okular – universal document viewer

okular is a powerful universal document viewer based on KPDF for KDE 4 with a plugin system.

okular combines the excellent functionality of KPDF with the versatility of supporting different kind of documents, including PDF, Postscript, DjVu, CHM, and others.

Its development began as part of Google’s Summer of Code program.

Features include:

  • Thumbnails.
  • Table of Contents.
  • Links and hyperlinks.
  • Presentation mode.
  • Customizable view.
  • Text extraction.
  • Multicolumns view.
  • Page rotation.
  • Annotations and Bookmarks.
  • Forms support.
  • Embedded files in documents.
  • Multimedia support.

Formats supported:

  • Portable Document Format (PDF) with the Poppler backend.
  • Postscript with the libgs backend.
  • Tagged Image File Format (TIFF) with the libTIFF backend.
  • Microsoft Compiled HTML Help (CHM) with the libCHM backend.
  • DjVu with the DjVuLibre backend.
  • Images.
  • DeVice Independent (DVI) – the output format of the TeX typesetting software.
  • XML Paper Specification (XPS) – a document storage and viewing specification developed by Microsoft.
  • Open Document Format (ODF) – implemented by the OpenOffice.org office suite.
  • FictionBook – an open XML-based ebook format.
  • Comicbook – a format used to distribute online comics.
  • Plucker.

Website: okular.kde.org
Support: FAQ
Developer: Okular developers
License: GNU GPL v2


okular is written in C++. Learn C++ with our recommended free books and free tutorials.

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