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Manual updates. fixes to gstxml.c gst_xml_get_element was broken

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Original commit message from CVS:
Manual updates.
fixes to gstxml.c gst_xml_get_element was broken
This commit is contained in:
Wim Taymans 2001-01-08 22:08:40 +00:00
parent 7291b0f7e8
commit 2a4a536fee
13 changed files with 393 additions and 10 deletions
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2
docs/Makefile.am
View file

@ -1,4 +1,4 @@
SUBDIRS = manual fwg gst libs
SUBDIRS = manual fwg gst libs
EXTRA_DIST = random slides manuals.mak

6
docs/manual/components.sgml
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@ -1,11 +1,14 @@
<chapter id="cha-components">
<title>Components</title>
<para>
<application>GStreamer</application> includes components that people can include
in their programs.
</para>
<sect1>
<title>GstPlay</title>
<para>
GstPlay is a GtkWidget with a simple API to play, pause and stop a media file.
</para>
</sect1>
@ -13,6 +16,7 @@
<sect1>
<title>GstMediaPlay</title>
<para>
GstMediaply is a complete player widget.
</para>
</sect1>
@ -20,6 +24,8 @@
<sect1>
<title>GstEditor</title>
<para>
GstEditor is a set of widgets to display a graphical representation of a
pipeline.
</para>
</sect1>

108
docs/manual/queues.sgml
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@ -8,13 +8,13 @@
<para>
A buffer that is sinked to a Queue will not automatically be pushed to the
next connected element but will be buffered. It will be pushed to the next
element as soon as gst_connection_push () is called.
element as soon as a gst_pad_pull () is called on the queues srcpad.
</para>
<para>
Queues are mostly used in conjunction with a <classname>GstThread</classname> to
provide an external connection for the thread elements. You could have one
thread feeding buffers into a <classname>GstQueue</classname> and another
thread repeadedly calling gst_connection_push () on the queue to feed its
thread repeadedly calling gst_pad_pull () on the queue to feed its
internal elements.
</para>
@ -27,6 +27,110 @@
<graphic fileref="images/queue" format="png"></graphic>
</figure>
<para>
The standard <application>GStreamer</application> queue implementation has some
properties that can be changed using the gtk_objet_set () method. To set the
maximum number of buffers that can be queued to 30, do:
</para>
<programlisting>
gtk_object_set (GTK_OBJECT (queue), "max_level", 30, NULL);
</programlisting>
<para>
The following mp3 player shows you how to create the above pipeline using a
thread and a queue.
</para>
<programlisting>
#include &lt;stdlib.h&gt;
#include &lt;gst/gst.h&gt;
gboolean playing;
/* eos will be called when the src element has an end of stream */
void
eos (GstElement *element, gpointer data)
{
g_print ("have eos, quitting\n");
playing = FALSE;
}
int
main (int argc, char *argv[])
{
GstElement *disksrc, *audiosink, *queue, *parse, *decode;
GstElement *bin;
GstElement *thread;
gst_init (&amp;argc,&amp;argv);
if (argc != 2) {
g_print ("usage: %s &lt;filename&gt;\n", argv[0]);
exit (-1);
}
/* create a new thread to hold the elements */
thread = gst_thread_new ("thread");
g_assert (thread != NULL);
/* create a new bin to hold the elements */
bin = gst_bin_new ("bin");
g_assert (bin != NULL);
/* create a disk reader */
disksrc = gst_elementfactory_make ("disksrc", "disk_source");
g_assert (disksrc != NULL);
gtk_object_set (GTK_OBJECT (disksrc), "location", argv[1], NULL);
gtk_signal_connect (GTK_OBJECT (disksrc), "eos",
GTK_SIGNAL_FUNC (eos), thread);
queue = gst_elementfactory_make ("queue", "queue");
/* and an audio sink */
audiosink = gst_elementfactory_make ("audiosink", "play_audio");
g_assert (audiosink != NULL);
parse = gst_elementfactory_make ("mp3parse", "parse");
decode = gst_elementfactory_make ("mpg123", "decode");
/* add objects to the main bin */
gst_bin_add (GST_BIN (bin), disksrc);
gst_bin_add (GST_BIN (bin), queue);
gst_bin_add (GST_BIN (thread), parse);
gst_bin_add (GST_BIN (thread), decode);
gst_bin_add (GST_BIN (thread), audiosink);
gst_pad_connect (gst_element_get_pad (disksrc,"src"),
gst_element_get_pad (queue,"sink"));
gst_pad_connect (gst_element_get_pad (queue, "src"),
gst_element_get_pad (parse, "sink"));
gst_pad_connect (gst_element_get_pad (parse, "src"),
gst_element_get_pad (decode, "sink"));
gst_pad_connect (gst_element_get_pad (decode, "src"),
gst_element_get_pad (audiosink, "sink"));
gst_bin_add (GST_BIN (bin), thread);
/* make it ready */
gst_element_set_state (GST_ELEMENT (bin), GST_STATE_READY);
/* start playing */
gst_element_set_state (GST_ELEMENT (bin), GST_STATE_PLAYING);
playing = TRUE;
while (playing) {
gst_bin_iterate (GST_BIN (bin));
}
gst_element_set_state (GST_ELEMENT (bin), GST_STATE_NULL);
exit (0);
}
</programlisting>
</chapter>

32
docs/manual/quotes.sgml
View file

@ -44,6 +44,38 @@
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>5/6 Jan 2001</term>
<listitem>
<para>
<emphasis>wtay:</emphasis>
we need to cut down the time to create an mp3 player down to
seconds...
</para>
<para>
<emphasis>richardb:</emphasis>
:)
</para>
<para>
<emphasis>Omega:</emphasis>
I'm wanting to something more interesting soon, I did the "draw an mp3
player in 15sec" back in October '99.
</para>
<para>
<emphasis>wtay:</emphasis>
by the time Omega gets his hands on the editor, you'll see a
complete audio mixer in the editor :-)
</para>
<para>
<emphasis>richardb:</emphasis>
Well, it clearly has the potential...
</para>
<para>
<emphasis>Omega:</emphasis>
Working on it... ;-)
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>28 Dec 2000</term>
<listitem>

49
docs/manual/states.sgml
View file

@ -41,6 +41,55 @@
<graphic fileref="images/state-diagram" format="png"></graphic>
</figure>
</para>
<para>
The state of an element can be changed with the following code:
</para>
<programlisting>
GstElement *bin;
// create a bin, put elements in it and connect them
...
gst_element_set_state (bin, GST_STATE_PLAYING);
...
</programlisting>
<para>
You can set the following states to an element:
</para>
<informaltable pgwide=1 frame="none" role="enum">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row>
<entry><literal>GST_STATE_NONE_PENDING</literal></entry>
<entry>The element is in the desired state.
</entry>
</row>
<row>
<entry><literal>GST_STATE_NULL</literal></entry>
<entry>Reset the state of an element.
</entry>
</row>
<row>
<entry><literal>GST_STATE_READY</literal></entry>
<entry>will make the element ready to start processing data.
</entry>
</row>
<row>
<entry><literal>GST_STATE_PLAYING</literal></entry>
<entry>means there really is data flowing through the graph.
</entry>
</row>
<row>
<entry><literal>GST_STATE_PAUSED</literal></entry>
<entry>temporary stops the data flow.
</entry>
</row>
</tbody>
</tgroup>
</informaltable>
</sect1>
<sect1 id="sec-states-null">

174
docs/manual/xml.sgml
View file

@ -1,6 +1,178 @@
<chapter id="cha-xml">
<title>XML in GStreamer</title>
<title>XML in <application>GStreamer</application></title>
<para>
<application>GStreamer</application> uses XML to store and load
its pipeline definitions. XML is also used internally to manage the
plugin registry. The plugin registry is a file that contains the definition
of all the plugins <application>GStreamer</application> knows about to have
quick access to the specifics of the plugins.
</para>
<para>
We will show you how you can save a pipeline to XML and how you can reload that
XML file again for later use.
</para>
<sect1 id="sec-xml-write">
<title>Turning GstElements into XML</title>
<para>
We create a simple pipeline and save it to disk with gst_xml_write (). The following
code constructs an mp3 player pipeline with two threads and finaly writes it to disk.
use this program with one argument: the mp3 file on disk.
</para>
<programlisting>
#include &lt;stdlib.h&gt;
#include &lt;gst/gst.h&gt;
gboolean playing;
int
main (int argc, char *argv[])
{
GstElement *disksrc, *audiosink, *queue, *queue2, *parse, *decode;
GstElement *bin;
GstElement *thread, *thread2;
gst_init (&amp;argc,&amp;argv);
if (argc != 2) {
g_print ("usage: %s &lt;filename&gt;\n", argv[0]);
exit (-1);
}
/* create a new thread to hold the elements */
thread = gst_elementfactory_make ("thread", "thread");
g_assert (thread != NULL);
thread2 = gst_elementfactory_make ("thread", "thread2");
g_assert (thread2 != NULL);
/* create a new bin to hold the elements */
bin = gst_bin_new ("bin");
g_assert (bin != NULL);
/* create a disk reader */
disksrc = gst_elementfactory_make ("disksrc", "disk_source");
g_assert (disksrc != NULL);
gtk_object_set (GTK_OBJECT (disksrc), "location", argv[1], NULL);
queue = gst_elementfactory_make ("queue", "queue");
queue2 = gst_elementfactory_make ("queue", "queue2");
/* and an audio sink */
audiosink = gst_elementfactory_make ("audiosink", "play_audio");
g_assert (audiosink != NULL);
parse = gst_elementfactory_make ("mp3parse", "parse");
decode = gst_elementfactory_make ("mpg123", "decode");
/* add objects to the main bin */
gst_bin_add (GST_BIN (bin), disksrc);
gst_bin_add (GST_BIN (bin), queue);
gst_bin_add (GST_BIN (thread), parse);
gst_bin_add (GST_BIN (thread), decode);
gst_bin_add (GST_BIN (thread), queue2);
gst_bin_add (GST_BIN (thread2), audiosink);
gst_pad_connect (gst_element_get_pad (disksrc,"src"),
gst_element_get_pad (queue,"sink"));
gst_pad_connect (gst_element_get_pad (queue,"src"),
gst_element_get_pad (parse,"sink"));
gst_pad_connect (gst_element_get_pad (parse,"src"),
gst_element_get_pad (decode,"sink"));
gst_pad_connect (gst_element_get_pad (decode,"src"),
gst_element_get_pad (queue2,"sink"));
gst_pad_connect (gst_element_get_pad (queue2,"src"),
gst_element_get_pad (audiosink,"sink"));
gst_bin_add (GST_BIN (bin), thread);
gst_bin_add (GST_BIN (bin), thread2);
// write the bin to disk
xmlSaveFile ("xmlTest.gst", gst_xml_write (GST_ELEMENT (bin)));
exit (0);
}
</programlisting>
<para>
The most important line is:
</para>
<programlisting>
xmlSaveFile ("xmlTest.gst", gst_xml_write (GST_ELEMENT (bin)));
</programlisting>
<para>
gst_xml_write () will turn the given element into and xmlDocPtr that
can be saved with the xmlSaveFile () function found in the gnome-xml
package. The result is an XML file named xmlTest.gst.
</para>
<para>
The complete element hierarchy will be saved along with the inter element
pad connections and the element parameters. Future <application>GStreamer</application>
versions will also allow you to store the signals in the XML file.
</para>
</sect1>
<sect1 id="sec-xml-load">
<title>Loading a GstElement from an XML file</title>
<para>
A saved XML file can be loade with the gst_xml_new (filename, rootelement).
The root element can optionally left NULL. The following code example loads
the previously created XML file and runs it.
</para>
<programlisting>
#include &lt;stdlib.h&gt;
#include &lt;gst/gst.h&gt;
gboolean playing;
/* eos will be called when the src element has an end of stream */
void
eos (GstElement *element, gpointer data)
{
g_print ("have eos, quitting\n");
playing = FALSE;
}
int
main(int argc, char *argv[])
{
GstXML *xml;
GstElement *bin;
GstElement *disk;
gst_init (&amp;argc, &amp;argv);
xml = gst_xml_new ("xmlTest.gst", NULL);
bin = gst_xml_get_element (xml, "bin");
gst_element_set_state (bin, GST_STATE_PLAYING);
playing = TRUE;
while (playing) {
gst_bin_iterate (GST_BIN (bin));
}
gst_element_set_state (bin, GST_STATE_NULL);
exit (0);
}
</programlisting>
<para>
gst_xml_get_element (xml, "name") can be used to get a specific element
from the XML file.
</para>
<para>
gst_xml_get_topelements (xml) can be used to get a list of all toplevel elements
in the XML file.
</para>
</sect1>
</chapter>

2
docs/plugins/Makefile.am
View file

@ -15,7 +15,7 @@ LDADD = $(GLIB_LIBS) $(GTK_LIBS) $(top_srcdir)/gst/libgst.la
CFLAGS = `gstreamer-config --cflags` -Wall -g
LDFLAGS = `gstreamer-config --libs`
EXTRA_DIST=$(DOC_MODULE).types.in
EXTRA_DIST=$(DOC_MODULE).types.in $(DOC_MODULE)-sections.txt $(DOC_MAIN_SGML_FILE) gstdoc-mkdb gstdoc-mktmpl gstdoc-scanobj
HTML_DIR=$(datadir)/$(DOC_MODULE)/html

3
docs/plugins/gstdoc-scanobj
View file

@ -835,7 +835,8 @@ output_widget_pads (FILE *fp, GstElement *element)
GstPad *pad = (GstPad *)pads->data;
GstType *type;
type = gst_type_find_by_id(pad->type);
//type = gst_type_find_by_id(pad->type);
type = gst_type_find_by_id(1);
fprintf (fp, "<PAD>\n<NAME>%s::%s</NAME>\n",
gtk_type_name(factory->type), pad->name);

1
docs/random/testing/syntax
View file

@ -21,6 +21,7 @@ tcS: id1, element, signalname (attach to signal in an element)
tcS: id2, element, signalname
...
tcI: the number of iterations on the top bin
tcT: a timeout value in mSecs
tcR: id1,1,id2,1,.. (the pattern of signals trigered)
or
tcR: id1==id2,... (denote an equal number of signals)

1
examples/xml/runxml.c
View file

@ -23,7 +23,6 @@ int main(int argc,char *argv[])
bin = gst_xml_get_element(xml, "bin");
gst_element_set_state(bin, GST_STATE_READY);
gst_element_set_state(bin, GST_STATE_PLAYING);
playing = TRUE;

22
gst/gstxml.c
View file

@ -23,6 +23,7 @@
#include "gst_private.h"
#include "gstxml.h"
#include "gstbin.h"
static void gst_xml_class_init (GstXMLClass *klass);
@ -175,13 +176,30 @@ GstElement*
gst_xml_get_element (GstXML *xml, const guchar *name)
{
GstElement *element;
GList *topelements;
g_return_val_if_fail(xml != NULL, NULL);
g_return_val_if_fail(name != NULL, NULL);
GST_DEBUG (0,"gstxml: getting element \"%s\"\n", name);
element = g_hash_table_lookup(xml->elements, name);
topelements = gst_xml_get_topelements (xml);
return element;
while (topelements) {
GstElement *top = GST_ELEMENT (topelements->data);
if (!strcmp (gst_element_get_name (top), name)) {
return top;
}
else {
if (GST_IS_BIN (top)) {
element = gst_bin_get_by_name (GST_BIN (top), name);
if (element)
return element;
}
}
topelements = g_list_next (topelements);
}
return NULL;
}

1
tests/old/examples/xml/runxml.c
View file

@ -23,7 +23,6 @@ int main(int argc,char *argv[])
bin = gst_xml_get_element(xml, "bin");
gst_element_set_state(bin, GST_STATE_READY);
gst_element_set_state(bin, GST_STATE_PLAYING);
playing = TRUE;

2
tests/sched/testcases1.tc
View file

@ -3,6 +3,7 @@ tcP: fakesrc ! fakesink
tcS: A, fakesrc0, handoff
tcS: B, fakesink0, handoff
tcI: 2
tcT: 2000
tcR: A,1,B,1,A,1,B,1
@ -12,5 +13,6 @@ tcS: A, fakesrc0, handoff
tcS: B, identity, handoff
tcS: C, fakesink0, handoff
tcI: 2
tcT: 2000
tcR: A,1,B,1,C,1,A,1,B,1,C,1