The fix-qdf program is part of the qpdf package.
The fix-qdf program reads a PDF file in QDF form and writes out
the same file with stream lengths, cross-reference table entries, and
object stream offset tables regenerated.
For details about fix-qdf and about PDF files in QDF mode, please see
the qpdf manual, which can be found in /usr/local/share/doc/qpdf/qpdf-manual.html or