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title: "Preflight capability map" description: "What the lint-pdf engine detects today across print production, packaging, accessibility/PDF-UA, and AI regulatory checks — mapped to the built-in profiles that enable each surface." group: "Reference" order: 10

LintPDF preflight capability map (engine)

This document maps what the lint-pdf/ engine can detect today to the major preflight “surfaces” (print production, packaging, accessibility/PDF-UA, and AI regulatory checks), and to the builtin profiles that enable them.

Profiles (builtin)

  • lintpdf-default.json
    • Enabled: LPDF_*, PDFX4-*, PDFX1A-*, PDFA-*, AI_*
    • Conformance target: pdfx4
    • Notes: AI enabled (categories=["all"])
  • lintpdf-strict.json
    • Enabled: LPDF_*, PDFX4-*
    • Conformance target: pdfx4
    • Notes: stricter DPI + small-text thresholds; AI disabled (no AI_*)
  • lintpdf-advisory-only.json
    • Enabled: LPDF_* (with max_severity="advisory")
    • Conformance target: none
    • Notes: good for “non-blocking” runs; explicitly disables PDFX4-*

Engine pipeline (what runs)

The main pipeline is PreflightOrchestrator.run() in src/lintpdf/profiles/orchestrator.py:

  1. Parse PDF (pikepdf)
  2. Build semantic model (pages, resources, fonts, images, boxes)
  3. Interpret content streams into events (text/image/path paint events)
  4. Run engine analyzers (deterministic LPDF_*)
  5. Run built-in conformance validators (PDF/X, PDF/A variants) where configured
  6. Run veraPDF conformance (PDF/X, PDF/A, PDF/UA) when configured and opted-in
  7. Run OCR text-region pass (best-effort; enables outlined-text heuristics)
  8. Run AI analyzers (if profile enables AI_* and profile.ai.enabled)
  9. Filter/override findings per profile rules; enrich bboxes from events

Detection domains (non-AI, LPDF_*)

Print production & structural

  • Page boxes / bleed / safety / dimensions: PageGeometryAnalyzer
    • IDs: LPDF_BOX_* (incl. LPDF_BOX_005, LPDF_BOX_006, LPDF_BOX_010)
  • Fonts: FontAnalyzer
    • IDs: LPDF_FONT_*
  • Images / effective DPI / compression: ImageAnalyzer
    • IDs: LPDF_IMG_*
  • Transparency / blend-space: TransparencyAnalyzer
    • IDs: LPDF_TRANS_*
  • Overprint: OverprintAnalyzer
    • IDs: LPDF_OVER_*
  • ICC profiles / output intent: IccProfileAnalyzer
    • IDs: LPDF_ICC_*
  • Metadata / XMP / language: MetadataAnalyzer
    • IDs: LPDF_META_*, LPDF_LANG_*, LPDF_XMP_*
  • Structure / encryption / interactive features: StructureAnalyzer, DocumentAnalyzer, AnnotationAnalyzer
    • IDs: LPDF_STRUCT_*, LPDF_DOC_*, LPDF_ANNOT_* (varies by module)

Color, ink coverage, and prepress heuristics

  • Ink coverage: InkCoverageAnalyzer
    • IDs: LPDF_INK_*
  • Spot colors: SpotColorAnalyzer + spot-name analyzers
    • IDs: LPDF_SPOT_*, LPDF_SPOT_NAME_*
  • Process/pure-K/rich-black classification:
    • ColorAnalyzer (IDs: LPDF_COLOR_009, LPDF_COLOR_010, …)
    • AdvancedColorAnalyzer (IDs: LPDF_ADV_* incl. LPDF_ADV_005)

Packaging-specific

  • PackagingAnalyzer (only conditionally added when profile id contains "packaging")
    • IDs: LPDF_PKG_*
  • Dieline family: DielineIso19593Analyzer, DielinePerfIndicatorAnalyzer, plus orchestrator dieline detection attachment
    • IDs: AI_DIE_* (AI) and LPDF_* packaging geometry checks depending on analyzer
  • Seal zone / keepout: SealZoneKeepoutAnalyzer
    • ID: LPDF_BOX_SEAL_ZONE_VIOLATION

Barcodes

  • BarcodeAnalyzer
    • 1D candidate detection + grading: LPDF_BARCODE_001–013, 019–031
    • 2D fill-grid heuristics: LPDF_BARCODE_014–018

Conformance (PDF/X, PDF/A, PDF/UA)

  • Built-in validators (engine-side) run based on profile.conformance:
    • pdfx4, pdfx1a, pdfx3, pdfa1b/2b/3b
  • veraPDF runner (src/lintpdf/conformance/verapdf_runner.py) runs when configured and emits:
    • LPDF_PDFX_CONF (PDF/X)
    • LPDF_PDFA_CONF (PDF/A)
    • LPDF_UA_CONF (PDF/UA-1; only when profile opts into LPDF_UA_*)

AI analyzers (AI_*)

AI analyzers are registered in src/lintpdf/ai/** and run only when the profile enables AI.

Common families:

  • Regulatory compliance: AI_EU1169_*, AI_PHARMA_*, AI_FDA_*, AI_GHS_*, AI_COSM_*, LPDF_TOBACCO_* (implemented as AI analyzer)
  • Accessibility (contrast): AI_WCAG_*

Notable gaps / footguns to watch

  • “Enabled pattern” != “actually runs”: some analyzers are conditionally added (e.g. packaging analyzer depends on profile id, not checks pattern).
  • veraPDF “silent skip”: when veraPDF is unreachable, findings are suppressed (good for resilience, but you need metadata to know it didn’t run).
  • Outlined-text / hidden-layer text: any rule that relies on page.content_stream string presence can miss/gate incorrectly unless OCR/text-region fallback is used.