Poppler is a PDF rendering library based on the xpdf-3.0 code base | Hacker News Reader

Poppler is a PDF rendering library based on the xpdf-3.0 code base

poppler.freedesktop.org

53 pointssusam17 comments

It's used in Okular, which is the only free software I know that you can digitally sign documents with.

It's also used in Evince.

I guess the other (quite complete) open source options are xpdf itself, muPDF (used in Sumatra PDF), pdfium (Chromium's PDF viewer) and pdf.js. I wonder how they compare between each others. Especially muPDF and Poppler.

Also (optionally) in Zathura, my preferred PDF view for its minimalist interface: https://pwmt.org/projects/zathura/

Did you know the mupdf backend allows you to open pdfs and epub? 99% of ebooks are either pdf epub or trivially colorlessly convert to epub. There is reasonable virtue in being able to use a single reader for all books.

Inkscape also offers an option to use Poppler as the renderer engine when importing/exporting PDF documents.

"Please note that xpdf, and thus poppler, is licensed under the GPL, not the LGPL. Consequently, any application using poppler must also be licensed under the GPL." [1]

I hope they have a more forgiving licence. PDFium [2] is Apache License, but its Chromium dependency makes it harder to work with.

[1] https://gitlab.freedesktop.org/poppler/poppler

[2] https://pdfium.googlesource.com/pdfium/

>GPL. I hope they have a more forgiving licence.

Sad state of the modern developer.

> "Consequently, any application using poppler must also be licensed under the GPL."

This is not generally true. If your application e.g. just uses a command line tool like pdftotext it can well have another license than GPL, even a proprietary license.

To clarify: when you say "just uses a command line tool" you mean "uses a program by starting it in the normal way in anther process and communicates via its human interface". No calling into its image.

I'm sure you know this, Rochus, but a naive read if your comment is not clear.

Right. Whether it's a human or a machine readable/operable interface is not relevant. The relevant part is "using a regular interface without linking", as you just do when you use their command line tools.

Poppler and its integration with Emacs via pdf-tools has dramatically improved my PDF reading and annotation powers. Since I started using it about 5 years ago, for the first time in over 30 years I prefer reading and annotating papers in digital form (as opposed to just storing and searching, which happened over 10 years ago). Recently I started using Amazon scribe as well, though I wish it was a more hackable hardware (without Amazon as an intermediate) so I could further optimize my workflows.

I guess the name 'zitsel' was already taken.

Its a nod to the Futurama episode ;)

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