mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-11-23 10:11:08 +00:00
112 lines
5 KiB
Markdown
112 lines
5 KiB
Markdown
# GStreamer Legal Issues
|
|
|
|
<!-- FIXME: this entire section seems out of date and a bit weird. No one
|
|
ever asks questions like that any more. Should be made more relevant -->
|
|
|
|
This part of the FAQ is based on a series of questions we asked the FSF
|
|
to understand how the GPL works and how patents affects the GPL. These
|
|
questions were answered by the [FSF lawyers](http://www.fsf.org/), so we
|
|
view them as the final interpretation on how the GPL and LGPL interact
|
|
with patents in our opinion. This consultancy was paid for by
|
|
[Fluendo](http://www.fluendo.com/) in order to obtain clear and quotable
|
|
answers. These answers were certified by the FSF lawyer team and
|
|
verified by FSF lawyer and law professor Eben Moglen.
|
|
|
|
> Can someone distribute the combination of:
|
|
> - GStreamer, the LGPL library
|
|
> - MyPlayer, a GPL playback application
|
|
> - The binary-only Sorenson decoder
|
|
>
|
|
> together in one distribution/operating system? If not, what needs to be
|
|
> changed to make this possible?
|
|
|
|
This would be a problem, because the GStreamer and MyPlayer
|
|
licenses would forbid it. In order to link GStreamer to MyPlayer, you
|
|
need to use section 3 of the LGPL to convert GStreamer to GPL. The GPL
|
|
version of GStreamer forbids linking to the Sorenson decoder. Anyway,
|
|
the MyPlayer GPL license forbids this.
|
|
|
|
If the authors of MyPlayer want to permit this, we have an exception for
|
|
them: the controlled interface exception from the FAQ. The idea of this
|
|
is that you can't get around the GPL just by including a LGPL bit in the
|
|
middle.
|
|
|
|
Note: MyPlayer is a completely fictituous application at the time of
|
|
writing.
|
|
|
|
> Suppose Apple wants to write a binary-only proprietary plugin for GStreamer
|
|
>
|
|
> .. to decode Sorenson video, which will be shipped stand-alone,
|
|
> not part of a package like in the question above. Can Apple distribute
|
|
> this binary-only plugin?
|
|
|
|
Yes, modulo certain reverse engineering requirements in section 6
|
|
of the LGPL.
|
|
|
|
> If a program released under the GPL uses a library that is LGPL, and
|
|
> this library can dlopen plug-ins at runtime, what are the requirements
|
|
> for the license of the plug-in?
|
|
|
|
You may not distribute the plug-in with the GPL application.
|
|
Distributing the plug-in alone, with the knowledge that it will be used
|
|
primarily by GPL software is a bit of an edge case. We will not advise
|
|
you that it would be safe to do so, but we also will not advise you that
|
|
it would be absolutely forbidden.
|
|
|
|
> Can someone in a country that does not have software patents
|
|
> distribute code covered by US patents under the GPL to people in, for
|
|
> example, Norway? If he/she visits the US, can he/she be arrested?
|
|
|
|
Yes, he can. No, there are no criminal penalties for patent
|
|
infringement in the US.
|
|
|
|
> Can someone from the US distribute software covered by US patents
|
|
> under the GPL to people in Norway? To people in the US?
|
|
|
|
This might infringe some patents, but the GPL would not forbid it
|
|
absent some actual restriction, such as a court judgement or agreement.
|
|
The US government is empowered to refuse importation of patent
|
|
infringing devices, including software.
|
|
|
|
> There are a lot of GPL- or LGPL-licensed libraries that handle media
|
|
> codecs which have patents. Take mad, an mp3 decoding library, as an
|
|
> example. It is licensed under the GPL. In countries where patents are
|
|
> valid, does this invalidate the GPL license for this project?
|
|
|
|
The mere existence of a patent which might read on the program
|
|
does not change anything. However, if a court judgement or other
|
|
agreement prevents you from distributing libmad under GPL terms, you can
|
|
not distribute it at all.
|
|
|
|
The GPL and LGPL say (sections 7 and 11): “If you cannot distribute so
|
|
as to satisfy simultaneously your obligations under this License and any
|
|
other pertinent obligations, then as a consequence you may not
|
|
distribute the Library at all.”
|
|
|
|
> So let's say there is a court judgement. Does this mean that the GPL
|
|
> license is invalid for the project everywhere, or only in the
|
|
> countries where it conflicts with the applicable patents?
|
|
|
|
The GPL operates on a per-action, not per-program basis. That is,
|
|
if you are in a country which has software patents, and a court tells
|
|
you that you cannot distribute (say) libmad in source code form, then
|
|
you cannot distribute libmad at all. This doesn't affect anyone else.
|
|
|
|
> Patented decoding can be implemented in GStreamer either by having a
|
|
> binary-only plugin do the decoding, or by writing a plugin (with any
|
|
> applicable license) that links to a binary-only library. Does this
|
|
> affect the licensing issues involved in regards to GPL/LGPL?
|
|
|
|
No.
|
|
|
|
> Is it correct that you cannot distribute the GPL mad library to decode
|
|
> mp3's, *even* in the case where you have obtained a valid license for
|
|
> decoding mp3?
|
|
|
|
The only GPL-compatible patent licenses are those which are open
|
|
to all parties posessing copies of GPL software which practices the
|
|
teachings of the patent.
|
|
|
|
If you take a license which doesn't allow others to distribute original
|
|
or modified versions of libmad practicing the same patent claims as the
|
|
version you distribute, then you may not distribute at all.
|