gst-template gstreamer插件模板

/* * GStreamer * Copyright (C) 2005 Thomas Vander Stichele <thomas@apestaart.org> * Copyright (C) 2005 Ronald S. Bultje <rbultje@ronald.bitfreak.net> * Copyright (C) YEAR AUTHOR_NAME AUTHOR_EMAIL * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. * * Alternatively, the contents of this file may be used under the * GNU Lesser General Public License Version 2.1 (the "LGPL"), in * which case the following provisions apply instead of the ones * mentioned above: * * 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-plugin * * FIXME:Describe plugin here. * * <refsect2> * <title>Example launch line</title> * |[ * gst-launch -v -m fakesrc ! plugin ! fakesink silent=TRUE * ]| * </refsect2> */ #ifdef HAVE_CONFIG_H # include <config.h> #endif #include <gst/gst.h> #include "gstplugin.h" GST_DEBUG_CATEGORY_STATIC (gst_plugin_template_debug); #define GST_CAT_DEFAULT gst_plugin_template_debug /* Filter signals and args */ enum { /* FILL ME */ LAST_SIGNAL }; enum { PROP_0, PROP_SILENT }; /* the capabilities of the inputs and outputs. * * describe the real formats here. */ static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("ANY") ); static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("ANY") ); GST_BOILERPLATE (GstPluginTemplate, gst_plugin_template, GstElement, GST_TYPE_ELEMENT); static void gst_plugin_template_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_plugin_template_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static gboolean gst_plugin_template_set_caps (GstPad * pad, GstCaps * caps); static GstFlowReturn gst_plugin_template_chain (GstPad * pad, GstBuffer * buf); /* GObject vmethod implementations */ static void gst_plugin_template_base_init (gpointer gclass) { GstElementClass *element_class = GST_ELEMENT_CLASS (gclass); gst_element_class_set_details_simple(element_class, "Plugin", "FIXME:Generic", "FIXME:Generic Template Element", "AUTHOR_NAME AUTHOR_EMAIL"); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&src_factory)); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&sink_factory)); } /* initialize the plugin's class */ static void gst_plugin_template_class_init (GstPluginTemplateClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; gobject_class = (GObjectClass *) klass; gstelement_class = (GstElementClass *) klass; gobject_class->set_property = gst_plugin_template_set_property; gobject_class->get_property = gst_plugin_template_get_property; g_object_class_install_property (gobject_class, PROP_SILENT, g_param_spec_boolean ("silent", "Silent", "Produce verbose output ?", FALSE, G_PARAM_READWRITE)); } /* initialize the new element * instantiate pads and add them to element * set pad calback functions * initialize instance structure */ static void gst_plugin_template_init (GstPluginTemplate * filter, GstPluginTemplateClass * gclass) { filter->sinkpad = gst_pad_new_from_static_template (&sink_factory, "sink"); gst_pad_set_setcaps_function (filter->sinkpad, GST_DEBUG_FUNCPTR(gst_plugin_template_set_caps)); gst_pad_set_getcaps_function (filter->sinkpad, GST_DEBUG_FUNCPTR(gst_pad_proxy_getcaps)); gst_pad_set_chain_function (filter->sinkpad, GST_DEBUG_FUNCPTR(gst_plugin_template_chain)); filter->srcpad = gst_pad_new_from_static_template (&src_factory, "src"); gst_pad_set_getcaps_function (filter->srcpad, GST_DEBUG_FUNCPTR(gst_pad_proxy_getcaps)); gst_element_add_pad (GST_ELEMENT (filter), filter->sinkpad); gst_element_add_pad (GST_ELEMENT (filter), filter->srcpad); filter->silent = FALSE; } static void gst_plugin_template_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstPluginTemplate *filter = GST_PLUGIN_TEMPLATE (object); switch (prop_id) { case PROP_SILENT: filter->silent = g_value_get_boolean (value); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_plugin_template_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstPluginTemplate *filter = GST_PLUGIN_TEMPLATE (object); switch (prop_id) { case PROP_SILENT: g_value_set_boolean (value, filter->silent); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } /* GstElement vmethod implementations */ /* this function handles the link with other elements */ static gboolean gst_plugin_template_set_caps (GstPad * pad, GstCaps * caps) { GstPluginTemplate *filter; GstPad *otherpad; filter = GST_PLUGIN_TEMPLATE (gst_pad_get_parent (pad)); otherpad = (pad == filter->srcpad) ? filter->sinkpad : filter->srcpad; gst_object_unref (filter); return gst_pad_set_caps (otherpad, caps); } /* chain function * this function does the actual processing */ static GstFlowReturn gst_plugin_template_chain (GstPad * pad, GstBuffer * buf) { GstPluginTemplate *filter; filter = GST_PLUGIN_TEMPLATE (GST_OBJECT_PARENT (pad)); if (filter->silent == FALSE) g_print ("I'm plugged, therefore I'm in.\n"); /* just push out the incoming buffer without touching it */ return gst_pad_push (filter->srcpad, buf); } /* entry point to initialize the plug-in * initialize the plug-in itself * register the element factories and other features */ static gboolean plugin_init (GstPlugin * plugin) { /* debug category for fltering log messages * * exchange the string 'Template plugin' with your description */ GST_DEBUG_CATEGORY_INIT (gst_plugin_template_debug, "plugin", 0, "Template plugin"); return gst_element_register (plugin, "plugin", GST_RANK_NONE, GST_TYPE_PLUGIN_TEMPLATE); } /* gstreamer looks for th