gstreamer/subprojects/gst-plugins-bad/gst/gdp/gstgdppay.c

713 lines
21 KiB
C

/* GStreamer
* Copyright (C) 2006 Thomas Vander Stichele <thomas at apestaart dot org>
* Copyright (C) 2014 Tim-Philipp Müller <tim centricular 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:element-gdppay
* @title: gdppay
* @see_also: gdpdepay
*
* This element payloads GStreamer buffers and events using the
* GStreamer Data Protocol.
*
* |[
* gst-launch-1.0 -v -m videotestsrc num-buffers=50 ! gdppay ! filesink location=test.gdp
* ]| This pipeline creates a serialized video stream that can be played back
* with the example shown in gdpdepay.
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "dataprotocol.h"
#include "gstgdpelements.h"
#include "gstgdppay.h"
static GstStaticPadTemplate gdp_pay_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
static GstStaticPadTemplate gdp_pay_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-gdp"));
GST_DEBUG_CATEGORY_STATIC (gst_gdp_pay_debug);
#define GST_CAT_DEFAULT gst_gdp_pay_debug
#define DEFAULT_CRC_HEADER TRUE
#define DEFAULT_CRC_PAYLOAD FALSE
enum
{
PROP_0,
PROP_CRC_HEADER,
PROP_CRC_PAYLOAD
};
#define _do_init \
GST_DEBUG_CATEGORY_INIT (gst_gdp_pay_debug, "gdppay", 0, \
"GDP payloader");
#define gst_gdp_pay_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstGDPPay, gst_gdp_pay, GST_TYPE_ELEMENT, _do_init);
GST_ELEMENT_REGISTER_DEFINE_WITH_CODE (gdppay, "gdppay", GST_RANK_NONE,
GST_TYPE_GDP_PAY, gdp_element_init (plugin));
static void gst_gdp_pay_reset (GstGDPPay * this);
static GstFlowReturn gst_gdp_pay_chain (GstPad * pad, GstObject * parent,
GstBuffer * buffer);
static gboolean gst_gdp_pay_src_event (GstPad * pad, GstObject * parent,
GstEvent * event);
static gboolean gst_gdp_pay_sink_event (GstPad * pad, GstObject * parent,
GstEvent * event);
static GstStateChangeReturn gst_gdp_pay_change_state (GstElement *
element, GstStateChange transition);
static void gst_gdp_pay_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_gdp_pay_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_gdp_pay_finalize (GObject * gobject);
static void
gst_gdp_pay_class_init (GstGDPPayClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
gobject_class->set_property = gst_gdp_pay_set_property;
gobject_class->get_property = gst_gdp_pay_get_property;
gobject_class->finalize = gst_gdp_pay_finalize;
g_object_class_install_property (gobject_class, PROP_CRC_HEADER,
g_param_spec_boolean ("crc-header", "CRC Header",
"Calculate and store a CRC checksum on the header",
DEFAULT_CRC_HEADER, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_CRC_PAYLOAD,
g_param_spec_boolean ("crc-payload", "CRC Payload",
"Calculate and store a CRC checksum on the payload",
DEFAULT_CRC_PAYLOAD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gst_element_class_set_static_metadata (gstelement_class,
"GDP Payloader", "GDP/Payloader",
"Payloads GStreamer Data Protocol buffers",
"Thomas Vander Stichele <thomas at apestaart dot org>");
gst_element_class_add_static_pad_template (gstelement_class,
&gdp_pay_sink_template);
gst_element_class_add_static_pad_template (gstelement_class,
&gdp_pay_src_template);
gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_gdp_pay_change_state);
}
static void
gst_gdp_pay_init (GstGDPPay * gdppay)
{
gdppay->sinkpad =
gst_pad_new_from_static_template (&gdp_pay_sink_template, "sink");
gst_pad_set_chain_function (gdppay->sinkpad,
GST_DEBUG_FUNCPTR (gst_gdp_pay_chain));
gst_pad_set_event_function (gdppay->sinkpad,
GST_DEBUG_FUNCPTR (gst_gdp_pay_sink_event));
gst_element_add_pad (GST_ELEMENT (gdppay), gdppay->sinkpad);
gdppay->srcpad =
gst_pad_new_from_static_template (&gdp_pay_src_template, "src");
gst_pad_set_event_function (gdppay->srcpad,
GST_DEBUG_FUNCPTR (gst_gdp_pay_src_event));
gst_element_add_pad (GST_ELEMENT (gdppay), gdppay->srcpad);
gdppay->crc_header = DEFAULT_CRC_HEADER;
gdppay->crc_payload = DEFAULT_CRC_PAYLOAD;
gdppay->header_flag = gdppay->crc_header | gdppay->crc_payload;
gdppay->offset = 0;
}
static void
gst_gdp_pay_finalize (GObject * gobject)
{
GstGDPPay *this = GST_GDP_PAY (gobject);
gst_gdp_pay_reset (this);
GST_CALL_PARENT (G_OBJECT_CLASS, finalize, (gobject));
}
static void
gst_gdp_pay_reset (GstGDPPay * this)
{
GST_DEBUG_OBJECT (this, "Resetting GDP object");
/* clear the queued buffers */
while (this->queue) {
GstBuffer *buffer;
buffer = GST_BUFFER_CAST (this->queue->data);
/* delete buffer from queue now */
this->queue = g_list_delete_link (this->queue, this->queue);
gst_buffer_unref (buffer);
}
if (this->caps) {
gst_caps_unref (this->caps);
this->caps = NULL;
}
this->have_caps = FALSE;
this->have_segment = FALSE;
this->have_streamstartid = FALSE;
this->sent_streamheader = FALSE;
this->reset_streamheader = FALSE;
this->offset = 0;
}
/* set OFFSET and OFFSET_END with running count */
static void
gst_gdp_stamp_buffer (GstGDPPay * this, GstBuffer * buffer)
{
GST_BUFFER_OFFSET (buffer) = this->offset;
GST_BUFFER_OFFSET_END (buffer) = this->offset + gst_buffer_get_size (buffer);
this->offset = GST_BUFFER_OFFSET_END (buffer);
}
static GstBuffer *
gst_gdp_buffer_from_caps (GstGDPPay * this, GstCaps * caps)
{
return gst_dp_payload_caps (caps, this->header_flag);
}
static GstBuffer *
gst_gdp_pay_buffer_from_buffer (GstGDPPay * this, GstBuffer * buffer)
{
return gst_dp_payload_buffer (buffer, this->header_flag);
}
static GstBuffer *
gst_gdp_buffer_from_event (GstGDPPay * this, GstEvent * event)
{
return gst_dp_payload_event (event, this->header_flag);
}
static void
gdp_streamheader_array_append_take_buffer (GValue * array, GstBuffer * buf)
{
GValue value = { 0, };
g_value_init (&value, GST_TYPE_BUFFER);
gst_value_take_buffer (&value, buf);
gst_value_array_append_and_take_value (array, &value);
}
typedef struct
{
GstGDPPay *gdppay;
GValue *array;
} GstGDPPayAndArray;
static gboolean
gdp_streamheader_array_store_events (GstPad * pad, GstEvent ** event,
gpointer udata)
{
GstGDPPayAndArray *gdp_and_array = udata;
GstGDPPay *this = gdp_and_array->gdppay;
GValue *array = gdp_and_array->array;
GstBuffer *buf;
/* Need to handle caps differently to keep compatibility with 1.0 */
if (GST_EVENT_TYPE (*event) == GST_EVENT_CAPS) {
GstCaps *caps;
gst_event_parse_caps (*event, &caps);
buf = gst_gdp_buffer_from_caps (this, caps);
} else {
buf = gst_gdp_buffer_from_event (this, *event);
}
GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_HEADER);
gst_gdp_stamp_buffer (this, buf);
gdp_streamheader_array_append_take_buffer (array, buf);
return TRUE;
}
/* set our caps with streamheader, based on the latest newsegment and caps,
* and (possibly) GDP-serialized buffers of the streamheaders on the src pad */
static GstFlowReturn
gst_gdp_pay_reset_streamheader (GstGDPPay * this)
{
GstCaps *caps;
GstStructure *structure;
GstFlowReturn r = GST_FLOW_OK;
GstGDPPayAndArray gdp_and_array;
GValue array = { 0 };
gdp_and_array.gdppay = this;
gdp_and_array.array = &array;
GST_DEBUG_OBJECT (this, "start");
if (!this->have_segment || !this->have_caps || !this->have_streamstartid) {
GST_DEBUG_OBJECT (this, "1.0, missing new_segment or caps or stream "
"start id, returning");
return GST_FLOW_OK;
}
/* put copies of the buffers in a fixed list
* Stamp the buffers with offset and offset_end as well.
* We do this here so the offsets match the order the buffers go out in */
g_value_init (&array, GST_TYPE_ARRAY);
gst_pad_sticky_events_foreach (this->sinkpad,
gdp_streamheader_array_store_events, &gdp_and_array);
/* we also need to add GDP serializations of the streamheaders of the
* incoming caps */
structure = gst_caps_get_structure (this->caps, 0);
if (gst_structure_has_field (structure, "streamheader")) {
const GValue *sh;
GstBuffer *buffer;
int i, num;
sh = gst_structure_get_value (structure, "streamheader");
num = gst_value_array_get_size (sh);
GST_DEBUG_OBJECT (this,
"Need to serialize %d incoming streamheader buffers on ours", num);
for (i = 0; i < num; ++i) {
const GValue *bufval;
GstBuffer *outbuffer;
bufval = gst_value_array_get_value (sh, i);
buffer = gst_value_get_buffer (bufval);
/* Make copy before modifying buffer metadata */
buffer = gst_buffer_copy (buffer);
/* this buffer is deserialized by gdpdepay as a regular buffer,
it needs HEADER, because it's a streamheader - otherwise it
is mixed with regular data buffers */
GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_HEADER);
GST_BUFFER_OFFSET (buffer) = GST_BUFFER_OFFSET_NONE;
GST_BUFFER_OFFSET_END (buffer) = GST_BUFFER_OFFSET_NONE;
GST_BUFFER_TIMESTAMP (buffer) = GST_CLOCK_TIME_NONE;
outbuffer = gst_gdp_pay_buffer_from_buffer (this, buffer);
gst_buffer_unref (buffer);
if (!outbuffer) {
g_value_unset (&array);
goto no_buffer;
}
/* Setting HEADER as other GDP event buffers */
GST_DEBUG_OBJECT (this,
"Setting HEADER flag on outgoing buffer %" GST_PTR_FORMAT, outbuffer);
GST_BUFFER_FLAG_SET (outbuffer, GST_BUFFER_FLAG_HEADER);
GST_BUFFER_OFFSET (outbuffer) = GST_BUFFER_OFFSET_NONE;
GST_BUFFER_OFFSET_END (outbuffer) = GST_BUFFER_OFFSET_NONE;
GST_BUFFER_TIMESTAMP (outbuffer) = GST_CLOCK_TIME_NONE;
gdp_streamheader_array_append_take_buffer (&array, outbuffer);
}
} else {
GST_DEBUG_OBJECT (this, "no streamheader to serialize");
}
GST_DEBUG_OBJECT (this, "%d serialized buffers on streamheaders",
gst_value_array_get_size (&array));
caps = gst_caps_from_string ("application/x-gdp");
structure = gst_caps_get_structure (caps, 0);
gst_structure_set_value (structure, "streamheader", &array);
g_value_unset (&array);
GST_DEBUG_OBJECT (this, "Setting caps on src pad %" GST_PTR_FORMAT, caps);
gst_pad_set_caps (this->srcpad, caps);
/* if these are our first ever buffers, send out new_segment first */
if (!this->sent_streamheader) {
GstEvent *event;
GstSegment segment;
gst_segment_init (&segment, GST_FORMAT_BYTES);
event = gst_event_new_segment (&segment);
GST_DEBUG_OBJECT (this, "Sending out new_segment event %p", event);
if (!gst_pad_push_event (this->srcpad, event)) {
GST_WARNING_OBJECT (this, "pushing new segment failed");
r = GST_FLOW_ERROR;
goto done;
}
}
this->sent_streamheader = TRUE;
GST_DEBUG_OBJECT (this, "need to push %d queued buffers",
g_list_length (this->queue));
while (this->queue) {
GstBuffer *buffer;
buffer = GST_BUFFER_CAST (this->queue->data);
GST_DEBUG_OBJECT (this, "Pushing queued GDP buffer %p", buffer);
/* delete buffer from queue now */
this->queue = g_list_delete_link (this->queue, this->queue);
r = gst_pad_push (this->srcpad, buffer);
if (r != GST_FLOW_OK) {
GST_WARNING_OBJECT (this, "pushing queued GDP buffer returned %d", r);
goto done;
}
}
this->reset_streamheader = FALSE;
done:
gst_caps_unref (caps);
GST_DEBUG_OBJECT (this, "stop");
return r;
/* ERRORS */
no_buffer:
{
GST_ELEMENT_ERROR (this, STREAM, FORMAT, (NULL),
("failed to create GDP buffer from streamheader"));
return GST_FLOW_ERROR;
}
}
/* queue a buffer internally if we haven't sent streamheader buffers yet;
* otherwise, just push on, this takes ownership of the buffer. */
static GstFlowReturn
gst_gdp_queue_buffer (GstGDPPay * this, GstBuffer * buffer)
{
if (this->sent_streamheader && !this->reset_streamheader) {
GST_LOG_OBJECT (this, "Pushing GDP buffer %p, caps %" GST_PTR_FORMAT,
buffer, this->caps);
return gst_pad_push (this->srcpad, buffer);
}
/* store it on an internal queue. buffer remains reffed. */
this->queue = g_list_append (this->queue, buffer);
GST_DEBUG_OBJECT (this, "streamheader not sent yet or needs update, "
"queued buffer %p, now %d buffers queued",
buffer, g_list_length (this->queue));
return GST_FLOW_OK;
}
static GstFlowReturn
gst_gdp_pay_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer)
{
GstGDPPay *this;
GstBuffer *outbuffer;
GstFlowReturn ret;
this = GST_GDP_PAY (parent);
/* we should have received a new_segment before, otherwise it's a bug.
* fake one in that case */
if (!this->have_segment) {
GstEvent *event;
GstSegment segment;
GST_WARNING_OBJECT (this,
"did not receive new-segment before first buffer");
gst_segment_init (&segment, GST_FORMAT_BYTES);
event = gst_event_new_segment (&segment);
outbuffer = gst_gdp_buffer_from_event (this, event);
gst_event_unref (event);
/* GDP 0.2 doesn't know about new-segment, so this is not fatal */
if (!outbuffer) {
GST_ELEMENT_WARNING (this, STREAM, ENCODE, (NULL),
("Could not create GDP buffer from new segment event"));
} else {
GST_BUFFER_TIMESTAMP (outbuffer) = GST_BUFFER_TIMESTAMP (buffer);
GST_BUFFER_DURATION (outbuffer) = 0;
GST_BUFFER_FLAG_SET (outbuffer, GST_BUFFER_FLAG_HEADER);
GST_DEBUG_OBJECT (this, "Storing buffer %p as new_segment_buf",
outbuffer);
this->have_segment = TRUE;
}
}
/* make sure we've received caps before */
if (!this->caps)
goto no_caps;
/* create a GDP header packet,
* then create a GST buffer of the header packet and the buffer contents */
outbuffer = gst_gdp_pay_buffer_from_buffer (this, buffer);
if (!outbuffer)
goto no_buffer;
/* If the incoming buffer is HEADER, that means we have it on the caps
* as streamheader, and we have serialized a GDP version of it and put it
* on our caps */
if (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_HEADER)) {
GST_DEBUG_OBJECT (this, "Setting HEADER flag on outgoing buffer %p",
outbuffer);
GST_BUFFER_FLAG_SET (outbuffer, GST_BUFFER_FLAG_HEADER);
}
gst_gdp_stamp_buffer (this, outbuffer);
GST_BUFFER_TIMESTAMP (outbuffer) = GST_BUFFER_TIMESTAMP (buffer);
GST_BUFFER_DURATION (outbuffer) = GST_BUFFER_DURATION (buffer);
if (this->reset_streamheader)
gst_gdp_pay_reset_streamheader (this);
ret = gst_gdp_queue_buffer (this, outbuffer);
done:
gst_buffer_unref (buffer);
return ret;
/* ERRORS */
no_caps:
{
/* when returning a fatal error as a GstFlowReturn we must post an error
* message */
GST_ELEMENT_ERROR (this, STREAM, FORMAT, (NULL),
("first received buffer does not have caps set"));
ret = GST_FLOW_NOT_NEGOTIATED;
goto done;
}
no_buffer:
{
GST_ELEMENT_ERROR (this, STREAM, ENCODE, (NULL),
("Could not create GDP buffer from buffer"));
ret = GST_FLOW_ERROR;
goto done;
}
}
static gboolean
gst_gdp_pay_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstBuffer *outbuffer;
GstGDPPay *this = GST_GDP_PAY (parent);
GstFlowReturn flowret;
GstCaps *caps;
gboolean ret = TRUE;
GST_DEBUG_OBJECT (this, "received event %p of type %s (%d)",
event, gst_event_type_get_name (event->type), event->type);
/* now turn the event into a buffer */
outbuffer = gst_gdp_buffer_from_event (this, event);
if (!outbuffer)
goto no_outbuffer;
GST_BUFFER_TIMESTAMP (outbuffer) = GST_CLOCK_TIME_NONE;
GST_BUFFER_DURATION (outbuffer) = 0;
/* if we got a new segment or tag event, we should put it on our streamheader,
* and not send it on */
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_STREAM_START:
GST_DEBUG_OBJECT (this, "Received stream start id");
this->have_streamstartid = TRUE;
break;
case GST_EVENT_SEGMENT:
GST_DEBUG_OBJECT (this, "Received segment %" GST_PTR_FORMAT, event);
this->have_segment = TRUE;
break;
case GST_EVENT_CAPS:{
GST_DEBUG_OBJECT (this, "Received caps %" GST_PTR_FORMAT, event);
this->have_caps = TRUE;
gst_event_parse_caps (event, &caps);
gst_buffer_replace (&outbuffer, NULL);
if (this->caps == NULL || !gst_caps_is_equal (this->caps, caps)) {
GST_INFO_OBJECT (pad, "caps changed to %" GST_PTR_FORMAT, caps);
gst_caps_replace (&this->caps, caps);
outbuffer = gst_gdp_buffer_from_caps (this, caps);
if (outbuffer == NULL)
goto no_buffer_from_caps;
GST_BUFFER_DURATION (outbuffer) = 0;
}
break;
}
default:
break;
}
if (GST_EVENT_IS_STICKY (event)) {
GST_BUFFER_FLAG_SET (outbuffer, GST_BUFFER_FLAG_HEADER);
this->reset_streamheader = TRUE;
}
/* if we have EOS, we should send on EOS ourselves */
if (GST_EVENT_TYPE (event) == GST_EVENT_EOS
|| GST_EVENT_TYPE (event) == GST_EVENT_STREAM_START) {
GST_DEBUG_OBJECT (this, "Sending on event %" GST_PTR_FORMAT, event);
/* ref, we unref later again */
ret = gst_pad_push_event (this->srcpad, gst_event_ref (event));
}
if (GST_EVENT_TYPE (event) != GST_EVENT_EOS) {
GST_DEBUG_OBJECT (this, "queuing GDP buffer %p of event %p", outbuffer,
event);
flowret = gst_gdp_queue_buffer (this, outbuffer);
if (flowret != GST_FLOW_OK)
goto push_error;
} else {
gst_buffer_unref (outbuffer);
}
done:
gst_event_unref (event);
return ret;
/* ERRORS */
no_outbuffer:
{
GST_ELEMENT_WARNING (this, STREAM, ENCODE, (NULL),
("Could not create GDP buffer from received event (type %s)",
gst_event_type_get_name (event->type)));
ret = FALSE;
goto done;
}
no_buffer_from_caps:
{
GST_ELEMENT_ERROR (this, STREAM, ENCODE, (NULL),
("Could not create GDP buffer from caps %" GST_PTR_FORMAT, caps));
ret = FALSE;
goto done;
}
push_error:
{
GST_WARNING_OBJECT (this, "queueing GDP event buffer returned %d", flowret);
ret = FALSE;
goto done;
}
}
static gboolean
gst_gdp_pay_src_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstGDPPay *this;
gboolean res = TRUE;
this = GST_GDP_PAY (parent);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_SEEK:
/* we refuse seek for now. */
gst_event_unref (event);
res = FALSE;
break;
case GST_EVENT_QOS:
case GST_EVENT_NAVIGATION:
default:
/* everything else is passed */
res = gst_pad_push_event (this->sinkpad, event);
break;
}
return res;
}
static void
gst_gdp_pay_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstGDPPay *this;
g_return_if_fail (GST_IS_GDP_PAY (object));
this = GST_GDP_PAY (object);
switch (prop_id) {
case PROP_CRC_HEADER:
this->crc_header =
g_value_get_boolean (value) ? GST_DP_HEADER_FLAG_CRC_HEADER : 0;
this->header_flag = this->crc_header | this->crc_payload;
break;
case PROP_CRC_PAYLOAD:
this->crc_payload =
g_value_get_boolean (value) ? GST_DP_HEADER_FLAG_CRC_PAYLOAD : 0;
this->header_flag = this->crc_header | this->crc_payload;
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_gdp_pay_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstGDPPay *this;
g_return_if_fail (GST_IS_GDP_PAY (object));
this = GST_GDP_PAY (object);
switch (prop_id) {
case PROP_CRC_HEADER:
g_value_set_boolean (value, this->crc_header);
break;
case PROP_CRC_PAYLOAD:
g_value_set_boolean (value, this->crc_payload);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static GstStateChangeReturn
gst_gdp_pay_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret;
GstGDPPay *this = GST_GDP_PAY (element);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_PAUSED:
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_gdp_pay_reset (this);
break;
default:
break;
}
return ret;
}