How to set Natural Language Specification

Something new?

I'm trying wptools + wpdf trial, but I don't find the way to put /Lang into /Type/Catalog part of pdf like this

<<
/Type/Catalog
/Pages 7 0 R
/ViewerPreferences<</DisplayDocTitle true>>
/MarkInfo <</Marked true>>
/StructTreeRoot 11 0 R
/Metadata 2 0 R
/OutputIntents 14 0 R/PageMode/UseNone
/Lang(IT)

I tried with

WPPDFProperties1.PDFPrinter.Info.Strings.Add('/Lang= (IT)');

but this is put in this part of the document

Thanks

Daniele

<<
/Creator(Producer)
/Author(Daniele Muratori)
/Title(Created with wPDF DEMO by WPCubed GmbH - http://www.wpcubed.com)
/Subject(Soggetto)
/Keywords()
/CreationDate(D:20240711174404Z)
/ModDate(D:20240711174404Z)
/Producer(wPDF5 by WPCubed GmbH )
/Lang (IT)

and Adobe Reader don't display the language correctly and so the pdf is not validating againt the w3.org PDF16 directive that is fondamental for the PDF/UA standard.

UA = universal accessibility

Thank you for your resporn.

The /Lang entry in the document catalog : https://www.w3.org/TR/WCAG20-TECHS/PDF16.html

That flag cannot be set. Which PDF property tag are you referring to?

How can I set the default language of a PDF? I create it with TWPViewPDFPLUS.SaveToFile.

I think it must be set to the Lang Key in the catalog dictionary.