qpdf

问题 I'm working on a python script that processes PDF files, though some of them contain encryption that restricts usage to only printing, which I have to manually remove before I can process them. For that I have been manually using QPDF to remove these restrictions on individual PDF files before running the script (the commands for qpdf are pretty simple...inside the command prompt -> qpdf --decrypt input.pdf output.pdf) My question is - rather than doing this bit manually, is it possible to

问题 When running the checks for my R-package (via devtools::check() ) I face the warning ''qpdf' is needed for checks on size reduction of PDFs . I found this question were it was suggested (if I understood the answer correctly) to run Sys.which(Sys.getenv("R_QPDF", "qpdf")) and see whether qpdf is found or not. In my case this just returns qpdf "" so, I think I didn't install qpdf correctly. Unfortunately it seems to be quite complicated to install qpdf on Windows. My first side question is:

问题 I have many pdfs, which when copied render incorrect text, due to bad fontmap to unicodemapping Something like this : Original - निर्वाचक Rendered when copied : ननरररचक I have gone through various answers : Unable to copy exact hindi content from pdf Read PDF using itextsharp where PDF language is non-English Parsing a pdf(Devanagari script) using PDFminer gives incorrect output [duplicate] I followed this answer and used qpdf to get the desired pagecontentstream , and I got the cmaps , when