Qpdf

QPDF is a command-line program that does structural, content-preserving transformations on PDF files
Homepage:	http://qpdf.sourceforge.net/
License:	Artistic License 2.0
Platforms:	Windows, Linux
Function:	Metadata Extraction,Decryption
Content type:	Document

Description

Description from the project website:

QPDF is a command-line program that does structural, content-preserving transformations on PDF files. (...) It also provides many useful capabilities to developers of PDF-producing software or for people who just want to look at the innards of a PDF file to learn more about how they work.