Teknisk artikel

HotPDF: PDF/A, PDF/X, and PDF/UA validation in Delphi

HotPDF är ett nativt VCL PDF-bibliotek för Delphi- och C++Builder-program som behöver direkt PDF-skapande och redigering, formulär, annoteringar, kryptering, digitala signaturer, Unicode-teckensnitt, standardmedveten utdata och preflight-rapporter utan extern PDF-runtime.

Den här artikeln är skriven för teams that deliver archival, print, or accessibility-sensitive PDF output from Delphi applications. Den behandlar PDF/A, PDF/X, and PDF/UA validation som produktionsnära dokumentteknik, inte som ett isolerat komponentanrop.

Den praktiska risken är att a document can pass a visual review while missing fonts, output intents, tagged structure, metadata, or accessibility semantics required by the target standard. Därför behöver flödet ett skrivet kontrakt, observerbar diagnostik och realistiska regressionsfiler.

Arkitekturbeslut

Select the standard before generating pages. target profile and conformance level for each output channel / font embedding, color profile, metadata, and transparency policy

  • target profile and conformance level for each output channel
  • font embedding, color profile, metadata, and transparency policy
  • tagging, reading order, alternate text, and artifact treatment
  • whether validation warnings block release or require documented waivers

Implementeringsflöde

Use preflight findings as engineering requirements. The order below keeps the workflow reviewable for Delphi and C++Builder teams.

  1. select the compliance profile before creating the first page object
  2. configure fonts, images, color spaces, metadata, and tagging around that profile
  3. run preflight after generation and parse findings into actionable categories
  4. fix the document source instead of patching the PDF when the issue is template-owned
  5. save the validation report with the output package or support evidence

Valideringsbevis

Validation artifacts for release and support. Keep these fields with the output or support record.

  • profile name, validator version, pass or fail status, and issue severity counts
  • font, color, metadata, tag-structure, and annotation findings
  • waiver owner and business reason for every accepted warning
  • sample output opened in the target archive, print, or accessibility workflow

Compliance choices affect layout and content

PDF/A, PDF/X, and PDF/UA optimize for different guarantees. A single document may not satisfy every profile without tradeoffs in color management, interactivity, transparency, tagging, or embedded content.

Operational metrics to watch

The first release should expose enough metrics to prove the workflow is healthy under real files, not only under curated samples.

  • count and rate for profile name, validator version, pass or fail status, and issue severity counts
  • warning trend for interactive forms and JavaScript may conflict with archival profiles
  • latency of the stage that must select the compliance profile before creating the first page object
  • profile usage for target profile and conformance level for each output channel

Engineering review notes for PDF/A, PDF/X, and PDF/UA validation

Use these review notes to make sure the feature has moved beyond a demo and can be defended during release, support, and customer escalation.

  • Decision: target profile and conformance level for each output channel. Implementation pressure point: configure fonts, images, color spaces, metadata, and tagging around that profile. Acceptance evidence: waiver owner and business reason for every accepted warning. Regression trigger: third-party template assets often introduce fonts or transparency outside policy
  • Decision: font embedding, color profile, metadata, and transparency policy. Implementation pressure point: run preflight after generation and parse findings into actionable categories. Acceptance evidence: sample output opened in the target archive, print, or accessibility workflow. Regression trigger: interactive forms and JavaScript may conflict with archival profiles

Gränsfall

  • interactive forms and JavaScript may conflict with archival profiles
  • print-ready color requirements do not automatically satisfy accessibility needs
  • tagged PDF repair late in the process is expensive and error-prone
  • third-party template assets often introduce fonts or transparency outside policy

Delphi / C++Builder notes

HotPDF Component should sit behind a small service boundary that receives files, streams, profiles, and credentials, then returns output paths, warnings, metrics, and validation status. Important terms include PDF/A, PDF/X, PDF/UA, preflight, output intent, tagged PDF.

Delphi-kodexempel

Följande Delphi-skiss visar en praktisk servicegräns för detta ämne. Håll policykontroller, loggning och validering utanför det smala produktanropet så att arbetsflödet går att testa.

procedure ExportStandardsAwarePdf(const OutputFile: string; const ProfileName: string);
var
  Pdf: THotPDF;
  Report: string;
begin
  Pdf := THotPDF.Create(nil);
  try
    Pdf.FileName := OutputFile;
    ConfigureStandardsProfile(Pdf, ProfileName);
    Pdf.BeginDoc;
    WriteTaggedContent(Pdf);
    Pdf.EndDoc;
    Report := Pdf.CreatePreflightReport(OutputFile);
    FailBuildOnPreflightErrors(Report);
  finally
    Pdf.Free;
  end;
end;

Produktionschecklista

  • Run the workflow on an empty file, a normal customer file, and a worst-case file
  • Open the generated PDF with the target viewer, validator, printer, or downstream application
  • Log product version, profile version, input hash, output path, elapsed time, and warning count
  • Keep passwords, certificates, temporary files, and customer data under explicit retention rules
  • Add regression documents when a customer file exposes a new edge case

Product documentation

HotPDF Component