It offers the functionality to import bibliographic data from PDFs. JabRef is an MIT-licensed open-source BibTeX and BibLaTeX bibliographic manager actively developed on GitHub. I am one of the authors of JabRef and like open source development.
This solution is not perfect, but might be a good start. I also found exiftool.ĭisclaimer: This is a short version of an answer posted at tex.sx. dLib, pdfextract and TeamBeam which seem to have scholarly papers associated with them and therefore seem to be misssed by the JISC review (or developed afterwards). This blog reviews the metadata extraction performance of WizFolio. Papers also seems to do metadata extraction. This answers to this TeX.SX question suggests BibDesk and JabRef do metadata extraction. This list seems to leave out some other solutions, although it is possible that they rely on the same underlying technology. The JISC ConnectedWorks project produced a review document that considered Zotero, Mendeley, Google Scholar, CB2BIB, Metadata Extraction Tool, pdfssa4met, pdfmeat, GNU libextractor, FITS, Apache Tika, XPDF, PDFTOHTML, pdf2xml, CiteSeerX, and Paperpile.
I cannot find any documentation on the meeting and anything else that came out of it. This SO answer suggests that the 2010 London Dev8D meeting, whatever that is, ran a contest for meta data extraction and resulted in pdfssa4met.
NB: My answer does not differentiate between open and closed sourced projects and I have not used any of the seemingly big list of solutions.