With another example of improper redaction – this time by US government agencies over airport screening procedures see USA Today http://usat.me/?36993030 – DocsCorp has published a new white paper on redaction within PDF documents.
The whitepaper makes the point that while redacting paper documents is a fairly simple process – get a marker and strike-through the text to redact it – redacting PDF documents is more complicated. PDF documents are constructed in layers. For example, text is on one layer and images on another. Thus, redacting text with opaque objects is not a foolproof method of redaction as you are simply adding another layer, which can be peeled back to reveal what is underneath. To add another layer of complexity to the redaction problem, you need to consider the underlying structure of the PDF.
Depending on how the PDF was generated – ie a Word document converted to PDF, or a scanned document output as a PDF – there may be more than one layer of information that needs to be redacted.
Click the link to download the whitepaper: www.docscorp.com/public/downloadTrial/RedactionWhitepaperPDFT.cfm