Resolution of Ambiguities – the PDF Validation TWG’s work-product

As reported earlier, the veraPDF project was introduced to the ISO committee managing PDF/A in April, 2015.In that meeting, DualLab’s Boris Doubrov, PDF Association member and the lead technical contractor on the veraPDF project, presented 4 questions generated by the PDF Validation Technical Working Group (TWG), the group responsible for approving veraPDF test-suite files and project software.The ISO committee in question, ISO TC 171 SC 2 WG 5 is developing a document currently known as “PDF/A-next” the end-product of which is likely to become the next part of ISO 19005, the PDF/A specification. The questions generated by the TWG, therefore, are valuable for two reasons:

  • They provide an opportunity to remove the ambiguity in a future part of PDF/A, and
  • although the committee has previously stated that no corrigenda will be published for existing parts of PDF/A, in accepting these corrections, the ISO committee may be seen to be implicitly resolving the ambiguities in the most formal available sense, so
  • the ISO’s committee’s acceptance of a given resolution allows the industry to address the matter on their own terms, but with confidence in a fixed point of reference.

In the most recent meeting, held in Basel, Switzerland between November 16-20, 2015, the PDF Validation TWG added 10 more ambiguities to the original list of 4. Together, these 14 issues (and others to be uncovered as the TWG continues to review PDF/A test files) are now known as the PDF/A Resolution of Ambiguities document.

As the test-suite and software move deeper into PDF/A-2 and PDF/A-3 there will, doubtless, be more questions to be resolved. These will be presented at the next meeting of ISO TC 171 SC 2 WG 5, next May in Ghent, Belgium.