gstreamer/subprojects/gst-plugins-good/gst/rtpmanager/gstrtprtxsend.c

1299 lines
41 KiB
C

/* RTP Retransmission sender element for GStreamer
*
* gstrtprtxsend.c:
*
* Copyright (C) 2013 Collabora Ltd.
* @author Julien Isorce <julien.isorce@collabora.co.uk>
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:element-rtprtxsend
* @title: rtprtxsend
*
* See #GstRtpRtxReceive for examples
*
* The purpose of the sender RTX object is to keep a history of RTP packets up
* to a configurable limit (max-size-time or max-size-packets). It will listen
* for upstream custom retransmission events (GstRTPRetransmissionRequest) that
* comes from downstream (#GstRtpSession). When receiving a request it will
* look up the requested seqnum in its list of stored packets. If the packet
* is available, it will create a RTX packet according to RFC 4588 and send
* this as an auxiliary stream. RTX is SSRC-multiplexed
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include <string.h>
#include <stdlib.h>
#include "gstrtprtxsend.h"
GST_DEBUG_CATEGORY_STATIC (gst_rtp_rtx_send_debug);
#define GST_CAT_DEFAULT gst_rtp_rtx_send_debug
#define DEFAULT_RTX_PAYLOAD_TYPE 0
#define DEFAULT_MAX_SIZE_TIME 0
#define DEFAULT_MAX_SIZE_PACKETS 100
enum
{
PROP_0,
PROP_SSRC_MAP,
PROP_PAYLOAD_TYPE_MAP,
PROP_MAX_SIZE_TIME,
PROP_MAX_SIZE_PACKETS,
PROP_NUM_RTX_REQUESTS,
PROP_NUM_RTX_PACKETS,
PROP_CLOCK_RATE_MAP,
};
enum
{
SIGNAL_0,
SIGNAL_ADD_EXTENSION,
SIGNAL_CLEAR_EXTENSIONS,
LAST_SIGNAL
};
static guint gst_rtp_rtx_send_signals[LAST_SIGNAL] = { 0, };
#define RTPHDREXT_BUNDLE_MID GST_RTP_HDREXT_BASE "sdes:mid"
#define RTPHDREXT_STREAM_ID GST_RTP_HDREXT_BASE "sdes:rtp-stream-id"
#define RTPHDREXT_REPAIRED_STREAM_ID GST_RTP_HDREXT_BASE "sdes:repaired-rtp-stream-id"
static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp")
);
static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp")
);
static gboolean gst_rtp_rtx_send_queue_check_full (GstDataQueue * queue,
guint visible, guint bytes, guint64 time, gpointer checkdata);
static gboolean gst_rtp_rtx_send_src_event (GstPad * pad, GstObject * parent,
GstEvent * event);
static gboolean gst_rtp_rtx_send_sink_event (GstPad * pad, GstObject * parent,
GstEvent * event);
static GstFlowReturn gst_rtp_rtx_send_chain (GstPad * pad, GstObject * parent,
GstBuffer * buffer);
static GstFlowReturn gst_rtp_rtx_send_chain_list (GstPad * pad,
GstObject * parent, GstBufferList * list);
static void gst_rtp_rtx_send_src_loop (GstRtpRtxSend * rtx);
static gboolean gst_rtp_rtx_send_activate_mode (GstPad * pad,
GstObject * parent, GstPadMode mode, gboolean active);
static GstStateChangeReturn gst_rtp_rtx_send_change_state (GstElement *
element, GstStateChange transition);
static void gst_rtp_rtx_send_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_rtp_rtx_send_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_rtp_rtx_send_finalize (GObject * object);
static void
gst_rtp_rtx_send_add_extension (GstRtpRtxSend * rtx,
GstRTPHeaderExtension * ext)
{
g_return_if_fail (GST_IS_RTP_HEADER_EXTENSION (ext));
g_return_if_fail (gst_rtp_header_extension_get_id (ext) > 0);
GST_OBJECT_LOCK (rtx);
if (g_strcmp0 (gst_rtp_header_extension_get_uri (ext),
RTPHDREXT_STREAM_ID) == 0) {
gst_clear_object (&rtx->rid_stream);
rtx->rid_stream = gst_object_ref (ext);
} else if (g_strcmp0 (gst_rtp_header_extension_get_uri (ext),
RTPHDREXT_REPAIRED_STREAM_ID) == 0) {
gst_clear_object (&rtx->rid_repaired);
rtx->rid_repaired = gst_object_ref (ext);
} else {
g_warning ("rtprtxsend (%s) doesn't know how to deal with the "
"RTP Header Extension with URI \'%s\'", GST_OBJECT_NAME (rtx),
gst_rtp_header_extension_get_uri (ext));
}
/* XXX: check for other duplicate ids? */
GST_OBJECT_UNLOCK (rtx);
}
static void
gst_rtp_rtx_send_clear_extensions (GstRtpRtxSend * rtx)
{
GST_OBJECT_LOCK (rtx);
gst_clear_object (&rtx->rid_stream);
gst_clear_object (&rtx->rid_repaired);
GST_OBJECT_UNLOCK (rtx);
}
G_DEFINE_TYPE_WITH_CODE (GstRtpRtxSend, gst_rtp_rtx_send, GST_TYPE_ELEMENT,
GST_DEBUG_CATEGORY_INIT (gst_rtp_rtx_send_debug, "rtprtxsend", 0,
"rtp retransmission sender"));
GST_ELEMENT_REGISTER_DEFINE (rtprtxsend, "rtprtxsend", GST_RANK_NONE,
GST_TYPE_RTP_RTX_SEND);
#define IS_RTX_ENABLED(rtx) (g_hash_table_size ((rtx)->rtx_pt_map) > 0)
typedef struct
{
guint16 seqnum;
guint32 timestamp;
GstBuffer *buffer;
} BufferQueueItem;
static void
buffer_queue_item_free (BufferQueueItem * item)
{
gst_buffer_unref (item->buffer);
g_free (item);
}
typedef struct
{
guint32 rtx_ssrc;
guint16 seqnum_base, next_seqnum;
gint clock_rate;
/* history of rtp packets */
GSequence *queue;
} SSRCRtxData;
static SSRCRtxData *
ssrc_rtx_data_new (guint32 rtx_ssrc)
{
SSRCRtxData *data = g_new0 (SSRCRtxData, 1);
data->rtx_ssrc = rtx_ssrc;
data->next_seqnum = data->seqnum_base = g_random_int_range (0, G_MAXUINT16);
data->queue = g_sequence_new ((GDestroyNotify) buffer_queue_item_free);
return data;
}
static void
ssrc_rtx_data_free (SSRCRtxData * data)
{
g_sequence_free (data->queue);
g_free (data);
}
typedef enum
{
RTX_TASK_START,
RTX_TASK_PAUSE,
RTX_TASK_STOP,
} RtxTaskState;
static void
gst_rtp_rtx_send_set_flushing (GstRtpRtxSend * rtx, gboolean flush)
{
GST_OBJECT_LOCK (rtx);
gst_data_queue_set_flushing (rtx->queue, flush);
gst_data_queue_flush (rtx->queue);
GST_OBJECT_UNLOCK (rtx);
}
static gboolean
gst_rtp_rtx_send_set_task_state (GstRtpRtxSend * rtx, RtxTaskState task_state)
{
GstTask *task = GST_PAD_TASK (rtx->srcpad);
GstPadMode mode = GST_PAD_MODE (rtx->srcpad);
gboolean ret = TRUE;
switch (task_state) {
case RTX_TASK_START:
{
gboolean active = task && GST_TASK_STATE (task) == GST_TASK_STARTED;
if (IS_RTX_ENABLED (rtx) && mode != GST_PAD_MODE_NONE && !active) {
GST_DEBUG_OBJECT (rtx, "Starting RTX task");
gst_rtp_rtx_send_set_flushing (rtx, FALSE);
ret = gst_pad_start_task (rtx->srcpad,
(GstTaskFunction) gst_rtp_rtx_send_src_loop, rtx, NULL);
}
break;
}
case RTX_TASK_PAUSE:
if (task) {
GST_DEBUG_OBJECT (rtx, "Pausing RTX task");
gst_rtp_rtx_send_set_flushing (rtx, TRUE);
ret = gst_pad_pause_task (rtx->srcpad);
}
break;
case RTX_TASK_STOP:
if (task) {
GST_DEBUG_OBJECT (rtx, "Stopping RTX task");
gst_rtp_rtx_send_set_flushing (rtx, TRUE);
ret = gst_pad_stop_task (rtx->srcpad);
}
break;
}
return ret;
}
static void
gst_rtp_rtx_send_class_init (GstRtpRtxSendClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
gobject_class->get_property = gst_rtp_rtx_send_get_property;
gobject_class->set_property = gst_rtp_rtx_send_set_property;
gobject_class->finalize = gst_rtp_rtx_send_finalize;
g_object_class_install_property (gobject_class, PROP_SSRC_MAP,
g_param_spec_boxed ("ssrc-map", "SSRC Map",
"Map of SSRCs to their retransmission SSRCs for SSRC-multiplexed mode"
" (default = random)", GST_TYPE_STRUCTURE,
G_PARAM_WRITABLE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_PAYLOAD_TYPE_MAP,
g_param_spec_boxed ("payload-type-map", "Payload Type Map",
"Map of original payload types to their retransmission payload types",
GST_TYPE_STRUCTURE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_MAX_SIZE_TIME,
g_param_spec_uint ("max-size-time", "Max Size Time",
"Amount of ms to queue (0 = unlimited)", 0, G_MAXUINT,
DEFAULT_MAX_SIZE_TIME, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_MAX_SIZE_PACKETS,
g_param_spec_uint ("max-size-packets", "Max Size Packets",
"Amount of packets to queue (0 = unlimited)", 0, G_MAXINT16,
DEFAULT_MAX_SIZE_PACKETS,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_NUM_RTX_REQUESTS,
g_param_spec_uint ("num-rtx-requests", "Num RTX Requests",
"Number of retransmission events received", 0, G_MAXUINT,
0, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_NUM_RTX_PACKETS,
g_param_spec_uint ("num-rtx-packets", "Num RTX Packets",
" Number of retransmission packets sent", 0, G_MAXUINT,
0, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_CLOCK_RATE_MAP,
g_param_spec_boxed ("clock-rate-map", "Clock Rate Map",
"Map of payload types to their clock rates",
GST_TYPE_STRUCTURE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
/**
* rtprtxsend::add-extension:
*
* Add @ext as an extension for writing part of an RTP header extension onto
* outgoing RTP packets. Currently only supports using the following
* extension URIs. All other RTP header extensions are copied as-is.
* - "urn:ietf:params:rtp-hdrext:sdes:rtp-stream-id": will be removed
* - "urn:ietf:params:rtp-hdrext:sdes:repaired-rtp-stream-id": will be
* written instead of the "rtp-stream-id" header extension.
*
* Since: 1.22
*/
gst_rtp_rtx_send_signals[SIGNAL_ADD_EXTENSION] =
g_signal_new_class_handler ("add-extension", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,
G_CALLBACK (gst_rtp_rtx_send_add_extension), NULL, NULL, NULL,
G_TYPE_NONE, 1, GST_TYPE_RTP_HEADER_EXTENSION);
/**
* rtprtxsend::clear-extensions:
* @object: the #GstRTPBasePayload
*
* Clear all RTP header extensions used by this rtprtxsend.
*
* Since: 1.22
*/
gst_rtp_rtx_send_signals[SIGNAL_CLEAR_EXTENSIONS] =
g_signal_new_class_handler ("clear-extensions", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,
G_CALLBACK (gst_rtp_rtx_send_clear_extensions), NULL, NULL, NULL,
G_TYPE_NONE, 0);
gst_element_class_add_static_pad_template (gstelement_class, &src_factory);
gst_element_class_add_static_pad_template (gstelement_class, &sink_factory);
gst_element_class_set_static_metadata (gstelement_class,
"RTP Retransmission Sender", "Codec",
"Retransmit RTP packets when needed, according to RFC4588",
"Julien Isorce <julien.isorce@collabora.co.uk>");
gstelement_class->change_state =
GST_DEBUG_FUNCPTR (gst_rtp_rtx_send_change_state);
}
static void
gst_rtp_rtx_send_reset (GstRtpRtxSend * rtx)
{
GST_OBJECT_LOCK (rtx);
gst_data_queue_flush (rtx->queue);
g_hash_table_remove_all (rtx->ssrc_data);
g_hash_table_remove_all (rtx->rtx_ssrcs);
rtx->num_rtx_requests = 0;
rtx->num_rtx_packets = 0;
GST_OBJECT_UNLOCK (rtx);
}
static void
gst_rtp_rtx_send_finalize (GObject * object)
{
GstRtpRtxSend *rtx = GST_RTP_RTX_SEND_CAST (object);
g_hash_table_unref (rtx->ssrc_data);
g_hash_table_unref (rtx->rtx_ssrcs);
if (rtx->external_ssrc_map)
gst_structure_free (rtx->external_ssrc_map);
g_hash_table_unref (rtx->rtx_pt_map);
if (rtx->rtx_pt_map_structure)
gst_structure_free (rtx->rtx_pt_map_structure);
g_hash_table_unref (rtx->clock_rate_map);
if (rtx->clock_rate_map_structure)
gst_structure_free (rtx->clock_rate_map_structure);
g_object_unref (rtx->queue);
gst_clear_object (&rtx->rid_stream);
gst_clear_object (&rtx->rid_repaired);
gst_clear_buffer (&rtx->dummy_writable);
G_OBJECT_CLASS (gst_rtp_rtx_send_parent_class)->finalize (object);
}
static void
gst_rtp_rtx_send_init (GstRtpRtxSend * rtx)
{
GstElementClass *klass = GST_ELEMENT_GET_CLASS (rtx);
rtx->srcpad =
gst_pad_new_from_template (gst_element_class_get_pad_template (klass,
"src"), "src");
GST_PAD_SET_PROXY_CAPS (rtx->srcpad);
GST_PAD_SET_PROXY_ALLOCATION (rtx->srcpad);
gst_pad_set_event_function (rtx->srcpad,
GST_DEBUG_FUNCPTR (gst_rtp_rtx_send_src_event));
gst_pad_set_activatemode_function (rtx->srcpad,
GST_DEBUG_FUNCPTR (gst_rtp_rtx_send_activate_mode));
gst_element_add_pad (GST_ELEMENT (rtx), rtx->srcpad);
rtx->sinkpad =
gst_pad_new_from_template (gst_element_class_get_pad_template (klass,
"sink"), "sink");
GST_PAD_SET_PROXY_CAPS (rtx->sinkpad);
GST_PAD_SET_PROXY_ALLOCATION (rtx->sinkpad);
gst_pad_set_event_function (rtx->sinkpad,
GST_DEBUG_FUNCPTR (gst_rtp_rtx_send_sink_event));
gst_pad_set_chain_function (rtx->sinkpad,
GST_DEBUG_FUNCPTR (gst_rtp_rtx_send_chain));
gst_pad_set_chain_list_function (rtx->sinkpad,
GST_DEBUG_FUNCPTR (gst_rtp_rtx_send_chain_list));
gst_element_add_pad (GST_ELEMENT (rtx), rtx->sinkpad);
rtx->queue = gst_data_queue_new (gst_rtp_rtx_send_queue_check_full, NULL,
NULL, rtx);
rtx->ssrc_data = g_hash_table_new_full (g_direct_hash, g_direct_equal,
NULL, (GDestroyNotify) ssrc_rtx_data_free);
rtx->rtx_ssrcs = g_hash_table_new (g_direct_hash, g_direct_equal);
rtx->rtx_pt_map = g_hash_table_new (g_direct_hash, g_direct_equal);
rtx->clock_rate_map = g_hash_table_new (g_direct_hash, g_direct_equal);
rtx->max_size_time = DEFAULT_MAX_SIZE_TIME;
rtx->max_size_packets = DEFAULT_MAX_SIZE_PACKETS;
rtx->dummy_writable = gst_buffer_new ();
}
static gboolean
gst_rtp_rtx_send_queue_check_full (GstDataQueue * queue,
guint visible, guint bytes, guint64 time, gpointer checkdata)
{
return FALSE;
}
static void
gst_rtp_rtx_data_queue_item_free (gpointer item)
{
GstDataQueueItem *data = item;
if (data->object)
gst_mini_object_unref (data->object);
g_free (data);
}
static gboolean
gst_rtp_rtx_send_push_out (GstRtpRtxSend * rtx, gpointer object)
{
GstDataQueueItem *data;
gboolean success;
data = g_new0 (GstDataQueueItem, 1);
data->object = GST_MINI_OBJECT (object);
data->size = 1;
data->duration = 1;
data->visible = TRUE;
data->destroy = gst_rtp_rtx_data_queue_item_free;
success = gst_data_queue_push (rtx->queue, data);
if (!success)
data->destroy (data);
return success;
}
static guint32
gst_rtp_rtx_send_choose_ssrc (GstRtpRtxSend * rtx, guint32 choice,
gboolean consider_choice)
{
guint32 ssrc = consider_choice ? choice : g_random_int ();
/* make sure to be different than any other */
while (g_hash_table_contains (rtx->ssrc_data, GUINT_TO_POINTER (ssrc)) ||
g_hash_table_contains (rtx->rtx_ssrcs, GUINT_TO_POINTER (ssrc))) {
ssrc = g_random_int ();
}
return ssrc;
}
static SSRCRtxData *
gst_rtp_rtx_send_get_ssrc_data (GstRtpRtxSend * rtx, guint32 ssrc)
{
SSRCRtxData *data;
guint32 rtx_ssrc = 0;
gboolean consider = FALSE;
if (G_UNLIKELY (!g_hash_table_contains (rtx->ssrc_data,
GUINT_TO_POINTER (ssrc)))) {
if (rtx->external_ssrc_map) {
gchar *ssrc_str;
ssrc_str = g_strdup_printf ("%" G_GUINT32_FORMAT, ssrc);
consider = gst_structure_get_uint (rtx->external_ssrc_map, ssrc_str,
&rtx_ssrc);
g_free (ssrc_str);
}
rtx_ssrc = gst_rtp_rtx_send_choose_ssrc (rtx, rtx_ssrc, consider);
data = ssrc_rtx_data_new (rtx_ssrc);
g_hash_table_insert (rtx->ssrc_data, GUINT_TO_POINTER (ssrc), data);
g_hash_table_insert (rtx->rtx_ssrcs, GUINT_TO_POINTER (rtx_ssrc),
GUINT_TO_POINTER (ssrc));
} else {
data = g_hash_table_lookup (rtx->ssrc_data, GUINT_TO_POINTER (ssrc));
}
return data;
}
static GstMemory *
rewrite_header_extensions (GstRtpRtxSend * rtx, GstRTPBuffer * rtp)
{
gsize out_size = rtp->size[1] + 32;
guint16 bit_pattern;
guint8 *pdata;
guint wordlen;
GstMemory *mem;
GstMapInfo map;
mem = gst_allocator_alloc (NULL, out_size, NULL);
gst_memory_map (mem, &map, GST_MAP_READWRITE);
if (gst_rtp_buffer_get_extension_data (rtp, &bit_pattern, (gpointer) & pdata,
&wordlen)) {
GstRTPHeaderExtensionFlags ext_flags = 0;
gsize bytelen = wordlen * 4;
guint hdr_unit_bytes;
gsize read_offset = 0, write_offset = 4;
if (bit_pattern == 0xBEDE) {
/* one byte extensions */
hdr_unit_bytes = 1;
ext_flags |= GST_RTP_HEADER_EXTENSION_ONE_BYTE;
} else if (bit_pattern >> 4 == 0x100) {
/* two byte extensions */
hdr_unit_bytes = 2;
ext_flags |= GST_RTP_HEADER_EXTENSION_TWO_BYTE;
} else {
GST_DEBUG_OBJECT (rtx, "unknown extension bit pattern 0x%02x%02x",
bit_pattern >> 8, bit_pattern & 0xff);
goto copy_as_is;
}
GST_WRITE_UINT16_BE (map.data, bit_pattern);
while (TRUE) {
guint8 read_id, read_len;
if (read_offset + hdr_unit_bytes >= bytelen)
/* not enough remaning data */
break;
if (ext_flags & GST_RTP_HEADER_EXTENSION_ONE_BYTE) {
read_id = GST_READ_UINT8 (pdata + read_offset) >> 4;
read_len = (GST_READ_UINT8 (pdata + read_offset) & 0x0F) + 1;
read_offset += 1;
if (read_id == 0)
/* padding */
continue;
if (read_id == 15)
/* special id for possible future expansion */
break;
} else {
read_id = GST_READ_UINT8 (pdata + read_offset);
read_offset += 1;
if (read_id == 0)
/* padding */
continue;
read_len = GST_READ_UINT8 (pdata + read_offset);
read_offset += 1;
}
GST_TRACE_OBJECT (rtx, "found rtp header extension with id %u and "
"length %u", read_id, read_len);
/* Ignore extension headers where the size does not fit */
if (read_offset + read_len > bytelen) {
GST_WARNING_OBJECT (rtx, "Extension length extends past the "
"size of the extension data");
break;
}
/* rewrite the rtp-stream-id into a repaired-stream-id */
if (rtx->rid_stream
&& read_id == gst_rtp_header_extension_get_id (rtx->rid_stream)) {
if (!gst_rtp_header_extension_read (rtx->rid_stream, ext_flags,
&pdata[read_offset], read_len, rtx->dummy_writable)) {
GST_WARNING_OBJECT (rtx, "RTP header extension (%s) could "
"not read payloaded data", GST_OBJECT_NAME (rtx->rid_stream));
goto copy_as_is;
}
if (rtx->rid_repaired) {
guint8 write_id = gst_rtp_header_extension_get_id (rtx->rid_repaired);
gsize written;
char *rid;
g_object_get (rtx->rid_stream, "rid", &rid, NULL);
g_object_set (rtx->rid_repaired, "rid", rid, NULL);
g_clear_pointer (&rid, g_free);
written =
gst_rtp_header_extension_write (rtx->rid_repaired, rtp->buffer,
ext_flags, rtx->dummy_writable,
&map.data[write_offset + hdr_unit_bytes],
map.size - write_offset - hdr_unit_bytes);
GST_TRACE_OBJECT (rtx->rid_repaired, "wrote %" G_GSIZE_FORMAT,
written);
if (written <= 0) {
GST_WARNING_OBJECT (rtx, "Failed to rewrite RID for RTX");
goto copy_as_is;
} else {
if (ext_flags & GST_RTP_HEADER_EXTENSION_ONE_BYTE) {
map.data[write_offset] =
((write_id & 0x0F) << 4) | ((written - 1) & 0x0F);
} else if (ext_flags & GST_RTP_HEADER_EXTENSION_TWO_BYTE) {
map.data[write_offset] = write_id & 0xFF;
map.data[write_offset + 1] = written & 0xFF;
} else {
g_assert_not_reached ();
goto copy_as_is;
}
write_offset += written + hdr_unit_bytes;
}
}
} else {
/* TODO: may need to write mid at different times to the original
* buffer to account for the difference in timing of acknowledgement
* of the rtx ssrc from the original ssrc. This may add extra data to
* the header extension space that needs to be accounted for.
*/
memcpy (&map.data[write_offset], &pdata[read_offset - hdr_unit_bytes],
read_len + hdr_unit_bytes);
write_offset += read_len + hdr_unit_bytes;
}
read_offset += read_len;
}
/* subtract the ext header */
wordlen = write_offset / 4 + ((write_offset % 4) ? 1 : 0);
/* wordlen in the ext data doesn't include the 4-byte header */
GST_WRITE_UINT16_BE (map.data + 2, wordlen - 1);
if (wordlen * 4 > write_offset)
memset (&map.data[write_offset], 0, wordlen * 4 - write_offset);
GST_MEMDUMP_OBJECT (rtx, "generated ext data", map.data, wordlen * 4);
} else {
copy_as_is:
wordlen = rtp->size[1] / 4;
memcpy (map.data, rtp->data[1], rtp->size[1]);
GST_LOG_OBJECT (rtx, "copying data as-is");
}
gst_memory_unmap (mem, &map);
gst_memory_resize (mem, 0, wordlen * 4);
return mem;
}
/* Copy fixed header and extension. Add OSN before to copy payload
* Copy memory to avoid to manually copy each rtp buffer field.
*/
static GstBuffer *
gst_rtp_rtx_buffer_new (GstRtpRtxSend * rtx, GstBuffer * buffer)
{
GstMemory *mem = NULL;
GstRTPBuffer rtp = GST_RTP_BUFFER_INIT;
GstRTPBuffer new_rtp = GST_RTP_BUFFER_INIT;
GstBuffer *new_buffer = gst_buffer_new ();
GstMapInfo map;
guint payload_len = 0;
SSRCRtxData *data;
guint32 ssrc;
guint16 seqnum;
guint8 fmtp;
gst_rtp_buffer_map (buffer, GST_MAP_READ, &rtp);
/* get needed data from GstRtpRtxSend */
ssrc = gst_rtp_buffer_get_ssrc (&rtp);
data = gst_rtp_rtx_send_get_ssrc_data (rtx, ssrc);
ssrc = data->rtx_ssrc;
seqnum = data->next_seqnum++;
fmtp = GPOINTER_TO_UINT (g_hash_table_lookup (rtx->rtx_pt_map,
GUINT_TO_POINTER (gst_rtp_buffer_get_payload_type (&rtp))));
GST_DEBUG_OBJECT (rtx, "creating rtx buffer, orig seqnum: %u, "
"rtx seqnum: %u, rtx ssrc: %X", gst_rtp_buffer_get_seq (&rtp),
seqnum, ssrc);
/* gst_rtp_buffer_map does not map the payload so do it now */
gst_rtp_buffer_get_payload (&rtp);
/* copy fixed header */
mem = gst_memory_copy (rtp.map[0].memory, 0, rtp.size[0]);
gst_buffer_append_memory (new_buffer, mem);
/* copy extension if any */
if (rtp.size[1]) {
mem = rewrite_header_extensions (rtx, &rtp);
gst_buffer_append_memory (new_buffer, mem);
}
/* copy payload and add OSN just before */
payload_len = 2 + rtp.size[2];
mem = gst_allocator_alloc (NULL, payload_len, NULL);
gst_memory_map (mem, &map, GST_MAP_WRITE);
GST_WRITE_UINT16_BE (map.data, gst_rtp_buffer_get_seq (&rtp));
if (rtp.size[2])
memcpy (map.data + 2, rtp.data[2], rtp.size[2]);
gst_memory_unmap (mem, &map);
gst_buffer_append_memory (new_buffer, mem);
/* everything needed is copied */
gst_rtp_buffer_unmap (&rtp);
/* set ssrc, seqnum and fmtp */
gst_rtp_buffer_map (new_buffer, GST_MAP_WRITE, &new_rtp);
gst_rtp_buffer_set_ssrc (&new_rtp, ssrc);
gst_rtp_buffer_set_seq (&new_rtp, seqnum);
gst_rtp_buffer_set_payload_type (&new_rtp, fmtp);
/* RFC 4588: let other elements do the padding, as normal */
gst_rtp_buffer_set_padding (&new_rtp, FALSE);
gst_rtp_buffer_unmap (&new_rtp);
/* Copy over timestamps */
gst_buffer_copy_into (new_buffer, buffer, GST_BUFFER_COPY_TIMESTAMPS, 0, -1);
/* mark this is a RETRANSMISSION buffer */
GST_BUFFER_FLAG_SET (new_buffer, GST_RTP_BUFFER_FLAG_RETRANSMISSION);
return new_buffer;
}
static gint
buffer_queue_items_cmp (BufferQueueItem * a, BufferQueueItem * b,
gpointer user_data)
{
/* gst_rtp_buffer_compare_seqnum returns the opposite of what we want,
* it returns negative when seqnum1 > seqnum2 and we want negative
* when b > a, i.e. a is smaller, so it comes first in the sequence */
return gst_rtp_buffer_compare_seqnum (b->seqnum, a->seqnum);
}
static gboolean
gst_rtp_rtx_send_src_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstRtpRtxSend *rtx = GST_RTP_RTX_SEND_CAST (parent);
gboolean res;
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_CUSTOM_UPSTREAM:
{
const GstStructure *s = gst_event_get_structure (event);
/* This event usually comes from the downstream gstrtpsession */
if (gst_structure_has_name (s, "GstRTPRetransmissionRequest")) {
guint seqnum = 0;
guint ssrc = 0;
GstBuffer *rtx_buf = NULL;
/* retrieve seqnum of the packet that need to be retransmitted */
if (!gst_structure_get_uint (s, "seqnum", &seqnum))
seqnum = -1;
/* retrieve ssrc of the packet that need to be retransmitted */
if (!gst_structure_get_uint (s, "ssrc", &ssrc))
ssrc = -1;
GST_DEBUG_OBJECT (rtx, "got rtx request for seqnum: %u, ssrc: %X",
seqnum, ssrc);
GST_OBJECT_LOCK (rtx);
/* check if request is for us */
if (g_hash_table_contains (rtx->ssrc_data, GUINT_TO_POINTER (ssrc))) {
SSRCRtxData *data;
GSequenceIter *iter;
BufferQueueItem search_item;
/* update statistics */
++rtx->num_rtx_requests;
data = gst_rtp_rtx_send_get_ssrc_data (rtx, ssrc);
search_item.seqnum = seqnum;
iter = g_sequence_lookup (data->queue, &search_item,
(GCompareDataFunc) buffer_queue_items_cmp, NULL);
if (iter) {
BufferQueueItem *item = g_sequence_get (iter);
GST_LOG_OBJECT (rtx, "found %u", item->seqnum);
rtx_buf = gst_rtp_rtx_buffer_new (rtx, item->buffer);
}
#ifndef GST_DISABLE_DEBUG
else {
BufferQueueItem *item = NULL;
iter = g_sequence_get_begin_iter (data->queue);
if (!g_sequence_iter_is_end (iter))
item = g_sequence_get (iter);
if (item && seqnum < item->seqnum) {
GST_DEBUG_OBJECT (rtx, "requested seqnum %u has already been "
"removed from the rtx queue; the first available is %u",
seqnum, item->seqnum);
} else {
GST_WARNING_OBJECT (rtx, "requested seqnum %u has not been "
"transmitted yet in the original stream; either the remote end "
"is not configured correctly, or the source is too slow",
seqnum);
}
}
#endif
}
GST_OBJECT_UNLOCK (rtx);
if (rtx_buf)
gst_rtp_rtx_send_push_out (rtx, rtx_buf);
gst_event_unref (event);
res = TRUE;
/* This event usually comes from the downstream gstrtpsession */
} else if (gst_structure_has_name (s, "GstRTPCollision")) {
guint ssrc = 0;
if (!gst_structure_get_uint (s, "ssrc", &ssrc))
ssrc = -1;
GST_DEBUG_OBJECT (rtx, "got ssrc collision, ssrc: %X", ssrc);
GST_OBJECT_LOCK (rtx);
/* choose another ssrc for our retransmitted stream */
if (g_hash_table_contains (rtx->rtx_ssrcs, GUINT_TO_POINTER (ssrc))) {
guint master_ssrc;
SSRCRtxData *data;
master_ssrc = GPOINTER_TO_UINT (g_hash_table_lookup (rtx->rtx_ssrcs,
GUINT_TO_POINTER (ssrc)));
data = gst_rtp_rtx_send_get_ssrc_data (rtx, master_ssrc);
/* change rtx_ssrc and update the reverse map */
data->rtx_ssrc = gst_rtp_rtx_send_choose_ssrc (rtx, 0, FALSE);
g_hash_table_remove (rtx->rtx_ssrcs, GUINT_TO_POINTER (ssrc));
g_hash_table_insert (rtx->rtx_ssrcs,
GUINT_TO_POINTER (data->rtx_ssrc),
GUINT_TO_POINTER (master_ssrc));
GST_OBJECT_UNLOCK (rtx);
/* no need to forward to payloader because we make sure to have
* a different ssrc
*/
gst_event_unref (event);
res = TRUE;
} else {
/* if master ssrc has collided, remove it from our data, as it
* is not going to be used any longer */
if (g_hash_table_contains (rtx->ssrc_data, GUINT_TO_POINTER (ssrc))) {
SSRCRtxData *data;
data = gst_rtp_rtx_send_get_ssrc_data (rtx, ssrc);
g_hash_table_remove (rtx->rtx_ssrcs,
GUINT_TO_POINTER (data->rtx_ssrc));
g_hash_table_remove (rtx->ssrc_data, GUINT_TO_POINTER (ssrc));
}
GST_OBJECT_UNLOCK (rtx);
/* forward event to payloader in case collided ssrc is
* master stream */
res = gst_pad_event_default (pad, parent, event);
}
} else {
res = gst_pad_event_default (pad, parent, event);
}
break;
}
default:
res = gst_pad_event_default (pad, parent, event);
break;
}
return res;
}
static gboolean
gst_rtp_rtx_send_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstRtpRtxSend *rtx = GST_RTP_RTX_SEND_CAST (parent);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_FLUSH_START:
gst_pad_push_event (rtx->srcpad, event);
gst_rtp_rtx_send_set_task_state (rtx, RTX_TASK_PAUSE);
return TRUE;
case GST_EVENT_FLUSH_STOP:
gst_pad_push_event (rtx->srcpad, event);
gst_rtp_rtx_send_set_task_state (rtx, RTX_TASK_START);
return TRUE;
case GST_EVENT_EOS:
GST_INFO_OBJECT (rtx, "Got EOS - enqueueing it");
gst_rtp_rtx_send_push_out (rtx, event);
return TRUE;
case GST_EVENT_CAPS:
{
GstCaps *caps;
GstStructure *s;
guint ssrc;
gint payload;
gpointer rtx_payload;
SSRCRtxData *data;
gst_event_parse_caps (event, &caps);
s = gst_caps_get_structure (caps, 0);
if (!gst_structure_get_uint (s, "ssrc", &ssrc))
ssrc = -1;
if (!gst_structure_get_int (s, "payload", &payload))
payload = -1;
if (payload == -1 || ssrc == G_MAXUINT)
break;
if (payload == -1)
GST_WARNING_OBJECT (rtx, "No payload in caps");
GST_OBJECT_LOCK (rtx);
data = gst_rtp_rtx_send_get_ssrc_data (rtx, ssrc);
if (!g_hash_table_lookup_extended (rtx->rtx_pt_map,
GUINT_TO_POINTER (payload), NULL, &rtx_payload))
rtx_payload = GINT_TO_POINTER (-1);
if (rtx->rtx_pt_map_structure && GPOINTER_TO_INT (rtx_payload) == -1
&& payload != -1)
GST_WARNING_OBJECT (rtx, "Payload %d not in rtx-pt-map", payload);
GST_DEBUG_OBJECT (rtx,
"got caps for payload: %d->%d, ssrc: %u->%u : %" GST_PTR_FORMAT,
payload, GPOINTER_TO_INT (rtx_payload), ssrc, data->rtx_ssrc, caps);
gst_structure_get_int (s, "clock-rate", &data->clock_rate);
caps = gst_caps_copy (caps);
/* The session might need to know the RTX ssrc */
if (GPOINTER_TO_INT (rtx_payload) != -1) {
gst_caps_set_simple (caps, "rtx-ssrc", G_TYPE_UINT, data->rtx_ssrc,
"rtx-seqnum-offset", G_TYPE_UINT, data->seqnum_base, NULL);
gst_caps_set_simple (caps, "rtx-payload", G_TYPE_INT,
GPOINTER_TO_INT (rtx_payload), NULL);
}
GST_DEBUG_OBJECT (rtx, "got clock-rate from caps: %d for ssrc: %u",
data->clock_rate, ssrc);
GST_OBJECT_UNLOCK (rtx);
gst_event_unref (event);
event = gst_event_new_caps (caps);
gst_caps_unref (caps);
break;
}
default:
break;
}
return gst_pad_event_default (pad, parent, event);
}
/* like rtp_jitter_buffer_get_ts_diff() */
static guint32
gst_rtp_rtx_send_get_ts_diff (SSRCRtxData * data)
{
guint64 high_ts, low_ts;
BufferQueueItem *high_buf, *low_buf;
guint32 result;
high_buf =
g_sequence_get (g_sequence_iter_prev (g_sequence_get_end_iter
(data->queue)));
low_buf = g_sequence_get (g_sequence_get_begin_iter (data->queue));
if (!high_buf || !low_buf || high_buf == low_buf)
return 0;
if (data->clock_rate) {
high_ts = high_buf->timestamp;
low_ts = low_buf->timestamp;
/* it needs to work if ts wraps */
if (high_ts >= low_ts) {
result = (guint32) (high_ts - low_ts);
} else {
result = (guint32) (high_ts + G_MAXUINT32 + 1 - low_ts);
}
result = gst_util_uint64_scale_int (result, 1000, data->clock_rate);
} else {
high_ts = GST_BUFFER_PTS (high_buf->buffer);
low_ts = GST_BUFFER_PTS (low_buf->buffer);
result = gst_util_uint64_scale_int_round (high_ts - low_ts, 1, GST_MSECOND);
}
return result;
}
/* Must be called with lock */
static void
process_buffer (GstRtpRtxSend * rtx, GstBuffer * buffer)
{
GstRTPBuffer rtp = GST_RTP_BUFFER_INIT;
BufferQueueItem *item;
SSRCRtxData *data;
guint16 seqnum;
guint8 payload_type;
guint32 ssrc, rtptime;
/* read the information we want from the buffer */
gst_rtp_buffer_map (buffer, GST_MAP_READ, &rtp);
seqnum = gst_rtp_buffer_get_seq (&rtp);
payload_type = gst_rtp_buffer_get_payload_type (&rtp);
ssrc = gst_rtp_buffer_get_ssrc (&rtp);
rtptime = gst_rtp_buffer_get_timestamp (&rtp);
gst_rtp_buffer_unmap (&rtp);
GST_TRACE_OBJECT (rtx, "Processing buffer seqnum: %u, ssrc: %X", seqnum,
ssrc);
/* do not store the buffer if it's payload type is unknown */
if (g_hash_table_contains (rtx->rtx_pt_map, GUINT_TO_POINTER (payload_type))) {
data = gst_rtp_rtx_send_get_ssrc_data (rtx, ssrc);
if (data->clock_rate == 0 && rtx->clock_rate_map_structure) {
data->clock_rate =
GPOINTER_TO_INT (g_hash_table_lookup (rtx->clock_rate_map,
GUINT_TO_POINTER (payload_type)));
}
/* add current rtp buffer to queue history */
item = g_new0 (BufferQueueItem, 1);
item->seqnum = seqnum;
item->timestamp = rtptime;
item->buffer = gst_buffer_ref (buffer);
g_sequence_append (data->queue, item);
/* remove oldest packets from history if they are too many */
if (rtx->max_size_packets) {
while (g_sequence_get_length (data->queue) > rtx->max_size_packets)
g_sequence_remove (g_sequence_get_begin_iter (data->queue));
}
if (rtx->max_size_time) {
while (gst_rtp_rtx_send_get_ts_diff (data) > rtx->max_size_time)
g_sequence_remove (g_sequence_get_begin_iter (data->queue));
}
}
}
static GstFlowReturn
gst_rtp_rtx_send_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer)
{
GstRtpRtxSend *rtx = GST_RTP_RTX_SEND_CAST (parent);
GstFlowReturn ret;
GST_OBJECT_LOCK (rtx);
if (rtx->rtx_pt_map_structure)
process_buffer (rtx, buffer);
GST_OBJECT_UNLOCK (rtx);
ret = gst_pad_push (rtx->srcpad, buffer);
return ret;
}
static gboolean
process_buffer_from_list (GstBuffer ** buffer, guint idx, gpointer user_data)
{
process_buffer (user_data, *buffer);
return TRUE;
}
static GstFlowReturn
gst_rtp_rtx_send_chain_list (GstPad * pad, GstObject * parent,
GstBufferList * list)
{
GstRtpRtxSend *rtx = GST_RTP_RTX_SEND_CAST (parent);
GstFlowReturn ret;
GST_OBJECT_LOCK (rtx);
gst_buffer_list_foreach (list, process_buffer_from_list, rtx);
GST_OBJECT_UNLOCK (rtx);
ret = gst_pad_push_list (rtx->srcpad, list);
return ret;
}
static void
gst_rtp_rtx_send_src_loop (GstRtpRtxSend * rtx)
{
GstDataQueueItem *data;
if (gst_data_queue_pop (rtx->queue, &data)) {
GST_LOG_OBJECT (rtx, "pushing rtx buffer %p", data->object);
if (G_LIKELY (GST_IS_BUFFER (data->object))) {
GST_OBJECT_LOCK (rtx);
/* Update statistics just before pushing. */
rtx->num_rtx_packets++;
GST_OBJECT_UNLOCK (rtx);
gst_pad_push (rtx->srcpad, GST_BUFFER (data->object));
} else if (GST_IS_EVENT (data->object)) {
gst_pad_push_event (rtx->srcpad, GST_EVENT (data->object));
/* after EOS, we should not send any more buffers,
* even if there are more requests coming in */
if (GST_EVENT_TYPE (data->object) == GST_EVENT_EOS) {
gst_rtp_rtx_send_set_flushing (rtx, TRUE);
}
} else {
g_assert_not_reached ();
}
data->object = NULL; /* we no longer own that object */
data->destroy (data);
} else {
GST_LOG_OBJECT (rtx, "flushing");
gst_rtp_rtx_send_set_task_state (rtx, RTX_TASK_PAUSE);
}
}
static gboolean
gst_rtp_rtx_send_activate_mode (GstPad * pad, GstObject * parent,
GstPadMode mode, gboolean active)
{
GstRtpRtxSend *rtx = GST_RTP_RTX_SEND_CAST (parent);
gboolean ret = FALSE;
switch (mode) {
case GST_PAD_MODE_PUSH:
if (active) {
ret = gst_rtp_rtx_send_set_task_state (rtx, RTX_TASK_START);
} else {
ret = gst_rtp_rtx_send_set_task_state (rtx, RTX_TASK_STOP);
}
GST_INFO_OBJECT (rtx, "activate_mode: active %d, ret %d", active, ret);
break;
default:
break;
}
return ret;
}
static void
gst_rtp_rtx_send_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec)
{
GstRtpRtxSend *rtx = GST_RTP_RTX_SEND_CAST (object);
switch (prop_id) {
case PROP_PAYLOAD_TYPE_MAP:
GST_OBJECT_LOCK (rtx);
g_value_set_boxed (value, rtx->rtx_pt_map_structure);
GST_OBJECT_UNLOCK (rtx);
break;
case PROP_MAX_SIZE_TIME:
GST_OBJECT_LOCK (rtx);
g_value_set_uint (value, rtx->max_size_time);
GST_OBJECT_UNLOCK (rtx);
break;
case PROP_MAX_SIZE_PACKETS:
GST_OBJECT_LOCK (rtx);
g_value_set_uint (value, rtx->max_size_packets);
GST_OBJECT_UNLOCK (rtx);
break;
case PROP_NUM_RTX_REQUESTS:
GST_OBJECT_LOCK (rtx);
g_value_set_uint (value, rtx->num_rtx_requests);
GST_OBJECT_UNLOCK (rtx);
break;
case PROP_NUM_RTX_PACKETS:
GST_OBJECT_LOCK (rtx);
g_value_set_uint (value, rtx->num_rtx_packets);
GST_OBJECT_UNLOCK (rtx);
break;
case PROP_CLOCK_RATE_MAP:
GST_OBJECT_LOCK (rtx);
g_value_set_boxed (value, rtx->clock_rate_map_structure);
GST_OBJECT_UNLOCK (rtx);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static gboolean
structure_to_hash_table (GQuark field_id, const GValue * value, gpointer hash)
{
const gchar *field_str;
guint field_uint;
guint value_uint;
field_str = g_quark_to_string (field_id);
field_uint = atoi (field_str);
value_uint = g_value_get_uint (value);
g_hash_table_insert ((GHashTable *) hash, GUINT_TO_POINTER (field_uint),
GUINT_TO_POINTER (value_uint));
return TRUE;
}
static void
gst_rtp_rtx_send_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec)
{
GstRtpRtxSend *rtx = GST_RTP_RTX_SEND_CAST (object);
switch (prop_id) {
case PROP_SSRC_MAP:
GST_OBJECT_LOCK (rtx);
if (rtx->external_ssrc_map)
gst_structure_free (rtx->external_ssrc_map);
rtx->external_ssrc_map = g_value_dup_boxed (value);
GST_OBJECT_UNLOCK (rtx);
break;
case PROP_PAYLOAD_TYPE_MAP:
GST_OBJECT_LOCK (rtx);
if (rtx->rtx_pt_map_structure)
gst_structure_free (rtx->rtx_pt_map_structure);
rtx->rtx_pt_map_structure = g_value_dup_boxed (value);
g_hash_table_remove_all (rtx->rtx_pt_map);
gst_structure_foreach (rtx->rtx_pt_map_structure, structure_to_hash_table,
rtx->rtx_pt_map);
GST_OBJECT_UNLOCK (rtx);
if (IS_RTX_ENABLED (rtx))
gst_rtp_rtx_send_set_task_state (rtx, RTX_TASK_START);
else
gst_rtp_rtx_send_set_task_state (rtx, RTX_TASK_STOP);
break;
case PROP_MAX_SIZE_TIME:
GST_OBJECT_LOCK (rtx);
rtx->max_size_time = g_value_get_uint (value);
GST_OBJECT_UNLOCK (rtx);
break;
case PROP_MAX_SIZE_PACKETS:
GST_OBJECT_LOCK (rtx);
rtx->max_size_packets = g_value_get_uint (value);
GST_OBJECT_UNLOCK (rtx);
break;
case PROP_CLOCK_RATE_MAP:
GST_OBJECT_LOCK (rtx);
if (rtx->clock_rate_map_structure)
gst_structure_free (rtx->clock_rate_map_structure);
rtx->clock_rate_map_structure = g_value_dup_boxed (value);
g_hash_table_remove_all (rtx->clock_rate_map);
gst_structure_foreach (rtx->clock_rate_map_structure,
structure_to_hash_table, rtx->clock_rate_map);
GST_OBJECT_UNLOCK (rtx);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static GstStateChangeReturn
gst_rtp_rtx_send_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret;
GstRtpRtxSend *rtx;
rtx = GST_RTP_RTX_SEND_CAST (element);
switch (transition) {
default:
break;
}
ret =
GST_ELEMENT_CLASS (gst_rtp_rtx_send_parent_class)->change_state (element,
transition);
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_rtp_rtx_send_reset (rtx);
break;
default:
break;
}
return ret;
}