I want to convert some JPEG and PNG files to PDF, but I want to do it in a way that the original files are easily recoverable. This is easy for JPEG files: they get embedded directly in an stream object, so you can recover a bit identical copy of them.

while exporting document from Word application to pdf, links in the document are exported as URI(i.e. file://…../other_doc.pdf). In order to validate them somewhere else I need the links to be of “Go to remote” type – according to ISO 32000-1:2008 – https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/PDF32000_2008.pdf
Links generated by Word document look like this:

I’m trying to “manually” build a PDF and i need to use Times New Roman font for Cyrillic text. I read *.ttf file and embedded it in a PDF file: