gstreamer/ext/avtp/gstavtpbasepayload.c

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avtp: Introduce AAF payloader element This patch introduces the AVTP Audio Format (AAF) payloader element from the AVTP plugin. The element inputs audio raw data and outputs AVTP packets (aka AVTPDUs), implementing a typical protocol payloader element from GStreamer. AAF is one of the available formats to transport audio data in an AVTP system. AAF is specified in IEEE 1722-2016 section 7 and provides two encapsulation mode: PCM and AES3. This patch implements PCM encapsulation mode only. The AAF payloader working mechanism consists of building the AAF header, prepending it to the GstBuffer received on the sink pad, and pushing the buffer downstream. Payloader parameters such as stream ID, maximum transit time, time uncertainty, and timestamping mode are passed via element properties. AAF doesn't support all possible sample format and sampling rate values so the sink pad caps template from the payloader is a subset of audio/x-raw. Additionally, this patch implements only "normal" timestamping mode from AAF. "Sparse" mode should be implemented in future. Upcoming patches will introduce other AVTP payloader elements that will have some common code. For that reason, this patch introduces the GstAvtpBasePayload abstract class that implements common payloader functionalities, and the GstAvtpAafPay class that extends the GstAvtpBasePayload class, implementing AAF-specific functionalities. The AAF payloader element is most likely to be used with the AVTP sink element (to be introduced by a later patch) but it could also be used with UDP sink element to implement AVTP over UDP as described in IEEE 1722-2016 Annex J. This element was inspired by RTP payloader elements.
2019-01-17 01:16:59 +00:00
/*
* GStreamer AVTP Plugin
* Copyright (C) 2019 Intel Corporation
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA
*/
#include "gstavtpbasepayload.h"
GST_DEBUG_CATEGORY_STATIC (avtpbasepayload_debug);
#define GST_CAT_DEFAULT (avtpbasepayload_debug)
#define DEFAULT_STREAMID 0xAABBCCDDEEFF0000
#define DEFAULT_MTT 50000000
#define DEFAULT_TU 1000000
#define DEFAULT_PROCESSING_DEADLINE (20 * GST_MSECOND)
enum
{
PROP_0,
PROP_STREAMID,
PROP_MTT,
PROP_TU,
PROP_PROCESSING_DEADLINE,
};
static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-avtp")
);
static void gst_avtp_base_payload_class_init (GstAvtpBasePayloadClass * klass);
static void gst_avtp_base_payload_init (GstAvtpBasePayload * avtpbasepayload,
gpointer g_class);
static void gst_avtp_base_payload_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_avtp_base_payload_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static gboolean gst_avtp_base_payload_sink_event (GstPad * pad,
GstObject * parent, GstEvent * event);
GType
gst_avtp_base_payload_get_type (void)
{
static GType avtpbasepayload_type = 0;
if (g_once_init_enter ((gsize *) & avtpbasepayload_type)) {
static const GTypeInfo avtpbasepayload_info = {
sizeof (GstAvtpBasePayloadClass),
NULL,
NULL,
(GClassInitFunc) gst_avtp_base_payload_class_init,
NULL,
NULL,
sizeof (GstAvtpBasePayload),
0,
(GInstanceInitFunc) gst_avtp_base_payload_init,
};
GType _type;
_type = g_type_register_static (GST_TYPE_ELEMENT, "GstAvtpBasePayload",
&avtpbasepayload_info, G_TYPE_FLAG_ABSTRACT);
g_once_init_leave ((gsize *) & avtpbasepayload_type, _type);
}
return avtpbasepayload_type;
}
static void
gst_avtp_base_payload_class_init (GstAvtpBasePayloadClass * klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->set_property = gst_avtp_base_payload_set_property;
object_class->get_property = gst_avtp_base_payload_get_property;
g_object_class_install_property (object_class, PROP_STREAMID,
g_param_spec_uint64 ("streamid", "Stream ID",
"Stream ID associated with the AVTPDU", 0, G_MAXUINT64,
DEFAULT_STREAMID, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
GST_PARAM_MUTABLE_READY));
g_object_class_install_property (object_class, PROP_MTT,
g_param_spec_uint ("mtt", "Maximum Transit Time",
"Maximum Transit Time (MTT) in nanoseconds", 0,
G_MAXUINT, DEFAULT_MTT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (object_class, PROP_TU,
g_param_spec_uint ("tu", "Timing Uncertainty",
"Timing Uncertainty (TU) in nanoseconds", 0,
G_MAXUINT, DEFAULT_TU, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (object_class, PROP_PROCESSING_DEADLINE,
g_param_spec_uint64 ("processing-deadline", "Processing deadline",
"Maximum amount of time (in ns) the pipeline can take for processing the buffer",
0, G_MAXUINT64, DEFAULT_PROCESSING_DEADLINE, G_PARAM_READWRITE |
G_PARAM_STATIC_STRINGS));
klass->chain = NULL;
klass->sink_event = GST_DEBUG_FUNCPTR (gst_avtp_base_payload_sink_event);
GST_DEBUG_CATEGORY_INIT (avtpbasepayload_debug, "avtpbasepayload", 0,
"Base class for AVTP payloaders");
gst_type_mark_as_plugin_api (GST_TYPE_AVTP_BASE_PAYLOAD, 0);
avtp: Introduce AAF payloader element This patch introduces the AVTP Audio Format (AAF) payloader element from the AVTP plugin. The element inputs audio raw data and outputs AVTP packets (aka AVTPDUs), implementing a typical protocol payloader element from GStreamer. AAF is one of the available formats to transport audio data in an AVTP system. AAF is specified in IEEE 1722-2016 section 7 and provides two encapsulation mode: PCM and AES3. This patch implements PCM encapsulation mode only. The AAF payloader working mechanism consists of building the AAF header, prepending it to the GstBuffer received on the sink pad, and pushing the buffer downstream. Payloader parameters such as stream ID, maximum transit time, time uncertainty, and timestamping mode are passed via element properties. AAF doesn't support all possible sample format and sampling rate values so the sink pad caps template from the payloader is a subset of audio/x-raw. Additionally, this patch implements only "normal" timestamping mode from AAF. "Sparse" mode should be implemented in future. Upcoming patches will introduce other AVTP payloader elements that will have some common code. For that reason, this patch introduces the GstAvtpBasePayload abstract class that implements common payloader functionalities, and the GstAvtpAafPay class that extends the GstAvtpBasePayload class, implementing AAF-specific functionalities. The AAF payloader element is most likely to be used with the AVTP sink element (to be introduced by a later patch) but it could also be used with UDP sink element to implement AVTP over UDP as described in IEEE 1722-2016 Annex J. This element was inspired by RTP payloader elements.
2019-01-17 01:16:59 +00:00
}
static void
gst_avtp_base_payload_init (GstAvtpBasePayload * avtpbasepayload,
gpointer g_class)
{
GstPadTemplate *templ;
GstElement *element = GST_ELEMENT (avtpbasepayload);
GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
GstAvtpBasePayloadClass *avtpbasepayload_class =
GST_AVTP_BASE_PAYLOAD_CLASS (g_class);
g_assert (avtpbasepayload_class->chain != NULL);
avtpbasepayload->srcpad = gst_pad_new_from_static_template (&src_template,
"src");
gst_element_add_pad (element, avtpbasepayload->srcpad);
templ = gst_element_class_get_pad_template (element_class, "sink");
g_assert (templ != NULL);
avtpbasepayload->sinkpad = gst_pad_new_from_template (templ, "sink");
gst_pad_set_chain_function (avtpbasepayload->sinkpad,
avtpbasepayload_class->chain);
gst_pad_set_event_function (avtpbasepayload->sinkpad,
avtpbasepayload_class->sink_event);
gst_element_add_pad (element, avtpbasepayload->sinkpad);
avtpbasepayload->streamid = DEFAULT_STREAMID;
avtpbasepayload->mtt = DEFAULT_MTT;
avtpbasepayload->tu = DEFAULT_TU;
avtpbasepayload->processing_deadline = DEFAULT_PROCESSING_DEADLINE;
avtpbasepayload->latency = GST_CLOCK_TIME_NONE;
avtpbasepayload->seqnum = 0;
gst_segment_init (&avtpbasepayload->segment, GST_FORMAT_UNDEFINED);
}
static void
gst_avtp_base_payload_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstAvtpBasePayload *avtpbasepayload = GST_AVTP_BASE_PAYLOAD (object);
GST_DEBUG_OBJECT (avtpbasepayload, "prop_id %u", prop_id);
switch (prop_id) {
case PROP_STREAMID:
avtpbasepayload->streamid = g_value_get_uint64 (value);
break;
case PROP_MTT:
avtpbasepayload->mtt = g_value_get_uint (value);
break;
case PROP_TU:
avtpbasepayload->tu = g_value_get_uint (value);
break;
case PROP_PROCESSING_DEADLINE:
avtpbasepayload->processing_deadline = g_value_get_uint64 (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_avtp_base_payload_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstAvtpBasePayload *avtpbasepayload = GST_AVTP_BASE_PAYLOAD (object);
GST_DEBUG_OBJECT (avtpbasepayload, "prop_id %u", prop_id);
switch (prop_id) {
case PROP_STREAMID:
g_value_set_uint64 (value, avtpbasepayload->streamid);
break;
case PROP_MTT:
g_value_set_uint (value, avtpbasepayload->mtt);
break;
case PROP_TU:
g_value_set_uint (value, avtpbasepayload->tu);
break;
case PROP_PROCESSING_DEADLINE:
g_value_set_uint64 (value, avtpbasepayload->processing_deadline);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static gboolean
gst_avtp_base_payload_sink_event (GstPad * pad, GstObject * parent,
GstEvent * event)
{
GstAvtpBasePayload *avtpbasepayload = GST_AVTP_BASE_PAYLOAD (parent);
GST_DEBUG_OBJECT (avtpbasepayload, "event %s", GST_EVENT_TYPE_NAME (event));
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_SEGMENT:
gst_event_copy_segment (event, &avtpbasepayload->segment);
/* Fall through */
default:
return gst_pad_event_default (pad, parent, event);
}
}
GstClockTime
gst_avtp_base_payload_calc_ptime (GstAvtpBasePayload * avtpbasepayload,
GstBuffer * buffer)
{
GstClockTime base_time, running_time;
g_assert (GST_BUFFER_PTS (buffer) != GST_CLOCK_TIME_NONE);
if (G_UNLIKELY (avtpbasepayload->latency == GST_CLOCK_TIME_NONE)) {
GstQuery *query;
query = gst_query_new_latency ();
if (!gst_pad_peer_query (avtpbasepayload->sinkpad, query))
return GST_CLOCK_TIME_NONE;
gst_query_parse_latency (query, NULL, &avtpbasepayload->latency, NULL);
gst_query_unref (query);
GST_DEBUG_OBJECT (avtpbasepayload, "latency %" GST_TIME_FORMAT,
GST_TIME_ARGS (avtpbasepayload->latency));
}
base_time = gst_element_get_base_time (GST_ELEMENT (avtpbasepayload));
running_time = gst_segment_to_running_time (&avtpbasepayload->segment,
avtpbasepayload->segment.format, GST_BUFFER_PTS (buffer));
return base_time + running_time + avtpbasepayload->latency +
avtpbasepayload->processing_deadline + avtpbasepayload->mtt +
avtpbasepayload->tu;
}