I have been using pdftk to do a lot of scripting with pdf, but I am open to anything that can be done programmatically in linux, ideally through command line or python API.
I would need to change the page numbering in a pdf, i.e. make it so that it starts say, on page 5 instead of 1. The main reason I need the offset is that I will merge this document with others, and ideally I would like each of the documents to carry their own bookmarks and contribute them in the merge.
If I can't do that, one alternative is to strip out the bookmarks (using pdftk dump_data) from the doc, turn them into a python object, then assemble the bookmarks by carrying out the page shifting myself. It's not painless + there's a risk that this I will alter the original documents in unintended ways.
FWIW I did try doing update_info with pdftk, after having tweaked with the output from dump_data. It worked fine for bookmarks, but changing page numbers (as in PageMediaNumber) did not work at all.
Any suggestions?