1 <chapter id="chapter-gstreamer">
2 <title>What is &GStreamer;?</title>
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6 <!-- <sect1 id="section-intro-what"> --><!-- synchronize with PWG -->
8 &GStreamer; is a framework for creating streaming media applications.
9 The fundamental design comes from the video pipeline at Oregon Graduate
10 Institute, as well as some ideas from DirectShow.
14 &GStreamer;'s development framework makes it possible to write any
15 type of streaming multimedia application. The &GStreamer; framework
16 is designed to make it easy to write applications that handle audio
17 or video or both. It isn't restricted to audio and video, and can
18 process any kind of data flow.
19 The pipeline design is made to have little overhead above what the
20 applied filters induce. This makes &GStreamer; a good framework for
21 designing even high-end audio applications which put high demands on
26 One of the the most obvious uses of &GStreamer; is using it to build
27 a media player. &GStreamer; already includes components for building a
28 media player that can support a very wide variety of formats, including
29 MP3, Ogg/Vorbis, MPEG-1/2, AVI, Quicktime, mod, and more. &GStreamer;,
30 however, is much more than just another media player. Its main advantages
31 are that the pluggable components can be mixed and matched into arbitrary
32 pipelines so that it's possible to write a full-fledged video or audio
37 The framework is based on plugins that will provide the various codec
38 and other functionality. The plugins can be linked and arranged in
39 a pipeline. This pipeline defines the flow of the data. Pipelines can
40 also be edited with a GUI editor and saved as XML so that pipeline
41 libraries can be made with a minimum of effort.
45 The &GStreamer; core function is to provide a framework for plugins,
46 data flow and media type handling/negotiation. It also provides an
47 API to write applications using the various plugins.
52 Specifically, &GStreamer; provides
54 <listitem><para>an API for multimedia applications</para></listitem>
55 <listitem><para>a plugin architecture</para></listitem>
56 <listitem><para>a pipeline architecture</para></listitem>
57 <listitem><para>a mechanism for media type handling/negotiation</para></listitem>
58 <listitem><para>over 150 plug-ins</para></listitem>
59 <listitem><para>a set of tools</para></listitem>
64 &GStreamer; plug-ins could be classified into
66 <listitem><para>protocols handling</para></listitem>
67 <listitem><para>sources: for audio and video (involves protocol plugins)</para></listitem>
68 <listitem><para>formats: parsers, formaters, muxers, demuxers, metadata, subtitles</para></listitem>
69 <listitem><para>codecs: coders and decoders</para></listitem>
70 <listitem><para>filters: converters, mixers, effects, ...</para></listitem>
71 <listitem><para>sinks: for audio and video (involves protocol plugins)</para></listitem>
75 <figure float="1" id="section-gstreamer-img">
76 <title>Gstreamer overview</title>
79 <imagedata scale="75" fileref="images/gstreamer-overview.ℑ" format="&IMAGE;" />
85 &GStreamer; is packaged into
87 <listitem><para>gstreamer: the core package</para></listitem>
88 <listitem><para>gst-plugins-base: an essential exemplary set of elements</para></listitem>
89 <listitem><para>gst-plugins-good: a set of good-quality plug-ins under LGPL</para></listitem>
90 <listitem><para>gst-plugins-ugly: a set of good-quality plug-ins that might pose distribution problems</para></listitem>
91 <listitem><para>gst-plugins-bad: a set of plug-ins that need more quality</para></listitem>
92 <listitem><para>gst-python: the python bindings</para></listitem>
93 <listitem><para>a few others packages</para></listitem>