Quartz-2D : spotting text other the main text in PDF book pages

Question

I would like to know if it is possible (Quartz2D) to programmatically recognize and handle the text above (or below) in a PDF page that shows page number and paragraph title or other information to know where you are in the book. Is it just text like the main text in the page or can be somehow distinguished?

Answer 1

The page number (if printed on the page) is no different to any other text on the page (there are other kinds of page numbers in a PDF file however).

Some kinds of PDF (PDF/A-1a, 'tagged' PDF) do have things like page numbers and titles marked in a separate way, but in the general case PDF files are neither of these and the page number or titles are indistinguishable from the remainder of the text.