Using text pixelation or blurring has recently become a popular way to protect documents because of its aesthetic appeal over black boxes. The problem with this type of “redaction” is that since the text is not actually removed software can be used to easily decode or recover the blurred or pixelated text.
Take a look at these articles showing why it’s a bad idea to use pixelation or blurring for redaction:
- http://gizmodo.com/why-you-should-never-use-pixelation-to-hide-sensitive-t-1610206920
- https://dheera.net/projects/blur
- https://cseweb.ucsd.edu/~hovav/dist/redaction.pdf
In fact, with with just a 8 x 8 pixelated photo of a person’s face, software can be used to recreate a higher quality image accurately representing the actual individual. See Google algorithm constructs faces from 8×8 pixel photos
This is why it’s extremely important to use the proper redaction tools, like those provided in PDF Studio, that will remove the underlying content rather than only blurring it. PDF Studio allows you to Properly Redact PDFs on Windows, Mac, or Linux as well as check to make sure your PDF Document is Redacted Correctly.
