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Or, should/could we use (any) tool to make a bunch of 1-page PDFs, then some other (command-line?) tool to “combine all these 1-page PDFs into one PDF”, which might be a fast and cheap operation?
pdftk
https://www.pdflabs.com/tools/pdftk-server/
(hmm, can’t add image to pdf i don’t think, although can merge and edit metadata on pdf)
combine_pdf
yet another ruby pdf library. is one thing I found to let us edit metadata (ie Info Dictionary) on existing pdf. Could maybe also do other useful stuff for us.
https://github.com/boazsegev/combine_pdf
nope just tried using it to edit metadata on a very large PDF, it used a ton of RAM.
Uncaching on-demand derivatives
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