GWG Releases First Universal “Proof of Preflight” Specification

GHENT, Belgium—The Ghent Workgroup (GWG) has released the first free “Proof of Preflight” specification, designed to allow users to easily verify PDF file integrity. When implemented in a software solution, this best practice specification offers users the ability to review a PDF file’s preflight audit trail, including a digital signature, at any time during the design-to-print workflow.

This capability provides users the assurance that they can safely accept a PDF file with a Proof of Preflight. The process verifies which GWG preflight specification was used to preflight the file and also the outcome of the preflight check.

Another feature of the GWG Proof of Preflight specification is its “open” design, making it interoperable across different vendor workflows. GWG designed the digital signature using algorithms which are defined in the PDF 1.7 (or earlier) specification(s), and which are supported in Acrobat as of Acrobat 8. The digital signature complies with all requirements present in the PDF/X-1a and PDF/X-3, and PDF/X-4 standards.

This first version of its free Proof of Preflight specification was developed by the GWG Process Control Subcommittee. This committee is chaired by Andy Psarianos, F E Burman; with contributions from Olaf Drümmer, Callas, (who was instrumental in the specification documentation); Leonard Rosenthal, Adobe; Peter Kleinheider, Callas; Stephane Georges, Dalim; and Stephan Jaeggi, Pre-Press Consulting. The goal of the Process Control subcommittee is to increase the already high level of predictability in PDF workflows by delivering best practice guidelines for the testing and evaluation of PDF reading applications.

The GWG Proof of Preflight specification is available immediately and can be downloaded for free at www.gwg.org.