If you have some PDF files that contain information which should be copied or edited in anyway, then you can use a free tool called PDF Freeze. It is a small tool that can encrypt a PDF file and protect it against copying, editing and printing.
This tool is designed to be used on Windows computers. It does not require any additional software to be installed for it to work. For example, it will work even if you do not have Adobe Acrobat installed on your Windows PC.
PDF Freeze has a small window in which we have all the features and options available. The very first thing that we have to do is choose a PDF file by clicking on the Browse button. This is the PDF file that you are going to protect against unwanted copying or printing.
The next thing that we can choose is the DPI level of the PDF file. There are many DPI levels that we can pick from – very low, low, normal, high, best or custom. In case you are wondering, why DPI level is being used, this tool converts all the pages into the images first and then prepares the PDF file. This way nobody can select and copy the text from the PDF. The DPI setting is used when generating the images.
There is an option for selecting the type of encryption cipher to be used. We can choose from 40-bit RC4, 128-bit RC4, 128-bit AES, and 256-bit AES. We can also decide not to encrypt the document or leave the original PDF encryption settings as they are.
We can also select the type of protection that we are going to get. We can choose one or more type of protections from prohibit printing, prohibit copying and prohibit editing. Clicking on the Freeze button in the toolbar finishes the task in seconds.
There is one drawback of using PDF Freeze – the search text function no longer works for the resulting PDF files. This is because the text content has been converted into the image files.
You can download PDF Freeze from https://www.pdfarea.com/pdf-freeze.htm.