mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-11-23 10:11:08 +00:00
abe422b141
Original commit message from CVS: reorganizing manual so that concepts are explained before code is shown. needs some proofreading, will get to it.
78 lines
2.6 KiB
XML
78 lines
2.6 KiB
XML
<chapter id="cha-initialisation">
|
|
<title>Initializing <application>GStreamer</application></title>
|
|
<para>
|
|
When writing a <application>GStreamer</application> application, you can
|
|
simply include <filename class='headerfile'>gst/gst.h</filename> to get
|
|
access to the library functions.
|
|
</para>
|
|
<para>
|
|
Before the <application>GStreamer</application> libraries can be used,
|
|
<function>gst_init</function> has to be called from the main application.
|
|
This call will perform the necessary initialization of the library as
|
|
well as parse the GStreamer-specific command line options.
|
|
</para>
|
|
<para>
|
|
A typical program would start like this:
|
|
</para>
|
|
|
|
<programlisting>
|
|
#include <gst/gst.h>
|
|
|
|
...
|
|
|
|
int
|
|
main (int argc, char *argv[])
|
|
{
|
|
...
|
|
gst_init (&argc, &argv);
|
|
...
|
|
}
|
|
</programlisting>
|
|
<para>
|
|
Use the <symbol>GST_VERSION_MAJOR</symbol>,
|
|
<symbol>GST_VERSION_MINOR</symbol> and <symbol>GST_VERSION_MICRO</symbol>
|
|
macros to get the <application>GStreamer</application> version you are
|
|
building against, or use the function <function>gst_version</function>
|
|
to get the version your application is linked against.
|
|
<!-- FIXME: include an automatically generated list of these options. -->
|
|
</para>
|
|
<para>
|
|
It is also possible to call the <function>gst_init</function> function
|
|
with two <symbol>NULL</symbol> arguments, in which case no command line
|
|
options will parsed by <application>GStreamer</application>.
|
|
</para>
|
|
<sect1>
|
|
<title>The popt interface</title>
|
|
<para>
|
|
You can also use a popt table to initialize your own parameters as shown in the next code fragment:
|
|
</para>
|
|
<programlisting>
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
gboolean silent = FALSE;
|
|
gchar *savefile = NULL;
|
|
struct poptOption options[] = {
|
|
{"silent", 's', POPT_ARG_NONE|POPT_ARGFLAG_STRIP, &silent, 0,
|
|
"do not output status information", NULL},
|
|
{"output", 'o', POPT_ARG_STRING|POPT_ARGFLAG_STRIP, &savefile, 0,
|
|
"save xml representation of pipeline to FILE and exit", "FILE"},
|
|
POPT_TABLEEND
|
|
};
|
|
|
|
gst_init_with_popt_table (&argc, &argv, options);
|
|
|
|
...
|
|
</programlisting>
|
|
<para>
|
|
As shown in this fragment, you can use a <ulink
|
|
url="http://developer.gnome.org/doc/guides/popt/"
|
|
type="http">popt</ulink> table to define your application-specific
|
|
command line options, and pass this table to the
|
|
function <function>gst_init_with_popt_table</function>. Your
|
|
application options will be parsed in addition to the standard
|
|
<application>GStreamer</application> options.
|
|
</para>
|
|
</sect1>
|
|
|
|
</chapter>
|