ValidatePdfUa method

Inspects the currently open PDF for PDF/UA-1 compliance markers and returns a structured result with the detected conformance level plus the set of specific issues found.

ValidatePdfUa walks the open document looking for the PDF/UA-1 file-format markers defined by ISO 14289-1:2014:

• An XMP metadata stream with pdfuaid:part = 1 and the matching pdfaExtension:schemas description (§5).
• The mandatory dc:title entry inside the XMP packet (§7.1).
• A StructTreeRoot in the catalog or somewhere in the file (§7.1) — required so the document can carry tagging at all.
• Catalog /MarkInfo << /Marked true /Suspects false >> (§7.1).
• Catalog /ViewerPreferences << /DisplayDocTitle true >> (§7.1).
• Catalog /Lang with a BCP 47 language tag (§7.2).
• Trailer /ID array and the absence of encryption.
• xmp:CreateDate / xmp:ModifyDate (recommended for Info/XMP parity).

The result is a TPdfUaValidationResult record:

• Conformance — the detected level: puc1 (PDF/UA-1 identifier found), pucNone (no PDF/UA marker), or pucUnknown (parse failed).
• Issues — a TPdfUaValidationIssues set containing zero or more values: pvuaiMissingXmpMetadata, pvuaiMissingPdfUaIdentifier, pvuaiMissingExtensionSchema, pvuaiMissingDcTitle, pvuaiMissingStructTreeRoot, pvuaiMissingMarkInfo, pvuaiSuspectsTrue, pvuaiMissingDisplayDocTitle, pvuaiMissingLang, pvuaiEncryptionPresent, pvuaiMissingTrailerId, pvuaiMissingXmpDates.

ValidatePdfUa is a read-only inspection — it does not modify the document and is safe to call repeatedly. Use it before handing a PDF off to an archive system or accessibility checker to surface non-compliance to the operator. For the common "is this PDF/UA-1?" check that doesn't need the issue list, prefer the lighter-weight PdfUaConformance property.

• ValidatePdfUa is a file-format-level inspection — it does not enforce content-level PDF/UA rules (Figure /Alt text, Form widget tagging, table /TH /Scope attributes, font embedding completeness, ToUnicode CMaps, etc.). For a full validator pair this method with an external tool such as PAC 2024 or axesPDF.
• Calling ValidatePdfUa on an inactive document returns a record with Conformance = pucUnknown and an empty Issues set.
• The validator only flags pvuaiSuspectsTrue when an explicit /Suspects true appears in /MarkInfo. Documents that lack the /Suspects key entirely are considered compliant on that point (the spec only forbids true).
• If the source has /ViewerPreferences as an indirect reference (N 0 R) that does not contain /DisplayDocTitle, the validator reports pvuaiMissingDisplayDocTitle — but SaveAsPdfUa does not rewrite the referenced object. Adjust the source's ViewerPreferences before calling SaveAsPdfUa in that case.

PdfUaConformance, SaveAsPdfUa, SaveAsPdfUaToStream, IsTagged, ValidatePdfA