sane-project-backends/LICENSE

Sat Apr 23 2005

This files attempts to clarify the licensing situation for the SANE
distribution.  In case of doubt, the copyright information contained
in each file overrides what is said here.

SANE consists of three parts each of which has its own licensing
terms:

  * The frontend programs.

    These programs are generally protected by the GNU General Public
    License.  (See file COPYING.)

  * The backend libraries.

    Most backend libraries are protected by the GNU General Public License
    (see file COPYING), but as an exception, it is permissible to link against
    such a library without affecting the licensing status of the program
    that uses the libraries.  For details, see the copyright notice at the
    head of the backend files (e.g., backend/dll.c).

    Note that not all of the backends apply the exception and that some have
    additional licensing constraints.  E.g., the DC210 backend uses JPG code
    that is licensed as described in README.djpeg.

  * The SANE API and network protocol as put forth in the standard document.

    The standard is considered to be in the public domain.  Anyone is free
    to implement SANE interface conforming applications or libraries in
    any way he or she sees fit.

    The standard is maintained at https://gitlab.com/sane-project/standard
    and published at https://sane-project.gitlab.io/standard/.

Frequently Asked Questions about the SANE licensing:

  * Why don't you use the GNU LPGL ?

    The reason SANE isn't licensed under the GNU LGPL is very simple: the
    GNU LGPL didn't exist at the time SANE was first released. So, the SANE
    Exception was added to the GNU GPL.

  * Why don't you relicense SANE, now that the GNU LGPL is available ?

    To relicense the various pieces of code composing SANE, each and every
    copyright holder needs to agree with the relicensing. Unfortunately, some
    of the (original) backend authors cannot be contacted any longer, for
    various reasons; not to mention each and every contributor who sent in a
    patch. This effectively makes it impossible for the SANE Project to
    relicense SANE.