RUPS is a PDF inspection tool, which we use a lot internally to inspect PDFs received from customers and users. Although RUPS stands for Reading and Updating PDF Syntax, it can't update PDFs. Until recently... We added functionality to update PDF dictionaries allowing us to test out other values in dictionary entries. This functionality was added in RUPS 5.5.0.
In this small tutorial we are going to demonstrate two cases where you could use RUPS to change your PDF syntax and Dictionaries.
Check out the iText RUPS tutorial: use RUPS to change your PDF!