rtpmanager: Add header extension implementation for the 64-bit RFC6051 NTP header extension

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/2132>

subprojects/gst-plugins-good/docs/gst_plugins_cache.json

@@ -17948,6 +17948,50 @@
                 },
                 "rank": "marginal"
             },
+            "rtphdrextntp64": {
+                "RTP-Header-Extension-URI": "urn:ietf:params:rtp-hdrext:ntp-64",
+                "author": "Sebastian Dröge <sebastian@centricular.com>",
+                "description": "Extends RTP packets to add or retrieve a 64-bit NTP timestamp as specified in RFC6501",
+                "hierarchy": [
+                    "GstRTPHeaderExtensionNtp64",
+                    "GstRTPHeaderExtension",
+                    "GstElement",
+                    "GstObject",
+                    "GInitiallyUnowned",
+                    "GObject"
+                ],
+                "klass": "Network/Extension/RTPHeader",
+                "long-name": "RTP Header Extension RFC6051 64-bit NTP timestamp",
+                "properties": {
+                    "every-packet": {
+                        "blurb": "Add the header extension to every packet",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "false",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "interval": {
+                        "blurb": "Interval between consecutive packets that get the header extension added",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "0",
+                        "max": "18446744073709551615",
+                        "min": "0",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "guint64",
+                        "writable": true
+                    }
+                },
+                "rank": "marginal"
+            },
             "rtphdrextrepairedstreamid": {
                 "RTP-Header-Extension-URI": "urn:ietf:params:rtp-hdrext:sdes:repaired-rtp-stream-id",
                 "author": "Matthew Waters <matthew@centricular.com>",

subprojects/gst-plugins-good/gst/rtpmanager/gstrtphdrext-ntp.c

@@ -0,0 +1,269 @@
+/* GStreamer
+ * Copyright (C) <2022> Sebastian Dröge <sebastian@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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * SECTION:element-rtphdrextntp64
+ * @title: rtphdrextntp64
+ * @short_description: RTP Header Extension for RFC6051 64-bit NTP timestamps for rapid synchronization.
+ * @see_also: #GstRTPHeaderExtension, #GstRTPBasePayload, #GstRTPBaseDepayload, gstrtpbuffer
+ *
+ * Since: 1.22
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/rtp/gstrtpbuffer.h>
+
+#include "gstrtphdrext-ntp.h"
+
+GST_DEBUG_CATEGORY_STATIC (rtphdrext_ntp_debug);
+#define GST_CAT_DEFAULT (rtphdrext_ntp_debug)
+
+enum
+{
+  PROP_0,
+  PROP_INTERVAL,
+  PROP_EVERY_PACKET,
+};
+
+#define DEFAULT_INTERVAL 0
+#define DEFAULT_EVERY_PACKET FALSE
+
+static GstStaticCaps ntp_reference_timestamp_caps =
+GST_STATIC_CAPS ("timestamp/x-ntp");
+
+struct _GstRTPHeaderExtensionNtp64
+{
+  GstRTPHeaderExtension parent;
+
+  GstClockTime last_pts;
+
+  GstClockTime interval;
+  gboolean every_packet;
+};
+
+G_DEFINE_TYPE_WITH_CODE (GstRTPHeaderExtensionNtp64,
+    gst_rtp_header_extension_ntp_64,
+    GST_TYPE_RTP_HEADER_EXTENSION, GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT,
+        "rtphdrextntp", 0, "RTP RFC6051 NTP Timestamps Header Extension");
+    );
+
+GST_ELEMENT_REGISTER_DEFINE (rtphdrextntp64,
+    "rtphdrextntp64", GST_RANK_MARGINAL, GST_TYPE_RTP_HEADER_EXTENSION_NTP_64);
+
+static GstRTPHeaderExtensionFlags
+    gst_rtp_header_extension_ntp_get_supported_flags
+    (GstRTPHeaderExtension * ext)
+{
+  return GST_RTP_HEADER_EXTENSION_ONE_BYTE | GST_RTP_HEADER_EXTENSION_TWO_BYTE;
+}
+
+static gsize
+    gst_rtp_header_extension_ntp_64_get_max_size
+    (GstRTPHeaderExtension * ext, const GstBuffer * buffer)
+{
+  return 8;
+}
+
+static gssize
+gst_rtp_header_extension_ntp_64_write (GstRTPHeaderExtension
+    * ext, const GstBuffer * input_meta, GstRTPHeaderExtensionFlags write_flags,
+    GstBuffer * output, guint8 * data, gsize size)
+{
+  GstRTPHeaderExtensionNtp64 *self = GST_RTP_HEADER_EXTENSION_NTP_64 (ext);
+
+  g_return_val_if_fail (size >=
+      gst_rtp_header_extension_ntp_64_get_max_size (ext, NULL), -1);
+  g_return_val_if_fail (write_flags &
+      gst_rtp_header_extension_ntp_get_supported_flags (ext), -1);
+
+  if (self->every_packet
+      || self->last_pts == GST_CLOCK_TIME_NONE
+      || !GST_BUFFER_PTS_IS_VALID (input_meta)
+      || (self->last_pts != GST_BUFFER_PTS (input_meta)
+          && (GST_BUFFER_IS_DISCONT (input_meta)
+              || (GST_BUFFER_PTS (input_meta) >= self->last_pts
+                  && GST_BUFFER_PTS (input_meta) - self->last_pts >=
+                  self->interval)))) {
+    GstCaps *caps;
+    GstReferenceTimestampMeta *meta;
+
+    caps = gst_static_caps_get (&ntp_reference_timestamp_caps);
+    meta =
+        gst_buffer_get_reference_timestamp_meta ((GstBuffer *) input_meta,
+        caps);
+    if (meta) {
+      guint64 ntptime =
+          gst_util_uint64_scale (meta->timestamp, G_GUINT64_CONSTANT (1) << 32,
+          GST_SECOND);
+
+      GST_WRITE_UINT64_BE (data, ntptime);
+    } else {
+      memset (data, 0, 8);
+    }
+    gst_caps_unref (caps);
+    self->last_pts = GST_BUFFER_PTS (input_meta);
+    return 8;
+  } else {
+    return 0;
+  }
+}
+
+static gboolean
+gst_rtp_header_extension_ntp_64_read (GstRTPHeaderExtension
+    * ext, GstRTPHeaderExtensionFlags read_flags, const guint8 * data,
+    gsize size, GstBuffer * buffer)
+{
+  GstCaps *caps;
+  guint64 ntptime;
+  GstClockTime timestamp;
+
+  if (size < 8)
+    return FALSE;
+
+  caps = gst_static_caps_get (&ntp_reference_timestamp_caps);
+
+  ntptime = GST_READ_UINT64_BE (data);
+  timestamp =
+      gst_util_uint64_scale (ntptime, GST_SECOND, G_GUINT64_CONSTANT (1) << 32);
+
+  gst_buffer_add_reference_timestamp_meta (buffer, caps, timestamp,
+      GST_CLOCK_TIME_NONE);
+
+  gst_caps_unref (caps);
+
+  return TRUE;
+}
+
+
+static void
+gst_rtp_header_extension_ntp_64_get_property (GObject *
+    object, guint prop_id, GValue * value, GParamSpec * pspec)
+{
+  GstRTPHeaderExtensionNtp64 *self = GST_RTP_HEADER_EXTENSION_NTP_64 (object);
+
+  switch (prop_id) {
+    case PROP_INTERVAL:
+      GST_OBJECT_LOCK (self);
+      g_value_set_uint64 (value, self->interval);
+      GST_OBJECT_UNLOCK (self);
+      break;
+    case PROP_EVERY_PACKET:
+      GST_OBJECT_LOCK (self);
+      g_value_set_boolean (value, self->every_packet);
+      GST_OBJECT_UNLOCK (self);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_rtp_header_extension_ntp_64_set_property (GObject *
+    object, guint prop_id, const GValue * value, GParamSpec * pspec)
+{
+  GstRTPHeaderExtensionNtp64 *self = GST_RTP_HEADER_EXTENSION_NTP_64 (object);
+
+  switch (prop_id) {
+    case PROP_INTERVAL:
+      GST_OBJECT_LOCK (self);
+      self->interval = g_value_get_uint64 (value);
+      GST_OBJECT_UNLOCK (self);
+      break;
+    case PROP_EVERY_PACKET:
+      GST_OBJECT_LOCK (self);
+      self->every_packet = g_value_get_boolean (value);
+      GST_OBJECT_UNLOCK (self);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+    gst_rtp_header_extension_ntp_64_class_init
+    (GstRTPHeaderExtensionNtp64Class * klass)
+{
+  GstRTPHeaderExtensionClass *rtp_hdr_class;
+  GstElementClass *gstelement_class;
+  GObjectClass *gobject_class;
+
+  rtp_hdr_class = (GstRTPHeaderExtensionClass *) klass;
+  gobject_class = (GObjectClass *) klass;
+  gstelement_class = (GstElementClass *) klass;
+
+  gobject_class->set_property = gst_rtp_header_extension_ntp_64_set_property;
+  gobject_class->get_property = gst_rtp_header_extension_ntp_64_get_property;
+
+  /**
+   * rtphdrextntp64:interval:
+   *
+   * The minimum interval between packets that get the header extension added.
+   *
+   * On discontinuities the interval will be reset and the next packet gets
+   * the header extension added.
+   *
+   * Since: 1.22
+   */
+  g_object_class_install_property (gobject_class, PROP_INTERVAL,
+      g_param_spec_uint64 ("interval", "Interval",
+          "Interval between consecutive packets that get the header extension added",
+          0, G_MAXUINT64, DEFAULT_INTERVAL,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+  /**
+   * rtphdrextntp64:every-packet:
+   *
+   * If set to %TRUE the header extension will be added to every packet,
+   * independent of its timestamp. By default only the first packet with a
+   * given timestamp will get the header extension added.
+   *
+   * Since: 1.22
+   */
+  g_object_class_install_property (gobject_class, PROP_EVERY_PACKET,
+      g_param_spec_boolean ("every-packet", "Every Packet",
+          "Add the header extension to every packet", DEFAULT_EVERY_PACKET,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+  rtp_hdr_class->get_supported_flags =
+      gst_rtp_header_extension_ntp_get_supported_flags;
+  rtp_hdr_class->get_max_size = gst_rtp_header_extension_ntp_64_get_max_size;
+  rtp_hdr_class->write = gst_rtp_header_extension_ntp_64_write;
+  rtp_hdr_class->read = gst_rtp_header_extension_ntp_64_read;
+
+  gst_element_class_set_static_metadata (gstelement_class,
+      "RTP Header Extension RFC6051 64-bit NTP timestamp",
+      GST_RTP_HDREXT_ELEMENT_CLASS,
+      "Extends RTP packets to add or retrieve a 64-bit NTP "
+      "timestamp as specified in RFC6501",
+      "Sebastian Dröge <sebastian@centricular.com>");
+  gst_rtp_header_extension_class_set_uri (rtp_hdr_class,
+      GST_RTP_HDREXT_BASE GST_RTP_HDREXT_NTP_64);
+}
+
+static void
+gst_rtp_header_extension_ntp_64_init (GstRTPHeaderExtensionNtp64 * self)
+{
+  self->last_pts = GST_CLOCK_TIME_NONE;
+  self->interval = DEFAULT_INTERVAL;
+  self->every_packet = DEFAULT_EVERY_PACKET;
+}

subprojects/gst-plugins-good/gst/rtpmanager/gstrtphdrext-ntp.h

@@ -0,0 +1,36 @@
+/* GStreamer
+ * Copyright (C) <2022> Sebastian Dröge <sebastian@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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef __GST_RTPHDREXT_NTP_H__
+#define __GST_RTPHDREXT_NTP_H__
+
+#include <gst/gst.h>
+#include <gst/rtp/gstrtphdrext.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_RTP_HEADER_EXTENSION_NTP_64 (gst_rtp_header_extension_ntp_64_get_type())
+
+G_DECLARE_FINAL_TYPE (GstRTPHeaderExtensionNtp64, gst_rtp_header_extension_ntp_64, GST, RTP_HEADER_EXTENSION_NTP_64, GstRTPHeaderExtension);
+
+GST_ELEMENT_REGISTER_DECLARE (rtphdrextntp64);
+
+G_END_DECLS
+
+#endif /* __GST_RTPHDREXT_NTP_H__ */

subprojects/gst-plugins-good/gst/rtpmanager/gstrtpmanager.c

@@ -37,6 +37,7 @@
 #include "gstrtphdrext-twcc.h"
 #include "gstrtphdrext-clientaudiolevel.h"
 #include "gstrtphdrext-mid.h"
+#include "gstrtphdrext-ntp.h"
 #include "gstrtphdrext-repairedstreamid.h"
 #include "gstrtphdrext-streamid.h"
 
@@ -61,6 +62,7 @@ plugin_init (GstPlugin * plugin)
   ret |= GST_ELEMENT_REGISTER (rtphdrexttwcc, plugin);
   ret |= GST_ELEMENT_REGISTER (rtphdrextclientaudiolevel, plugin);
   ret |= GST_ELEMENT_REGISTER (rtphdrextmid, plugin);
+  ret |= GST_ELEMENT_REGISTER (rtphdrextntp64, plugin);
   ret |= GST_ELEMENT_REGISTER (rtphdrextstreamid, plugin);
   ret |= GST_ELEMENT_REGISTER (rtphdrextrepairedstreamid, plugin);
 

subprojects/gst-plugins-good/gst/rtpmanager/meson.build

@@ -6,6 +6,7 @@ rtpmanager_sources = [
   'gstrtphdrext-twcc.c',
   'gstrtphdrext-clientaudiolevel.c',
   'gstrtphdrext-mid.c',
+  'gstrtphdrext-ntp.c',
   'gstrtphdrext-repairedstreamid.c',
   'gstrtphdrext-streamid.c',
   'gstrtpmux.c',