How to fix PDF-19
No PDF/A output intent for the device colours used
A check of the PDF of a ZUGFeRD or Factur-X invoice, not of its XML. It runs when you upload a PDF; the embedded XML then gets the XSD and EN 16931 checks (XRechnung: also the KoSIT rules). Check your PDF with the ZUGFeRD validator or the Factur-X validator. What the PDF check covers.
PDF/A-3 (basic check). This is one of a few basic PDF/A checks. They are not a full PDF/A validation: rules such as CIDSet, transparency or tagged structure are not checked. For a full PDF/A-3 check, run the PDF through veraPDF.
What this rule checks
The pages use device colours (DeviceGray, DeviceRGB or DeviceCMYK), so PDF/A requires an output intent in the catalog: /OutputIntents with /S /GTS_PDFA1 and an ICC profile (/DestOutputProfile). Default colour spaces (DefaultGray, DefaultRGB, DefaultCMYK) on the page are accepted instead. Content streams are scanned in a basic way only.
How to fix it
Add an sRGB output intent (GTS_PDFA1 with an sRGB ICC profile) when creating the PDF/A.
Related rules
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