PDF/A-2

PDF/A-2 is ISO 19005-2, built on PDF 1.7. It exists because PDF/A-1 ruled out features that ordinary documents had started using, so a conversion to part 1 often meant throwing content away. Part 2 keeps the archival guarantees and allows most of it back.

Three profiles cover it, one per conformance level: pdfa.NewProfile2B, pdfa.NewProfile2U and pdfa.NewProfile2A. 2U adds the requirement that text maps to Unicode, and 2A adds a tagged structure on top of that.

Relative to PDF/A-1, part 2 permits transparency and transparency groups, optional content with rules on its configuration, and JPEG 2000 image data. It also adds rules PDF/A-1 had no need for: encryption permissions must not restrict what a conforming reader may do, digital signature dictionaries are constrained, and alternate presentations and the Requirements catalog entry are forbidden.

Embedded files are permitted, with a catch that is the whole reason PDF/A-3 exists. A file specification with an EF entry has to carry F, UF and AFRelationship, and the embedded file’s MIME type has to be application/pdf. Attaching a spreadsheet or an XML invoice to a PDF/A-2 file reports a violation of rule 6.8-4. Part 3 drops that restriction and changes nothing else.

Where to look

The shared mechanics, the full profile list and the conformance levels are covered on the PDF/A section page.