There is a tab User Interface with a sub section Windows which shows a tick box Display document title which is ticked by default. After removing the tick the title had disappeared from the the top of the pdf window but it still showed in the pdf properties.)

Author: I have set my profile in LibreOffice preferences User Data e.g. name, address etc. I use it to include parts of it whenever necessary. In order to exclude this information from showing up in a pdf file I had to change the LibreOffice file's properties.
Go to File -> Properties.. and choose the General tab. There is a tick box Apply User Data which is ticked by default. Removing the tick will prevent from user data being used. The LibreOffice file needs to be first saved and then exported again.

Location: since I usually create and save files on my system under my account (which contains my full name) it showed as  Macintosh HD:Users:fullname:Documents so I had to find an anonymous place and I chose /Users/Shared.

Since I'm not a pdf expert there might be other (maybe hidden) references somewhere in the pdf file. I'd love to know.