mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-12-24 09:10:36 +00:00
110 lines
3 KiB
Text
110 lines
3 KiB
Text
|
<chapter id="cha-goals">
|
||
|
|
<title>Goals</title>
|
||
|
|
<para>
|
||
|
|
GStreamer was designed to provide a solution to the current Linux media
|
||
|
|
problems.
|
||
|
|
</para>
|
||
|
|
|
||
|
|
<sect1 id="sec-goals-design">
|
||
|
|
<title>The design goals</title>
|
||
|
|
<para>
|
||
|
|
We descibe what we try to achieve with GStreamer.
|
||
|
|
</para>
|
||
|
|
<sect2 id="sec-goals-clean">
|
||
|
|
<title>Clean and powerfull</title>
|
||
|
|
<para>
|
||
|
|
GStreamer wants to provide a clean interface to:
|
||
|
|
</para>
|
||
|
|
<itemizedlist>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
The application programmer who wants to build a media pipeline.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
The plugin programmer.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
</itemizedlist>
|
||
|
|
|
||
|
|
</sect2>
|
||
|
|
<sect2 id="sec-goals-object">
|
||
|
|
<title>Object oriented</title>
|
||
|
|
<para>
|
||
|
|
Adhere as much as possible to the GTK+ object model. A programmer familiar
|
||
|
|
with GTK+ will be confortable with GStreamer.
|
||
|
|
</para>
|
||
|
|
<para>
|
||
|
|
GStreamer uses the mechanisems of signals and object arguments.
|
||
|
|
</para>
|
||
|
|
</sect2>
|
||
|
|
|
||
|
|
<sect2 id="sec-goals-extensible">
|
||
|
|
<title>Extensible</title>
|
||
|
|
<para>
|
||
|
|
All GStreamer Objects can be extended using the GTK+ inheritance methods.
|
||
|
|
</para>
|
||
|
|
<para>
|
||
|
|
All plugins are loaded dynamically and can be extended and upgraded
|
||
|
|
independently.
|
||
|
|
</para>
|
||
|
|
</sect2>
|
||
|
|
|
||
|
|
<sect2 id="sec-goals-binary">
|
||
|
|
<title>Allow binary only plugins</title>
|
||
|
|
<para>
|
||
|
|
plugins are shared libraries that are loaded at runtime. since all the
|
||
|
|
properties of the plugin can be set using the GtkObject arguments, there
|
||
|
|
is no need to have any header files installed for the plugins.
|
||
|
|
</para>
|
||
|
|
</sect2>
|
||
|
|
|
||
|
|
<sect2 id="sec-goals-performance">
|
||
|
|
<title>High performance</title>
|
||
|
|
<para>
|
||
|
|
High performance is obtained by:
|
||
|
|
</para>
|
||
|
|
<itemizedlist>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
Using glib g_mem_chunk where possible to minimize dynamic memory
|
||
|
|
allocation.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
Connections between plugins are extremely light-weight. Data can travel
|
||
|
|
the pipeline with minimal overhead.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
Provide a mechanism to directly work on the target memory. A
|
||
|
|
plugin can for example directly write to the X servers shared mem.
|
||
|
|
Buffers can also point to arbitrary memory like kernel memory.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
Refcounting and copy on write to minimize the amount of memcpy.
|
||
|
|
Subbufers to efficiently split the data in a buffer.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
Pipelines can be constructed using cothreads to minimize the
|
||
|
|
threading overhead. Cothreads are a simple user-space method for
|
||
|
|
switching between subtasks.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
HW acceleration is possible by writing a specialized plugin.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
</itemizedlist>
|
||
|
|
</sect2>
|
||
|
|
</sect1>
|
||
|
|
</chapter>
|