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/*
* RTP Demux element
*
* Copyright (C) 2005 Nokia Corporation.
* @author Kai Vehmanen <kai.vehmanen@nokia.com>
*
* Loosely based on GStreamer gstdecodebin
* Copyright (C) <2004> Wim Taymans <wim.taymans@gmail.com>
*
* 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-gstrtpptdemux
* @short_description: separate RTP payloads based on the payload type
*
* <refsect2>
* <para>
* gstrtpptdemux acts as a demuxer for RTP packets based on the payload type of the
* packets. Its main purpose is to allow an application to easily receive and
* decode an RTP stream with multiple payload types.
* </para>
* <para>
* For each payload type that is detected, a new pad will be created and the
* ::new-payload-type signal will be emitted. When the payload for the RTP
* stream changes, the ::payload-type-change signal will be emitted.
* </para>
* <para>
* The element will try to set complete and unique application/x-rtp caps on the
* outgoing buffers and pads based on the result of the ::request-pt-map signal.
* </para>
* <title>Example pipelines</title>
* <para>
* <programlisting>
* gst-launch udpsrc caps="application/x-rtp" ! gstrtpptdemux ! fakesink
* </programlisting>
* Takes an RTP stream and send the RTP packets with the first detected payload
* type to fakesink, discarding the other payload types.
* </para>
* </refsect2>
*
* Last reviewed on 2007-05-28 (0.10.5)
*/
/*
* Contributors:
* Andre Moreira Magalhaes <andre.magalhaes@indt.org.br>
*/
/*
* Status:
* - works with the test_rtpdemux.c tool
*
* Check:
* - is emitting a signal enough, or should we
* use GstEvent to notify downstream elements
* of the new packet... no?
*
* Notes:
* - emits event both for new PTs, and whenever
* a PT is changed
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <gst/gst.h>
#include <gst/rtp/gstrtpbuffer.h>
#include "gstrtpbin-marshal.h"
#include "gstrtpptdemux.h"
/* generic templates */
static GstStaticPadTemplate rtp_pt_demux_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp")
);
static GstStaticPadTemplate rtp_pt_demux_src_template =
GST_STATIC_PAD_TEMPLATE ("src_%d",
GST_PAD_SRC,
GST_PAD_SOMETIMES,
GST_STATIC_CAPS ("application/x-rtp, " "payload = (int) [ 0, 255 ]")
);
GST_DEBUG_CATEGORY_STATIC (gst_rtp_pt_demux_debug);
#define GST_CAT_DEFAULT gst_rtp_pt_demux_debug
/**
* Item for storing GstPad<->pt pairs.
*/
struct _GstRtpPtDemuxPad
{
GstPad *pad; /**< pointer to the actual pad */
gint pt; /**< RTP payload-type attached to pad */
gboolean newcaps;
};
/* signals */
enum
{
SIGNAL_REQUEST_PT_MAP,
SIGNAL_NEW_PAYLOAD_TYPE,
SIGNAL_PAYLOAD_TYPE_CHANGE,
SIGNAL_CLEAR_PT_MAP,
LAST_SIGNAL
};
GST_BOILERPLATE (GstRtpPtDemux, gst_rtp_pt_demux, GstElement, GST_TYPE_ELEMENT);
static void gst_rtp_pt_demux_finalize (GObject * object);
static void gst_rtp_pt_demux_release (GstRtpPtDemux * ptdemux);
static gboolean gst_rtp_pt_demux_setup (GstRtpPtDemux * ptdemux);
static GstFlowReturn gst_rtp_pt_demux_chain (GstPad * pad, GstBuffer * buf);
static GstStateChangeReturn gst_rtp_pt_demux_change_state (GstElement * element,
GstStateChange transition);
static void gst_rtp_pt_demux_clear_pt_map (GstRtpPtDemux * rtpdemux);
static GstRtpPtDemuxPad *find_pad_for_pt (GstRtpPtDemux * rtpdemux, guint8 pt);
static guint gst_rtp_pt_demux_signals[LAST_SIGNAL] = { 0 };
static GstElementDetails gst_rtp_pt_demux_details = {
"RTP Demux",
"Demux/Network/RTP",
"Parses codec streams transmitted in the same RTP session",
"Kai Vehmanen <kai.vehmanen@nokia.com>"
};
static void
gst_rtp_pt_demux_base_init (gpointer g_class)
{
GstElementClass *gstelement_klass = GST_ELEMENT_CLASS (g_class);
gst_element_class_add_pad_template (gstelement_klass,
gst_static_pad_template_get (&rtp_pt_demux_sink_template));
gst_element_class_add_pad_template (gstelement_klass,
gst_static_pad_template_get (&rtp_pt_demux_src_template));
gst_element_class_set_details (gstelement_klass, &gst_rtp_pt_demux_details);
}
static void
gst_rtp_pt_demux_class_init (GstRtpPtDemuxClass * klass)
{
GObjectClass *gobject_klass;
GstElementClass *gstelement_klass;
gobject_klass = (GObjectClass *) klass;
gstelement_klass = (GstElementClass *) klass;
/**
* GstRtpPtDemux::request-pt-map:
* @demux: the object which received the signal
* @pt: the payload type
*
* Request the payload type as #GstCaps for @pt.
*/
gst_rtp_pt_demux_signals[SIGNAL_REQUEST_PT_MAP] =
g_signal_new ("request-pt-map", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRtpPtDemuxClass, request_pt_map),
NULL, NULL, gst_rtp_bin_marshal_BOXED__UINT, GST_TYPE_CAPS, 1,
G_TYPE_UINT);
/**
* GstRtpPtDemux::new-payload-type:
* @demux: the object which received the signal
* @pt: the payload type
* @pad: the pad with the new payload
*
* Emited when a new payload type pad has been created in @demux.
*/
gst_rtp_pt_demux_signals[SIGNAL_NEW_PAYLOAD_TYPE] =
g_signal_new ("new-payload-type", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRtpPtDemuxClass, new_payload_type),
NULL, NULL, gst_rtp_bin_marshal_VOID__UINT_OBJECT, G_TYPE_NONE, 2,
G_TYPE_UINT, GST_TYPE_PAD);
/**
* GstRtpPtDemux::payload-type-change:
* @demux: the object which received the signal
* @pt: the new payload type
*
* Emited when the payload type changed.
*/
gst_rtp_pt_demux_signals[SIGNAL_PAYLOAD_TYPE_CHANGE] =
g_signal_new ("payload-type-change", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRtpPtDemuxClass,
payload_type_change), NULL, NULL, g_cclosure_marshal_VOID__UINT,
G_TYPE_NONE, 1, G_TYPE_UINT);
/**
* GstRtpPtDemux::clear-pt-map:
* @demux: the object which received the signal
*
* The application can call this signal to instruct the element to discard the
* currently cached payload type map.
*/
gst_rtp_pt_demux_signals[SIGNAL_CLEAR_PT_MAP] =
g_signal_new ("clear-pt-map", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_ACTION | G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRtpPtDemuxClass,
clear_pt_map), NULL, NULL, g_cclosure_marshal_VOID__VOID,
G_TYPE_NONE, 0, G_TYPE_NONE);
gobject_klass->finalize = GST_DEBUG_FUNCPTR (gst_rtp_pt_demux_finalize);
gstelement_klass->change_state =
GST_DEBUG_FUNCPTR (gst_rtp_pt_demux_change_state);
klass->clear_pt_map = GST_DEBUG_FUNCPTR (gst_rtp_pt_demux_clear_pt_map);
GST_DEBUG_CATEGORY_INIT (gst_rtp_pt_demux_debug,
"rtpptdemux", 0, "RTP codec demuxer");
}
static void
gst_rtp_pt_demux_init (GstRtpPtDemux * ptdemux, GstRtpPtDemuxClass * g_class)
{
GstElementClass *klass = GST_ELEMENT_GET_CLASS (ptdemux);
ptdemux->sink =
gst_pad_new_from_template (gst_element_class_get_pad_template (klass,
"sink"), "sink");
g_assert (ptdemux->sink != NULL);
gst_pad_set_chain_function (ptdemux->sink, gst_rtp_pt_demux_chain);
gst_element_add_pad (GST_ELEMENT (ptdemux), ptdemux->sink);
}
static void
gst_rtp_pt_demux_finalize (GObject * object)
{
gst_rtp_pt_demux_release (GST_RTP_PT_DEMUX (object));
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static GstCaps *
gst_rtp_pt_demux_get_caps (GstRtpPtDemux * rtpdemux, guint pt)
{
GstCaps *caps;
GValue ret = { 0 };
GValue args[2] = { {0}, {0} };
/* figure out the caps */
g_value_init (&args[0], GST_TYPE_ELEMENT);
g_value_set_object (&args[0], rtpdemux);
g_value_init (&args[1], G_TYPE_UINT);
g_value_set_uint (&args[1], pt);
g_value_init (&ret, GST_TYPE_CAPS);
g_value_set_boxed (&ret, NULL);
g_signal_emitv (args, gst_rtp_pt_demux_signals[SIGNAL_REQUEST_PT_MAP], 0,
&ret);
g_value_unset (&args[0]);
g_value_unset (&args[1]);
caps = g_value_dup_boxed (&ret);
g_value_unset (&ret);
if (caps == NULL)
caps = GST_PAD_CAPS (rtpdemux->sink);
GST_DEBUG ("pt %d, got caps %" GST_PTR_FORMAT, pt, caps);
return caps;
}
static void
gst_rtp_pt_demux_clear_pt_map (GstRtpPtDemux * rtpdemux)
{
GSList *walk;
GST_OBJECT_LOCK (rtpdemux);
GST_DEBUG ("clearing pt map");
for (walk = rtpdemux->srcpads; walk; walk = g_slist_next (walk)) {
GstRtpPtDemuxPad *pad = walk->data;
pad->newcaps = TRUE;
}
GST_OBJECT_UNLOCK (rtpdemux);
}
static GstFlowReturn
gst_rtp_pt_demux_chain (GstPad * pad, GstBuffer * buf)
{
GstFlowReturn ret = GST_FLOW_OK;
GstRtpPtDemux *rtpdemux;
GstElement *element = GST_ELEMENT (GST_OBJECT_PARENT (pad));
guint8 pt;
GstPad *srcpad;
GstRtpPtDemuxPad *rtpdemuxpad;
GstCaps *caps;
rtpdemux = GST_RTP_PT_DEMUX (GST_OBJECT_PARENT (pad));
if (!gst_rtp_buffer_validate (buf))
goto invalid_buffer;
pt = gst_rtp_buffer_get_payload_type (buf);
GST_DEBUG_OBJECT (rtpdemux, "received buffer for pt %d", pt);
rtpdemuxpad = find_pad_for_pt (rtpdemux, pt);
if (rtpdemuxpad == NULL) {
/* new PT, create a src pad */
GstElementClass *klass;
GstPadTemplate *templ;
gchar *padname;
klass = GST_ELEMENT_GET_CLASS (rtpdemux);
templ = gst_element_class_get_pad_template (klass, "src_%d");
padname = g_strdup_printf ("src_%d", pt);
srcpad = gst_pad_new_from_template (templ, padname);
gst_pad_use_fixed_caps (srcpad);
g_free (padname);
caps = gst_rtp_pt_demux_get_caps (rtpdemux, pt);
if (!caps)
goto no_caps;
caps = gst_caps_make_writable (caps);
gst_caps_set_simple (caps, "payload", G_TYPE_INT, pt, NULL);
gst_pad_set_caps (srcpad, caps);
GST_DEBUG ("Adding pt=%d to the list.", pt);
rtpdemuxpad = g_new0 (GstRtpPtDemuxPad, 1);
rtpdemuxpad->pt = pt;
rtpdemuxpad->newcaps = FALSE;
rtpdemuxpad->pad = srcpad;
GST_OBJECT_LOCK (rtpdemux);
rtpdemux->srcpads = g_slist_append (rtpdemux->srcpads, rtpdemuxpad);
GST_OBJECT_UNLOCK (rtpdemux);
gst_pad_set_active (srcpad, TRUE);
gst_element_add_pad (element, srcpad);
GST_DEBUG ("emitting new-payload_type for pt %d", pt);
g_signal_emit (G_OBJECT (rtpdemux),
gst_rtp_pt_demux_signals[SIGNAL_NEW_PAYLOAD_TYPE], 0, pt, srcpad);
}
srcpad = rtpdemuxpad->pad;
if (pt != rtpdemux->last_pt) {
gint emit_pt = pt;
/* our own signal with an extra flag that this is the only pad */
rtpdemux->last_pt = pt;
GST_DEBUG ("emitting payload-type-changed for pt %d", emit_pt);
g_signal_emit (G_OBJECT (rtpdemux),
gst_rtp_pt_demux_signals[SIGNAL_PAYLOAD_TYPE_CHANGE], 0, emit_pt);
}
if (rtpdemuxpad->newcaps) {
GST_DEBUG ("need new caps");
caps = gst_rtp_pt_demux_get_caps (rtpdemux, pt);
if (!caps)
goto no_caps;
caps = gst_caps_make_writable (caps);
gst_caps_set_simple (caps, "payload", G_TYPE_INT, pt, NULL);
gst_pad_set_caps (srcpad, caps);
rtpdemuxpad->newcaps = FALSE;
}
gst_buffer_set_caps (buf, GST_PAD_CAPS (srcpad));
/* push to srcpad */
ret = gst_pad_push (srcpad, buf);
return ret;
/* ERRORS */
invalid_buffer:
{
/* this is fatal and should be filtered earlier */
GST_ELEMENT_ERROR (rtpdemux, STREAM, DECODE, (NULL),
("Dropping invalid RTP payload"));
gst_buffer_unref (buf);
return GST_FLOW_ERROR;
}
no_caps:
{
GST_ELEMENT_ERROR (rtpdemux, STREAM, DECODE, (NULL),
("Could not get caps for payload"));
gst_buffer_unref (buf);
return GST_FLOW_ERROR;
}
}
static GstRtpPtDemuxPad *
find_pad_for_pt (GstRtpPtDemux * rtpdemux, guint8 pt)
{
GstRtpPtDemuxPad *respad = NULL;
GSList *walk;
for (walk = rtpdemux->srcpads; walk; walk = g_slist_next (walk)) {
GstRtpPtDemuxPad *pad = walk->data;
if (pad->pt == pt) {
respad = pad;
break;
}
}
return respad;
}
/**
* Reserves resources for the object.
*/
static gboolean
gst_rtp_pt_demux_setup (GstRtpPtDemux * ptdemux)
{
ptdemux->srcpads = NULL;
ptdemux->last_pt = 0xFFFF;
return TRUE;
}
/**
* Free resources for the object.
*/
static void
gst_rtp_pt_demux_release (GstRtpPtDemux * ptdemux)
{
GSList *walk;
for (walk = ptdemux->srcpads; walk; walk = g_slist_next (walk)) {
GstRtpPtDemuxPad *pad = walk->data;
gst_pad_set_active (pad->pad, FALSE);
gst_element_remove_pad (GST_ELEMENT_CAST (ptdemux), pad->pad);
g_free (pad);
}
g_slist_free (ptdemux->srcpads);
ptdemux->srcpads = NULL;
}
static GstStateChangeReturn
gst_rtp_pt_demux_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret;
GstRtpPtDemux *ptdemux;
ptdemux = GST_RTP_PT_DEMUX (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
if (gst_rtp_pt_demux_setup (ptdemux) != TRUE)
ret = GST_STATE_CHANGE_FAILURE;
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
case GST_STATE_CHANGE_PAUSED_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_NULL:
gst_rtp_pt_demux_release (ptdemux);
break;
default:
break;
}
return ret;
}
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