gstreamer/docs/faq/general.xml

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<sect1 id="chapter-general">
<title id="title-general">General</title>
<qandaset defaultlabel="qanda">
<qandaentry>
<question id="general-media-player">
<para>Is GStreamer a media player ?</para>
</question>
<answer>
<para>
No, GStreamer is a development framework for creating applications like
media players, video editors, streaming media broadcasters and so on.
That said, very good media players can easily be built on top
of GStreamer especially when using the high-level object called playbin.
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="general-why-c">
<para>
Why is GStreamer written in C ? Why not C++/Objective-C/... ?
</para>
</question>
<answer>
<para>
We like C. Aside from "personal preference", there are a number of technical
reasons why C is nice in this project:
<itemizedlist>
<listitem><para>C is extremely portable.</para></listitem>
<listitem><para>C is fast.</para></listitem>
<listitem><para>It is easy to make language bindings for libraries written in C.
</para></listitem>
<listitem><para>The GObject object system provided by GLib implements objects in C,
in a portable, powerful way. This library provides for introspection and
runtime dynamic typing. It is a full OO system, but without the syntactic
sugar. If you want sugar, take a look at
<ulink url="http://live.gnome.org/Vala">Vala</ulink>.</para></listitem>
<listitem><para>Use of C integrates nicely with Gtk+ and GNOME. Some people like
this a lot, but neither Gtk+ nor GNOME are required by GStreamer.</para></listitem>
</itemizedlist>
</para>
<para>
So, in closing, we like C. If you don't, that's fine; if you still want to
help out on GStreamer, we always need more language binding people. And if
not, don't bother us; we're working :-)
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="general-applications">
<para>What applications are available for GStreamer ?</para>
</question>
<answer>
<para>
Many media player applications have chosen GStreamer for their backend.
Also a couple of media format conversion tools have been written using the powers of GStreamer.
With the advent of GStreamer-0.10 several media editing applications have been started.
</para>
<para>
For a list of projects, look at the
<ulink url="http://gstreamer.freedesktop.org/apps/">application list</ulink>
on the GStreamer project website.
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="general-format">
<para>Does GStreamer support the format of my media files?</para>
</question>
<answer>
<para>
GStreamer aims to support every format imaginable, but that doesn't mean the
developers have managed to achieve that aim yet. If a GStreamer enabled
application doesn't play back your files, you can help us solve that problem
by <ulink url="http://bugzilla.gnome.org">filing an enhancement request
bug</ulink> for that format. If you have it, please provide:
<itemizedlist>
<listitem><para>links to other players, preferably Open Source and working
on Unix</para></listitem>
<listitem><para>links to explanations of the format.</para></listitem>
<listitem><para>ways to obtain mediafiles in that format to test.
</para></listitem>
</itemizedlist>
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="general-licensing">
<para>
What are the exact licensing terms for GStreamer and its plugins ?
</para>
</question>
<answer>
<para>
All of GStreamer, including our own plugin code, is licensed under the
<ulink url="http://www.gnu.org/licenses/lgpl-2.1.html">GNU LGPL 2.1</ulink> license.
Some of the libraries we use for some of the plugins are however under the
GPL, which means that those plugins can not be used by a non-GPL-compatible
application.
</para>
<para>
As part of the GStreamer source download you find a file called
LICENSE_readme in gst-plugins package. That file contains information in the exact licensing
terms of the libraries we use. As a general rule, GStreamer aims at using
only LGPL or BSD licensed libraries if available and only use GPL or
proprietary libraries where no good LGPL or BSD alternatives are available.
</para>
<para>
From GStreamer 0.4.2 on, we implemented a license field for all of the plugins,
and in the future we might have the application enforce a stricter policy
(much like tainting in the kernel).
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="general-sound-server">
<para>Is GStreamer a sound server ?</para>
</question>
<answer>
<para>
No, GStreamer is not a soundserver. GStreamer does however have plugins
supporting most of the major soundservers available today, including
pulseaudio, ESD, aRTSd, Jack and others.
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="general-platforms">
<para>
Will GStreamer be available for platforms other than Unix ?
</para>
</question>
<answer>
<para>
Depends. Our main target is the Unix platform. It also works on Win32 and Mac OS X,
but it may still be a bit challenging to get everything up and running.
That said, interest has been expressed in porting GStreamer to other platforms and the GStreamer core
team will gladly accept patches to accomplish this.
<!-- Please refer to the
<ulink url="http://gstreamer.net/status/?category=7">
platform support status table</ulink> -->
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="general-gnome">
<para>What is GStreamer's relationship with the GNOME community ?</para>
</question>
<answer>
<para>
While GStreamer is operated as an independent project, we do have a close
relationship with the GNOME community. Many of our hackers consider
themselves also to be members of the GNOME community.
GStreamer is officialy bundled with the GNOME desktop, as lots of packages
(like gnome-media, totem and rhythmbox) are using it.
This does not exclude use of GStreamer by other communities at all, of course.
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="general-kde">
<para>What is GStreamer's relationship with the KDE community ?</para>
</question>
<answer>
<para>
The GStreamer community wants to have as good a relationship as possible
with KDE, and we hope that someday KDE decides to adopt GStreamer as their
multimedia API (planned for KDE 4).
There have been contacts from time to time between the GStreamer community
and KDE and we do already have support for the aRTSd sound server used by KDE.
Also, some of the KDE hackers have created Qt bindings of GStreamer,
made a simple video player and using it in some audio players (JuK and AmaroK).
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="general-my-application">
<para>
I'm considering adding GStreamer output to my application...
</para>
</question>
<answer>
<para>
That doesn't really make sense. GStreamer is not a sound server, so you don't
output directly to GStreamer, and it's not an intermediate API between
audio data and different kinds of audio sinks. It is a fundamental design
decision to use GStreamer in your app; there are no easy ways of somehow
'transfering' data from your app to GStreamer. Instead, your app would have
to use or implement a number of GStreamer elements, string them together, and
tell them to run. In that manner the data would all be internal to the
GStreamer pipeline.
</para>
<para>
That said, it is possible to write a plugin specific to your app that can get
at the audio data.
</para>
</answer>
</qandaentry>
</qandaset>
</sect1>