Export writer document to PDF with another than the default PDF-version

Question

For a few month I am working with Libreoffice 7.4. I am trying to get a PDF with PDF-version 1.5 (because LaTeX still does not accept 1.6 for input).

I am using a command like this as described in this issue by Mike Kaganski:

soffice --convert-to pdf:writer_pdf_Export:{"SelectPdfVersion":"type":"long","value":"15"}} %1

where %1 is a fully qualified writer document (odt). This produces the correct pdf, but always with PDF-spec 1.6. Changing the value in the command to anything has no effect.

By the way, using the exact syntac as in the link, ie 'pdf:writer_pdf...}}' produces not a *.pdf but a *.'pdf.

What am I doing wrongly? Thanks for any help.

Answer 1

Thanks, K J. Though this is not an answer to my question, it led into the right direction (and thus is even better than an answer). It's certainly true that downgrading any document to a lower version is or might be dangerous.

The problem is, however, that \pdfminorversion only works for PdfTeX and not LuaTeX.

According to the answers found here for LuaTeX (and likely XeTeX, I didn't check), you have to set in the preamble of a project either

\pdfvariable minorversion=6

or

\directlua{pdf.setminorversion(6)}

(the latter is not likely to work with XeTeX).

So I still don't know how to effectively (versus theoretically – if someone knows an answer to this he is still wellcome) downgrade a PDF, but nontheless my actual problem is solved.