gstreamer/gst/autodetect/gstautovideosink.c
Thomas Vander Stichele 695afd0edf documenting auto*sink using strstr for the video sink lookup, class field is not ordered update other plugins
Original commit message from CVS:

* docs/plugins/Makefile.am:
* docs/plugins/gst-plugins-good-plugins-docs.sgml:
* docs/plugins/gst-plugins-good-plugins-sections.txt:
* gst/autodetect/gstautoaudiosink.c:
(gst_auto_audio_sink_base_init):
* gst/autodetect/gstautovideosink.c:
(gst_auto_video_sink_base_init),
(gst_auto_video_sink_factory_filter):
documenting auto*sink
using strstr for the video sink lookup, class field is not ordered

update other plugins
2005-11-25 21:02:16 +00:00

257 lines
7.2 KiB
C

/* GStreamer
* (c) 2005 Ronald S. Bultje <rbultje@ronald.bitfreak.net>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-autovideosink
* @see_also: autoaudiosink, ximagesink, xvimagesink, sdlvideosink
*
* <refsect2>
* <para>
* autovideosink is a video sink that automatically detects an appropriate
* video sink to use. It does so by scanning the registry for all elements
* that have <quote>Sink</quote> and <quote>Audio</quote> in the class field
* of their element information, and also have a non-zero autoplugging rank.
* </para>
* <title>Example launch line</title>
* <para>
* <programlisting>
* gst-launch -v -m videotestsrc ! autovideosink
* </programlisting>
* </para>
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "gstautovideosink.h"
#include "gstautodetect.h"
static GstStateChangeReturn
gst_auto_video_sink_change_state (GstElement * element,
GstStateChange transition);
GST_BOILERPLATE (GstAutoVideoSink, gst_auto_video_sink, GstBin, GST_TYPE_BIN);
static void
gst_auto_video_sink_base_init (gpointer klass)
{
GstElementClass *eklass = GST_ELEMENT_CLASS (klass);
GstElementDetails gst_auto_video_sink_details = {
"Auto video sink",
"Sink/Video",
"Wrapper video sink for automatically detected video sink",
"Ronald Bultje <rbultje@ronald.bitfreak.net>"
};
GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
gst_element_class_add_pad_template (eklass,
gst_static_pad_template_get (&sink_template));
gst_element_class_set_details (eklass, &gst_auto_video_sink_details);
}
static void
gst_auto_video_sink_class_init (GstAutoVideoSinkClass * klass)
{
GstElementClass *eklass = GST_ELEMENT_CLASS (klass);
eklass->change_state = GST_DEBUG_FUNCPTR (gst_auto_video_sink_change_state);
}
/*
* Hack to make initial linking work; ideally, this'd work even when
* no target has been assigned to the ghostpad yet.
*/
static void
gst_auto_video_sink_reset (GstAutoVideoSink * sink)
{
GstPad *targetpad;
/* fakesink placeholder */
if (sink->kid) {
gst_element_set_state (sink->kid, GST_STATE_NULL);
gst_bin_remove (GST_BIN (sink), sink->kid);
}
sink->kid = gst_element_factory_make ("fakesink", "tempsink");
gst_bin_add (GST_BIN (sink), sink->kid);
/* pad */
targetpad = gst_element_get_pad (sink->kid, "sink");
gst_ghost_pad_set_target (GST_GHOST_PAD (sink->pad), targetpad);
gst_object_unref (targetpad);
}
static void
gst_auto_video_sink_init (GstAutoVideoSink * sink,
GstAutoVideoSinkClass * g_class)
{
sink->pad = gst_ghost_pad_new_no_target ("sink", GST_PAD_SINK);
gst_element_add_pad (GST_ELEMENT (sink), sink->pad);
gst_auto_video_sink_reset (sink);
GST_OBJECT_FLAG_SET (sink, GST_ELEMENT_IS_SINK);
}
static gboolean
gst_auto_video_sink_factory_filter (GstPluginFeature * feature, gpointer data)
{
guint rank;
const gchar *klass;
/* we only care about element factories */
if (!GST_IS_ELEMENT_FACTORY (feature))
return FALSE;
/* video sinks */
klass = gst_element_factory_get_klass (GST_ELEMENT_FACTORY (feature));
if (!(strstr (klass, "Sink") && strstr (klass, "Video")))
return FALSE;
/* only select elements with autoplugging rank */
rank = gst_plugin_feature_get_rank (feature);
if (rank < GST_RANK_MARGINAL)
return FALSE;
return TRUE;
}
static gint
gst_auto_video_sink_compare_ranks (GstPluginFeature * f1, GstPluginFeature * f2)
{
gint diff;
diff = gst_plugin_feature_get_rank (f2) - gst_plugin_feature_get_rank (f1);
if (diff != 0)
return diff;
return strcmp (gst_plugin_feature_get_name (f2),
gst_plugin_feature_get_name (f1));
}
static GstElement *
gst_auto_video_sink_find_best (GstAutoVideoSink * sink)
{
GstElement *choice = NULL;
GList *list, *walk;
list = gst_registry_feature_filter (gst_registry_get_default (),
(GstPluginFeatureFilter) gst_auto_video_sink_factory_filter, FALSE, sink);
list = g_list_sort (list, (GCompareFunc) gst_auto_video_sink_compare_ranks);
for (walk = list; walk != NULL; walk = walk->next) {
GstElementFactory *f = GST_ELEMENT_FACTORY (walk->data);
GstElement *el;
GST_DEBUG_OBJECT (sink, "Trying %s", GST_PLUGIN_FEATURE (f)->name);
if ((el = gst_element_factory_create (f, "actual-sink"))) {
GstStateChangeReturn ret;
GST_DEBUG_OBJECT (sink, "Changing state to READY");
ret = gst_element_set_state (el, GST_STATE_READY);
if (ret == GST_STATE_CHANGE_SUCCESS) {
GST_DEBUG_OBJECT (sink, "success");
choice = el;
goto done;
}
GST_WARNING_OBJECT (sink, "Couldn't set READY: %d", ret);
ret = gst_element_set_state (el, GST_STATE_NULL);
if (ret != GST_STATE_CHANGE_SUCCESS)
GST_WARNING_OBJECT (sink,
"Couldn't set element to NULL prior to disposal.");
gst_object_unref (el);
}
}
done:
gst_plugin_feature_list_free (list);
return choice;
}
static gboolean
gst_auto_video_sink_detect (GstAutoVideoSink * sink)
{
GstElement *esink;
GstPad *targetpad;
if (sink->kid) {
gst_element_set_state (sink->kid, GST_STATE_NULL);
gst_bin_remove (GST_BIN (sink), sink->kid);
sink->kid = NULL;
}
/* find element */
GST_DEBUG_OBJECT (sink, "Creating new kid");
if (!(esink = gst_auto_video_sink_find_best (sink))) {
GST_ELEMENT_ERROR (sink, LIBRARY, INIT, (NULL),
("Failed to find a supported video sink"));
return FALSE;
}
sink->kid = esink;
gst_bin_add (GST_BIN (sink), esink);
/* attach ghost pad */
GST_DEBUG_OBJECT (sink, "Re-assigning ghostpad");
targetpad = gst_element_get_pad (sink->kid, "sink");
gst_ghost_pad_set_target (GST_GHOST_PAD (sink->pad), targetpad);
gst_object_unref (targetpad);
GST_DEBUG_OBJECT (sink, "done changing auto video sink");
return TRUE;
}
static GstStateChangeReturn
gst_auto_video_sink_change_state (GstElement * element,
GstStateChange transition)
{
GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
GstAutoVideoSink *sink = GST_AUTO_VIDEO_SINK (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
if (!gst_auto_video_sink_detect (sink))
return GST_STATE_CHANGE_FAILURE;
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_NULL:
gst_auto_video_sink_reset (sink);
break;
default:
break;
}
return ret;
}