Ejemplo n.º 1
1
/* The create() virtual function is responsible for returning the next buffer.
 * We just pop buffers off of the queue and block if necessary.
 */
static GstFlowReturn
shell_recorder_src_create (GstPushSrc  *push_src,
			   GstBuffer  **buffer_out)
{
  ShellRecorderSrc *src = SHELL_RECORDER_SRC (push_src);
  GstBuffer *buffer;

  if (src->closed)
    return GST_FLOW_EOS;

  buffer = g_async_queue_pop (src->queue);

  if (src->last_frame_time == 0)
    src->last_frame_time = gst_clock_get_time (GST_CLOCK (src->clock));

  if (buffer == RECORDER_QUEUE_END)
    {
      /* Returning UNEXPECTED here will cause a EOS message to be sent */
      src->closed = TRUE;
      return GST_FLOW_EOS;
    }

  shell_recorder_src_update_memory_used (src,
					 - (int)(gst_buffer_get_size(buffer) / 1024));

  *buffer_out = buffer;
  GST_BUFFER_DURATION(*buffer_out) = GST_CLOCK_DIFF (src->last_frame_time, gst_clock_get_time (GST_CLOCK (src->clock)));

  src->last_frame_time = gst_clock_get_time (GST_CLOCK (src->clock));

  return GST_FLOW_OK;
}
Ejemplo n.º 2
0
/**
 * gst_net_client_clock_new:
 * @name: a name for the clock
 * @remote_address: the address of the remote clock provider
 * @remote_port: the port of the remote clock provider
 * @base_time: initial time of the clock
 *
 * Create a new #GstNetClientClock that will report the time
 * provided by the #GstNetClockProvider on @remote_address and 
 * @remote_port.
 *
 * Returns: a new #GstClock that receives a time from the remote
 * clock.
 */
GstClock *
gst_net_client_clock_new (gchar * name, const gchar * remote_address,
    gint remote_port, GstClockTime base_time)
{
  GstNetClientClock *ret;
  GstClockTime internal;

  g_return_val_if_fail (remote_address != NULL, NULL);
  g_return_val_if_fail (remote_port > 0, NULL);
  g_return_val_if_fail (remote_port <= G_MAXUINT16, NULL);
  g_return_val_if_fail (base_time != GST_CLOCK_TIME_NONE, NULL);

  ret = g_object_new (GST_TYPE_NET_CLIENT_CLOCK, "address", remote_address,
      "port", remote_port, NULL);

  /* gst_clock_get_time() values are guaranteed to be increasing. because no one
   * has called get_time on this clock yet we are free to adjust to any value
   * without worrying about worrying about MAX() issues with the clock's
   * internal time.
   */

  /* update our internal time so get_time() give something around base_time.
     assume that the rate is 1 in the beginning. */
  internal = gst_clock_get_internal_time (GST_CLOCK (ret));
  gst_clock_set_calibration (GST_CLOCK (ret), internal, base_time, 1, 1);

  {
    GstClockTime now = gst_clock_get_time (GST_CLOCK (ret));

    if (now < base_time || now > base_time + GST_SECOND)
      g_warning ("unable to set the base time, expect sync problems!");
  }

  if ((ret->priv->fdset = gst_poll_new (TRUE)) == NULL)
    goto no_fdset;

  if (!gst_net_client_clock_start (ret))
    goto failed_start;

  /* all systems go, cap'n */
  return (GstClock *) ret;

no_fdset:
  {
    GST_ERROR_OBJECT (ret, "could not create an fdset: %s (%d)",
        g_strerror (errno), errno);
    gst_object_unref (ret);
    return NULL;
  }
failed_start:
  {
    /* already printed a nice error */
    gst_object_unref (ret);
    return NULL;
  }
}
Ejemplo n.º 3
0
/**
 * gst_net_client_clock_new:
 * @name: a name for the clock
 * @remote_address: the address of the remote clock provider
 * @remote_port: the port of the remote clock provider
 * @base_time: initial time of the clock
 *
 * Create a new #GstNetClientClock that will report the time
 * provided by the #GstNetTimeProvider on @remote_address and 
 * @remote_port.
 *
 * Returns: a new #GstClock that receives a time from the remote
 * clock.
 */
GstClock *
gst_net_client_clock_new (gchar * name, const gchar * remote_address,
    gint remote_port, GstClockTime base_time)
{
  /* FIXME: gst_net_client_clock_new() should be a thin wrapper for g_object_new() */
  GstNetClientClock *ret;
  GstClockTime internal;

  g_return_val_if_fail (remote_address != NULL, NULL);
  g_return_val_if_fail (remote_port > 0, NULL);
  g_return_val_if_fail (remote_port <= G_MAXUINT16, NULL);
  g_return_val_if_fail (base_time != GST_CLOCK_TIME_NONE, NULL);

  ret = g_object_new (GST_TYPE_NET_CLIENT_CLOCK, "address", remote_address,
      "port", remote_port, NULL);

  /* gst_clock_get_time() values are guaranteed to be increasing. because no one
   * has called get_time on this clock yet we are free to adjust to any value
   * without worrying about worrying about MAX() issues with the clock's
   * internal time.
   */

  /* update our internal time so get_time() give something around base_time.
     assume that the rate is 1 in the beginning. */
  internal = gst_clock_get_internal_time (GST_CLOCK (ret));
  gst_clock_set_calibration (GST_CLOCK (ret), internal, base_time, 1, 1);

  {
    GstClockTime now = gst_clock_get_time (GST_CLOCK (ret));

    if (GST_CLOCK_DIFF (now, base_time) > 0 ||
        GST_CLOCK_DIFF (now, base_time + GST_SECOND) < 0) {
      g_warning ("unable to set the base time, expect sync problems!");
    }
  }

  if (!gst_net_client_clock_start (ret))
    goto failed_start;

  /* all systems go, cap'n */
  return (GstClock *) ret;

failed_start:
  {
    /* already printed a nice error */
    gst_object_unref (ret);
    return NULL;
  }
}
Ejemplo n.º 4
0
int
main (void)
{
  GstClock *clock;
  gboolean lockstep = TRUE;

  clock = GST_CLOCK (g_object_new (LP_TYPE_CLOCK, NULL));
  g_assert_nonnull (clock);

  g_object_get (clock, "lockstep", &lockstep, NULL);
  g_assert (!lockstep);

  g_object_set (clock, "lockstep", TRUE, NULL);
  g_object_get (clock, "lockstep", &lockstep, NULL);
  g_assert (lockstep);

  lockstep = FALSE;
  g_object_set (clock, "lockstep", TRUE, NULL); /* vacuous set */
  g_object_get (clock, "lockstep", &lockstep, NULL);
  g_assert (lockstep);

  g_object_unref (clock);

  exit (EXIT_SUCCESS);
}
Ejemplo n.º 5
0
static void
gst_clock_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec)
{
  GstClock *clock;

  clock = GST_CLOCK (object);

  switch (prop_id) {
    case PROP_STATS:
      GST_OBJECT_LOCK (clock);
      g_value_set_boolean (value, clock->stats);
      GST_OBJECT_UNLOCK (clock);
      break;
    case PROP_WINDOW_SIZE:
      GST_CLOCK_SLAVE_LOCK (clock);
      g_value_set_int (value, clock->window_size);
      GST_CLOCK_SLAVE_UNLOCK (clock);
      break;
    case PROP_WINDOW_THRESHOLD:
      GST_CLOCK_SLAVE_LOCK (clock);
      g_value_set_int (value, clock->window_threshold);
      GST_CLOCK_SLAVE_UNLOCK (clock);
      break;
    case PROP_TIMEOUT:
      GST_CLOCK_SLAVE_LOCK (clock);
      g_value_set_uint64 (value, clock->timeout);
      GST_CLOCK_SLAVE_UNLOCK (clock);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}
Ejemplo n.º 6
0
static GstClock *
alsaspdifsink_provide_clock (GstElement * elem)
{
  AlsaSPDIFSink *sink = ALSASPDIFSINK (elem);

  return GST_CLOCK (gst_object_ref (sink->clock));
}
static void
process_entry_context_unlocked (GstTestClock * test_clock,
    GstClockEntryContext * ctx)
{
  GstTestClockPrivate *priv = GST_TEST_CLOCK_GET_PRIVATE (test_clock);
  GstClockEntry *entry = ctx->clock_entry;

  if (ctx->time_diff >= 0)
    GST_CLOCK_ENTRY_STATUS (entry) = GST_CLOCK_OK;
  else
    GST_CLOCK_ENTRY_STATUS (entry) = GST_CLOCK_EARLY;

  if (entry->func != NULL) {
    GST_OBJECT_UNLOCK (test_clock);
    entry->func (GST_CLOCK (test_clock), priv->internal_time, entry,
        entry->user_data);
    GST_OBJECT_LOCK (test_clock);
  }

  gst_test_clock_remove_entry (test_clock, entry);

  if (GST_CLOCK_ENTRY_TYPE (entry) == GST_CLOCK_ENTRY_PERIODIC) {
    GST_CLOCK_ENTRY_TIME (entry) += GST_CLOCK_ENTRY_INTERVAL (entry);

    if (entry->func != NULL)
      gst_test_clock_add_entry (test_clock, entry, NULL);
  }
}
Ejemplo n.º 8
0
static void
gst_clock_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstClock *clock;
  GstClockPrivate *priv;

  clock = GST_CLOCK (object);
  priv = clock->priv;

  switch (prop_id) {
    case PROP_WINDOW_SIZE:
      GST_CLOCK_SLAVE_LOCK (clock);
      priv->window_size = g_value_get_int (value);
      priv->window_threshold = MIN (priv->window_threshold, priv->window_size);
      priv->times = g_renew (GstClockTime, priv->times, 4 * priv->window_size);
      /* restart calibration */
      priv->filling = TRUE;
      priv->time_index = 0;
      GST_CLOCK_SLAVE_UNLOCK (clock);
      break;
    case PROP_WINDOW_THRESHOLD:
      GST_CLOCK_SLAVE_LOCK (clock);
      priv->window_threshold = MIN (g_value_get_int (value), priv->window_size);
      GST_CLOCK_SLAVE_UNLOCK (clock);
      break;
    case PROP_TIMEOUT:
      gst_clock_set_timeout (clock, g_value_get_uint64 (value));
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}
static gboolean
gst_adaptive_demux_update_test_clock (gpointer user_data)
{
  GstAdaptiveDemuxTestEnginePrivate *priv =
      (GstAdaptiveDemuxTestEnginePrivate *) user_data;
  GstClockID id;
  GstClockTime next_entry;
  GstTestClock *clock = GST_TEST_CLOCK (priv->engine.clock);

  fail_unless (clock != NULL);
  next_entry = gst_test_clock_get_next_entry_time (clock);
  if (next_entry != GST_CLOCK_TIME_NONE) {
    /* tests that do not want the manifest to update will set the update period
     * to a big value, eg 500s. The manifest update task will register an alarm
     * for that value.
     * We do not want the clock to jump to that. If it does, the manifest update
     * task will keep scheduling and use all the cpu power, starving the other
     * threads.
     * Usually the test require the clock to update with approx 3s, so we will
     * allow only updates smaller than 100s
     */
    GstClockTime curr_time = gst_clock_get_time (GST_CLOCK (clock));
    if (next_entry - curr_time < 100 * GST_SECOND) {
      gst_test_clock_set_time (clock, next_entry);
      id = gst_test_clock_process_next_clock_id (clock);
      fail_unless (id != NULL);
      gst_clock_id_unref (id);
    }
  }
  return TRUE;
}
static void
gst_net_client_clock_constructed (GObject * object)
{
  GstNetClientClock *self = GST_NET_CLIENT_CLOCK (object);
  GstClock *internal_clock;
  GList *l;
  ClockCache *cache = NULL;

  G_OBJECT_CLASS (gst_net_client_clock_parent_class)->constructed (object);

  G_LOCK (clocks_lock);
  for (l = clocks; l; l = l->next) {
    ClockCache *tmp = l->data;
    GstNetClientInternalClock *internal_clock =
        GST_NET_CLIENT_INTERNAL_CLOCK (tmp->clock);

    if (strcmp (internal_clock->address, self->priv->address) == 0 &&
        internal_clock->port == self->priv->port) {
      cache = tmp;

      if (cache->remove_id) {
        gst_clock_id_unschedule (cache->remove_id);
        cache->remove_id = NULL;
      }
      break;
    }
  }

  if (!cache) {
    cache = g_new0 (ClockCache, 1);

    cache->clock =
        g_object_new (GST_TYPE_NET_CLIENT_INTERNAL_CLOCK, "address",
        self->priv->address, "port", self->priv->port, "is-ntp",
        self->priv->is_ntp, NULL);
    clocks = g_list_prepend (clocks, cache);

    /* Not actually leaked but is cached for a while before being disposed,
     * see gst_net_client_clock_finalize, so pretend it is to not confuse
     * tests. */
    GST_OBJECT_FLAG_SET (cache->clock, GST_OBJECT_FLAG_MAY_BE_LEAKED);
  }

  cache->clocks = g_list_prepend (cache->clocks, self);

  GST_OBJECT_LOCK (cache->clock);
  if (gst_clock_is_synced (cache->clock))
    gst_clock_set_synced (GST_CLOCK (self), TRUE);
  self->priv->synced_id =
      g_signal_connect (cache->clock, "synced",
      G_CALLBACK (gst_net_client_clock_synced_cb), self);
  GST_OBJECT_UNLOCK (cache->clock);

  G_UNLOCK (clocks_lock);

  self->priv->internal_clock = internal_clock = cache->clock;

  /* all systems go, cap'n */
}
Ejemplo n.º 11
0
static gint
gst_net_client_clock_do_select (GstNetClientClock * self)
{
  while (TRUE) {
    GstClockTime diff;
    gint ret;

    GST_LOG_OBJECT (self, "doing select");

    diff = gst_clock_get_internal_time (GST_CLOCK (self));
    ret = gst_poll_wait (self->priv->fdset, self->current_timeout);
    diff = gst_clock_get_internal_time (GST_CLOCK (self)) - diff;

    if (diff > self->current_timeout)
      self->current_timeout = 0;
    else
      self->current_timeout -= diff;

    GST_LOG_OBJECT (self, "select returned %d", ret);

    if (ret < 0 && errno != EBUSY) {
      if (errno != EAGAIN && errno != EINTR)
        goto select_error;
      else
        continue;
    } else {
      return ret;
    }

    g_assert_not_reached ();

    /* log errors and keep going */
  select_error:
    {
      GST_WARNING_OBJECT (self, "select error %d: %s (%d)", ret,
          g_strerror (errno), errno);
      continue;
    }
  }

  g_assert_not_reached ();
  return -1;
}
Ejemplo n.º 12
0
static void
gst_uri_transcode_bin_constructed (GObject * object)
{
#if HAVE_GETRUSAGE
  GstUriTranscodeBin *self = GST_URI_TRANSCODE_BIN (object);

  self->cpu_clock =
      GST_CLOCK (gst_cpu_throttling_clock_new (self->wanted_cpu_usage));
  gst_pipeline_use_clock (GST_PIPELINE (self), self->cpu_clock);
#endif

  ((GObjectClass *) parent_class)->constructed (object);
}
Ejemplo n.º 13
0
static void
gst_clock_dispose (GObject * object)
{
  GstClock *clock = GST_CLOCK (object);
  GstClock **master_p;

  GST_OBJECT_LOCK (clock);
  master_p = &clock->master;
  gst_object_replace ((GstObject **) master_p, NULL);
  GST_OBJECT_UNLOCK (clock);

  G_OBJECT_CLASS (parent_class)->dispose (object);
}
Ejemplo n.º 14
0
int
main (void)
{
  GstClock *clock;
  int nonexistent;

  clock = GST_CLOCK (g_object_new (LP_TYPE_CLOCK, NULL));
  g_assert_nonnull (clock);
  g_object_get (clock, "nonexistent", &nonexistent, NULL);
  g_object_unref (clock);

  exit (EXIT_SUCCESS);
}
static void
gst_cpu_throttling_clock_init (GstCpuThrottlingClock * self)
{
  self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self,
      GST_TYPE_CPU_THROTTLING_CLOCK, GstCpuThrottlingClockPrivate);

  self->priv->current_wait_time = GST_MSECOND;
  self->priv->wanted_cpu_usage = 100;
  self->priv->timer = gst_poll_new_timer ();
  self->priv->time_between_evals = GST_SECOND / 4;
  self->priv->sclock = GST_CLOCK (gst_system_clock_obtain ());


  getrusage (RUSAGE_SELF, &self->priv->last_usage);
}
Ejemplo n.º 16
0
static void
gst_clock_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstClock *clock;

  clock = GST_CLOCK (object);

  switch (prop_id) {
    case PROP_STATS:
      GST_OBJECT_LOCK (clock);
      clock->stats = g_value_get_boolean (value);
      GST_OBJECT_UNLOCK (clock);
      g_object_notify (object, "stats");
      break;
    case PROP_WINDOW_SIZE:
      GST_CLOCK_SLAVE_LOCK (clock);
      clock->window_size = g_value_get_int (value);
      clock->window_threshold =
          MIN (clock->window_threshold, clock->window_size);
      clock->times =
          g_renew (GstClockTime, clock->times, 4 * clock->window_size);
      /* restart calibration */
      clock->filling = TRUE;
      clock->time_index = 0;
      GST_CLOCK_SLAVE_UNLOCK (clock);
      break;
    case PROP_WINDOW_THRESHOLD:
      GST_CLOCK_SLAVE_LOCK (clock);
      clock->window_threshold =
          MIN (g_value_get_int (value), clock->window_size);
      GST_CLOCK_SLAVE_UNLOCK (clock);
      break;
    case PROP_TIMEOUT:
      GST_CLOCK_SLAVE_LOCK (clock);
      clock->timeout = g_value_get_uint64 (value);
      GST_CLOCK_SLAVE_UNLOCK (clock);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}
Ejemplo n.º 17
0
static void
gst_clock_finalize (GObject * object)
{
  GstClock *clock = GST_CLOCK (object);

  GST_CLOCK_SLAVE_LOCK (clock);
  if (clock->priv->clockid) {
    gst_clock_id_unschedule (clock->priv->clockid);
    gst_clock_id_unref (clock->priv->clockid);
    clock->priv->clockid = NULL;
  }
  g_free (clock->priv->times);
  clock->priv->times = NULL;
  GST_CLOCK_SLAVE_UNLOCK (clock);

  g_mutex_clear (&clock->priv->slave_lock);

  G_OBJECT_CLASS (parent_class)->finalize (object);
}
gint
main (gint argc, gchar ** argv)
{
  GOptionContext *opt_ctx;
  GstClock *clock;
  GError *err = NULL;

  opt_ctx = g_option_context_new ("- GStreamer PTP clock test app");
  g_option_context_add_main_entries (opt_ctx, opt_entries, NULL);
  g_option_context_add_group (opt_ctx, gst_init_get_option_group ());
  if (!g_option_context_parse (opt_ctx, &argc, &argv, &err))
    g_error ("Error parsing options: %s", err->message);
  g_clear_error (&err);
  g_option_context_free (opt_ctx);

  if (!gst_ptp_init (GST_PTP_CLOCK_ID_NONE, NULL))
    g_error ("failed to init ptp");

  if (stats)
    gst_ptp_statistics_callback_add (stats_cb, NULL, NULL);

  clock = gst_ptp_clock_new ("test-clock", domain);

  gst_clock_wait_for_sync (GST_CLOCK (clock), GST_CLOCK_TIME_NONE);

  while (TRUE) {
    GstClockTime local, remote;
    GstClockTimeDiff diff;

    local = g_get_real_time () * 1000;
    remote = gst_clock_get_time (clock);
    diff = GST_CLOCK_DIFF (local, remote);

    g_print ("local: %" GST_TIME_FORMAT " ptp: %" GST_TIME_FORMAT " diff: %s%"
        GST_TIME_FORMAT "\n", GST_TIME_ARGS (local), GST_TIME_ARGS (remote),
        (diff < 0 ? "-" : " "), GST_TIME_ARGS (ABS (diff)));
    g_usleep (100000);
  }

  return 0;
}
static void
gst_net_client_internal_clock_init (GstNetClientInternalClock * self)
{
  GST_OBJECT_FLAG_SET (self, GST_CLOCK_FLAG_NEEDS_STARTUP_SYNC);

  self->port = DEFAULT_PORT;
  self->address = g_strdup (DEFAULT_ADDRESS);
  self->is_ntp = FALSE;

  gst_clock_set_timeout (GST_CLOCK (self), DEFAULT_TIMEOUT);

  self->thread = NULL;

  self->servaddr = NULL;
  self->rtt_avg = GST_CLOCK_TIME_NONE;
  self->roundtrip_limit = DEFAULT_ROUNDTRIP_LIMIT;
  self->minimum_update_interval = DEFAULT_MINIMUM_UPDATE_INTERVAL;
  self->last_remote_poll_interval = GST_CLOCK_TIME_NONE;
  self->skipped_updates = 0;
  self->last_rtts_missing = MEDIAN_PRE_FILTERING_WINDOW;
}
static void
gst_test_clock_add_entry (GstTestClock * test_clock,
    GstClockEntry * entry, GstClockTimeDiff * jitter)
{
  GstTestClockPrivate *priv = GST_TEST_CLOCK_GET_PRIVATE (test_clock);
  GstClockTime now;
  GstClockEntryContext *ctx;

  now = gst_clock_adjust_unlocked (GST_CLOCK (test_clock), priv->internal_time);

  if (jitter != NULL)
    *jitter = GST_CLOCK_DIFF (GST_CLOCK_ENTRY_TIME (entry), now);

  ctx = g_slice_new (GstClockEntryContext);
  ctx->clock_entry = GST_CLOCK_ENTRY (gst_clock_id_ref (entry));
  ctx->time_diff = GST_CLOCK_DIFF (now, GST_CLOCK_ENTRY_TIME (entry));

  priv->entry_contexts = g_list_insert_sorted (priv->entry_contexts, ctx,
      gst_clock_entry_context_compare_func);

  g_cond_broadcast (&priv->entry_added_cond);
}
Ejemplo n.º 21
0
static void
gst_net_client_clock_observe_times (GstNetClientClock * self,
    GstClockTime local_1, GstClockTime remote, GstClockTime local_2)
{
  GstClockTime current_timeout;
  GstClockTime local_avg;
  gdouble r_squared;
  GstClock *clock;

  if (local_2 < local_1)
    goto bogus_observation;

  local_avg = (local_2 + local_1) / 2;

  clock = GST_CLOCK_CAST (self);

  if (gst_clock_add_observation (GST_CLOCK (self), local_avg, remote,
          &r_squared)) {
    /* geto formula */
    current_timeout = (1e-3 / (1 - MIN (r_squared, 0.99999))) * GST_SECOND;
    current_timeout = MIN (current_timeout, gst_clock_get_timeout (clock));
  } else {
    current_timeout = 0;
  }

  GST_INFO ("next timeout: %" GST_TIME_FORMAT, GST_TIME_ARGS (current_timeout));
  self->priv->timeout_expiration = gst_util_get_timestamp () + current_timeout;

  return;

bogus_observation:
  {
    GST_WARNING_OBJECT (self, "time packet receive time < send time (%"
        GST_TIME_FORMAT " < %" GST_TIME_FORMAT ")", GST_TIME_ARGS (local_1),
        GST_TIME_ARGS (local_2));
    return;
  }
}
Ejemplo n.º 22
0
static void
gst_net_client_clock_observe_times (GstNetClientClock * self,
    GstClockTime local_1, GstClockTime remote, GstClockTime local_2)
{
  GstClockTime local_avg;
  gdouble r_squared;
  GstClock *clock;

  if (local_2 < local_1)
    goto bogus_observation;

  local_avg = (local_2 + local_1) / 2;

  clock = GST_CLOCK_CAST (self);

  gst_clock_add_observation (GST_CLOCK (self), local_avg, remote, &r_squared);

  GST_CLOCK_SLAVE_LOCK (self);
  if (clock->filling) {
    self->current_timeout = 0;
  } else {
    /* geto formula */
    self->current_timeout =
        (1e-3 / (1 - MIN (r_squared, 0.99999))) * GST_SECOND;
    self->current_timeout = MIN (self->current_timeout, clock->timeout);
  }
  GST_CLOCK_SLAVE_UNLOCK (clock);

  return;

bogus_observation:
  {
    GST_WARNING_OBJECT (self, "time packet receive time < send time (%"
        GST_TIME_FORMAT " < %" GST_TIME_FORMAT ")", GST_TIME_ARGS (local_1),
        GST_TIME_ARGS (local_2));
    return;
  }
}
Ejemplo n.º 23
0
static GstClock *
gst_wasapi_src_provide_clock (GstElement * element)
{
  GstWasapiSrc *self = GST_WASAPI_SRC (element);
  GstClock *clock;

  GST_OBJECT_LOCK (self);

  if (self->client_clock == NULL)
    goto wrong_state;

  clock = GST_CLOCK (gst_object_ref (self->clock));

  GST_OBJECT_UNLOCK (self);
  return clock;

  /* ERRORS */
wrong_state:
  {
    GST_OBJECT_UNLOCK (self);
    GST_DEBUG_OBJECT (self, "IAudioClock not acquired");
    return NULL;
  }
}
static void
gst_net_client_internal_clock_observe_times (GstNetClientInternalClock * self,
    GstClockTime local_1, GstClockTime remote_1, GstClockTime remote_2,
    GstClockTime local_2)
{
  GstClockTime current_timeout = 0;
  GstClockTime local_avg, remote_avg;
  gdouble r_squared;
  GstClock *clock;
  GstClockTime rtt, rtt_limit, min_update_interval;
  /* Use for discont tracking */
  GstClockTime time_before = 0;
  GstClockTime min_guess = 0;
  GstClockTimeDiff time_discont = 0;
  gboolean synched, now_synched;
  GstClockTime internal_time, external_time, rate_num, rate_den;
  GstClockTime orig_internal_time, orig_external_time, orig_rate_num,
      orig_rate_den;
  GstClockTime max_discont;
  GstClockTime last_rtts[MEDIAN_PRE_FILTERING_WINDOW];
  GstClockTime median;
  gint i;

  GST_OBJECT_LOCK (self);
  rtt_limit = self->roundtrip_limit;

  GST_LOG_OBJECT (self,
      "local1 %" G_GUINT64_FORMAT " remote1 %" G_GUINT64_FORMAT " remote2 %"
      G_GUINT64_FORMAT " local2 %" G_GUINT64_FORMAT, local_1, remote_1,
      remote_2, local_2);

  /* If the server told us a poll interval and it's bigger than the
   * one configured via the property, use the server's */
  if (self->last_remote_poll_interval != GST_CLOCK_TIME_NONE &&
      self->last_remote_poll_interval > self->minimum_update_interval)
    min_update_interval = self->last_remote_poll_interval;
  else
    min_update_interval = self->minimum_update_interval;
  GST_OBJECT_UNLOCK (self);

  if (local_2 < local_1) {
    GST_LOG_OBJECT (self, "Dropping observation: receive time %" GST_TIME_FORMAT
        " < send time %" GST_TIME_FORMAT, GST_TIME_ARGS (local_1),
        GST_TIME_ARGS (local_2));
    goto bogus_observation;
  }

  if (remote_2 < remote_1) {
    GST_LOG_OBJECT (self,
        "Dropping observation: remote receive time %" GST_TIME_FORMAT
        " < send time %" GST_TIME_FORMAT, GST_TIME_ARGS (remote_1),
        GST_TIME_ARGS (remote_2));
    goto bogus_observation;
  }

  /* The round trip time is (assuming symmetric path delays)
   * delta = (local_2 - local_1) - (remote_2 - remote_1)
   */

  rtt = GST_CLOCK_DIFF (local_1, local_2) - GST_CLOCK_DIFF (remote_1, remote_2);

  if ((rtt_limit > 0) && (rtt > rtt_limit)) {
    GST_LOG_OBJECT (self,
        "Dropping observation: RTT %" GST_TIME_FORMAT " > limit %"
        GST_TIME_FORMAT, GST_TIME_ARGS (rtt), GST_TIME_ARGS (rtt_limit));
    goto bogus_observation;
  }

  for (i = 1; i < MEDIAN_PRE_FILTERING_WINDOW; i++)
    self->last_rtts[i - 1] = self->last_rtts[i];
  self->last_rtts[i - 1] = rtt;

  if (self->last_rtts_missing) {
    self->last_rtts_missing--;
  } else {
    memcpy (&last_rtts, &self->last_rtts, sizeof (last_rtts));
    g_qsort_with_data (&last_rtts,
        MEDIAN_PRE_FILTERING_WINDOW, sizeof (GstClockTime),
        (GCompareDataFunc) compare_clock_time, NULL);

    median = last_rtts[MEDIAN_PRE_FILTERING_WINDOW / 2];

    /* FIXME: We might want to use something else here, like only allowing
     * things in the interquartile range, or also filtering away delays that
     * are too small compared to the median. This here worked well enough
     * in tests so far.
     */
    if (rtt > 2 * median) {
      GST_LOG_OBJECT (self,
          "Dropping observation, long RTT %" GST_TIME_FORMAT " > 2 * median %"
          GST_TIME_FORMAT, GST_TIME_ARGS (rtt), GST_TIME_ARGS (median));
      goto bogus_observation;
    }
  }

  /* Track an average round trip time, for a bit of smoothing */
  /* Always update before discarding a sample, so genuine changes in
   * the network get picked up, eventually */
  if (self->rtt_avg == GST_CLOCK_TIME_NONE)
    self->rtt_avg = rtt;
  else if (rtt < self->rtt_avg) /* Shorter RTTs carry more weight than longer */
    self->rtt_avg = (3 * self->rtt_avg + rtt) / 4;
  else
    self->rtt_avg = (15 * self->rtt_avg + rtt) / 16;

  if (rtt > 2 * self->rtt_avg) {
    GST_LOG_OBJECT (self,
        "Dropping observation, long RTT %" GST_TIME_FORMAT " > 2 * avg %"
        GST_TIME_FORMAT, GST_TIME_ARGS (rtt), GST_TIME_ARGS (self->rtt_avg));
    goto bogus_observation;
  }

  /* The difference between the local and remote clock (again assuming
   * symmetric path delays):
   *
   * local_1 + delta / 2 - remote_1 = theta
   * or
   * local_2 - delta / 2 - remote_2 = theta
   *
   * which gives after some simple algebraic transformations:
   *
   *         (remote_1 - local_1) + (remote_2 - local_2)
   * theta = -------------------------------------------
   *                              2
   *
   *
   * Thus remote time at local_avg is equal to:
   *
   * local_avg + theta =
   *
   * local_1 + local_2   (remote_1 - local_1) + (remote_2 - local_2)
   * ----------------- + -------------------------------------------
   *         2                                2
   *
   * =
   *
   * remote_1 + remote_2
   * ------------------- = remote_avg
   *          2
   *
   * We use this for our clock estimation, i.e. local_avg at remote clock
   * being the same as remote_avg.
   */

  local_avg = (local_2 + local_1) / 2;
  remote_avg = (remote_2 + remote_1) / 2;

  GST_LOG_OBJECT (self,
      "remoteavg %" G_GUINT64_FORMAT " localavg %" G_GUINT64_FORMAT,
      remote_avg, local_avg);

  clock = GST_CLOCK_CAST (self);

  /* Store what the clock produced as 'now' before this update */
  gst_clock_get_calibration (GST_CLOCK_CAST (self), &orig_internal_time,
      &orig_external_time, &orig_rate_num, &orig_rate_den);
  internal_time = orig_internal_time;
  external_time = orig_external_time;
  rate_num = orig_rate_num;
  rate_den = orig_rate_den;

  min_guess =
      gst_clock_adjust_with_calibration (GST_CLOCK_CAST (self), local_1,
      internal_time, external_time, rate_num, rate_den);
  time_before =
      gst_clock_adjust_with_calibration (GST_CLOCK_CAST (self), local_2,
      internal_time, external_time, rate_num, rate_den);

  /* Maximum discontinuity, when we're synched with the master. Could make this a property,
   * but this value seems to work fine */
  max_discont = self->rtt_avg / 4;

  /* If the remote observation was within a max_discont window around our min/max estimates, we're synched */
  synched =
      (GST_CLOCK_DIFF (remote_avg, min_guess) < (GstClockTimeDiff) (max_discont)
      && GST_CLOCK_DIFF (time_before,
          remote_avg) < (GstClockTimeDiff) (max_discont));

  if (gst_clock_add_observation_unapplied (GST_CLOCK_CAST (self),
          local_avg, remote_avg, &r_squared, &internal_time, &external_time,
          &rate_num, &rate_den)) {

    /* Now compare the difference (discont) in the clock
     * after this observation */
    time_discont = GST_CLOCK_DIFF (time_before,
        gst_clock_adjust_with_calibration (GST_CLOCK_CAST (self), local_2,
            internal_time, external_time, rate_num, rate_den));

    /* If we were in sync with the remote clock, clamp the allowed
     * discontinuity to within quarter of one RTT. In sync means our send/receive estimates
     * of remote time correctly windowed the actual remote time observation */
    if (synched && ABS (time_discont) > max_discont) {
      GstClockTimeDiff offset;
      GST_DEBUG_OBJECT (clock,
          "Too large a discont, clamping to 1/4 average RTT = %"
          GST_TIME_FORMAT, GST_TIME_ARGS (max_discont));
      if (time_discont > 0) {   /* Too large a forward step - add a -ve offset */
        offset = max_discont - time_discont;
        if (-offset > external_time)
          external_time = 0;
        else
          external_time += offset;
      } else {                  /* Too large a backward step - add a +ve offset */
        offset = -(max_discont + time_discont);
        external_time += offset;
      }

      time_discont += offset;
    }

    /* Check if the new clock params would have made our observation within range */
    now_synched =
        (GST_CLOCK_DIFF (remote_avg,
            gst_clock_adjust_with_calibration (GST_CLOCK_CAST (self),
                local_1, internal_time, external_time, rate_num,
                rate_den)) < (GstClockTimeDiff) (max_discont))
        &&
        (GST_CLOCK_DIFF (gst_clock_adjust_with_calibration
            (GST_CLOCK_CAST (self), local_2, internal_time, external_time,
                rate_num, rate_den),
            remote_avg) < (GstClockTimeDiff) (max_discont));

    /* Only update the clock if we had synch or just gained it */
    if (synched || now_synched || self->skipped_updates > MAX_SKIPPED_UPDATES) {
      gst_clock_set_calibration (GST_CLOCK_CAST (self), internal_time,
          external_time, rate_num, rate_den);
      /* ghetto formula - shorter timeout for bad correlations */
      current_timeout = (1e-3 / (1 - MIN (r_squared, 0.99999))) * GST_SECOND;
      current_timeout =
          MIN (current_timeout, gst_clock_get_timeout (GST_CLOCK_CAST (self)));
      self->skipped_updates = 0;

      /* FIXME: When do we consider the clock absolutely not synced anymore? */
      gst_clock_set_synced (GST_CLOCK (self), TRUE);
    } else {
      /* Restore original calibration vars for the report, we're not changing the clock */
      internal_time = orig_internal_time;
      external_time = orig_external_time;
      rate_num = orig_rate_num;
      rate_den = orig_rate_den;
      time_discont = 0;
      self->skipped_updates++;
    }
  }

  /* Limit the polling to at most one per minimum_update_interval */
  if (rtt < min_update_interval)
    current_timeout = MAX (min_update_interval - rtt, current_timeout);

  GST_OBJECT_LOCK (self);
  if (self->busses) {
    GstStructure *s;
    GstMessage *msg;
    GList *l;

    /* Output a stats message, whether we updated the clock or not */
    s = gst_structure_new ("gst-netclock-statistics",
        "synchronised", G_TYPE_BOOLEAN, synched,
        "rtt", G_TYPE_UINT64, rtt,
        "rtt-average", G_TYPE_UINT64, self->rtt_avg,
        "local", G_TYPE_UINT64, local_avg,
        "remote", G_TYPE_UINT64, remote_avg,
        "discontinuity", G_TYPE_INT64, time_discont,
        "remote-min-estimate", G_TYPE_UINT64, min_guess,
        "remote-max-estimate", G_TYPE_UINT64, time_before,
        "remote-min-error", G_TYPE_INT64, GST_CLOCK_DIFF (remote_avg,
            min_guess), "remote-max-error", G_TYPE_INT64,
        GST_CLOCK_DIFF (remote_avg, time_before), "request-send", G_TYPE_UINT64,
        local_1, "request-receive", G_TYPE_UINT64, local_2, "r-squared",
        G_TYPE_DOUBLE, r_squared, "timeout", G_TYPE_UINT64, current_timeout,
        "internal-time", G_TYPE_UINT64, internal_time, "external-time",
        G_TYPE_UINT64, external_time, "rate-num", G_TYPE_UINT64, rate_num,
        "rate-den", G_TYPE_UINT64, rate_den, "rate", G_TYPE_DOUBLE,
        (gdouble) (rate_num) / rate_den, "local-clock-offset", G_TYPE_INT64,
        GST_CLOCK_DIFF (internal_time, external_time), NULL);
    msg = gst_message_new_element (GST_OBJECT (self), s);

    for (l = self->busses; l; l = l->next)
      gst_bus_post (l->data, gst_message_ref (msg));
    gst_message_unref (msg);
  }
  GST_OBJECT_UNLOCK (self);

  GST_INFO ("next timeout: %" GST_TIME_FORMAT, GST_TIME_ARGS (current_timeout));
  self->timeout_expiration = gst_util_get_timestamp () + current_timeout;

  return;

bogus_observation:
  /* Schedule a new packet again soon */
  self->timeout_expiration = gst_util_get_timestamp () + (GST_SECOND / 4);
  return;
}
Ejemplo n.º 25
0
static gpointer
gst_net_client_clock_thread (gpointer data)
{
  GstNetClientClock *self = data;
  GstNetTimePacket *packet;
  GSocket *socket = self->priv->socket;
  GError *err = NULL;
  GstClock *clock = data;

  GST_INFO_OBJECT (self, "net client clock thread running, socket=%p", socket);

  g_socket_set_blocking (socket, TRUE);
  g_socket_set_timeout (socket, 0);

  while (!g_cancellable_is_cancelled (self->priv->cancel)) {
    GstClockTime expiration_time = self->priv->timeout_expiration;
    GstClockTime now = gst_util_get_timestamp ();
    gint64 socket_timeout;

    if (now >= expiration_time || (expiration_time - now) <= GST_MSECOND) {
      socket_timeout = 0;
    } else {
      socket_timeout = (expiration_time - now) / GST_USECOND;
    }

    GST_TRACE_OBJECT (self, "timeout: %" G_GINT64_FORMAT "us", socket_timeout);

    if (!g_socket_condition_timed_wait (socket, G_IO_IN, socket_timeout,
            self->priv->cancel, &err)) {
      /* cancelled, timeout or error */
      if (err->code == G_IO_ERROR_CANCELLED) {
        GST_INFO_OBJECT (self, "cancelled");
        g_clear_error (&err);
        break;
      } else if (err->code == G_IO_ERROR_TIMED_OUT) {
        /* timed out, let's send another packet */
        GST_DEBUG_OBJECT (self, "timed out");

        packet = gst_net_time_packet_new (NULL);

        packet->local_time = gst_clock_get_internal_time (GST_CLOCK (self));

        GST_DEBUG_OBJECT (self,
            "sending packet, local time = %" GST_TIME_FORMAT,
            GST_TIME_ARGS (packet->local_time));

        gst_net_time_packet_send (packet, self->priv->socket,
            self->priv->servaddr, NULL);

        g_free (packet);

        /* reset timeout (but are expecting a response sooner anyway) */
        self->priv->timeout_expiration =
            gst_util_get_timestamp () + gst_clock_get_timeout (clock);
      } else {
        GST_DEBUG_OBJECT (self, "socket error: %s", err->message);
        g_usleep (G_USEC_PER_SEC / 10); /* throttle */
      }
      g_clear_error (&err);
    } else {
      GstClockTime new_local;

      /* got packet */

      new_local = gst_clock_get_internal_time (GST_CLOCK (self));

      packet = gst_net_time_packet_receive (socket, NULL, &err);

      if (packet != NULL) {
        GST_LOG_OBJECT (self, "got packet back");
        GST_LOG_OBJECT (self, "local_1 = %" GST_TIME_FORMAT,
            GST_TIME_ARGS (packet->local_time));
        GST_LOG_OBJECT (self, "remote = %" GST_TIME_FORMAT,
            GST_TIME_ARGS (packet->remote_time));
        GST_LOG_OBJECT (self, "local_2 = %" GST_TIME_FORMAT,
            GST_TIME_ARGS (new_local));

        /* observe_times will reset the timeout */
        gst_net_client_clock_observe_times (self, packet->local_time,
            packet->remote_time, new_local);

        g_free (packet);
      } else if (err != NULL) {
        GST_WARNING_OBJECT (self, "receive error: %s", err->message);
        g_clear_error (&err);
      }
    }
  }

  GST_INFO_OBJECT (self, "shutting down net client clock thread");
  return NULL;
}
Ejemplo n.º 26
0
static gpointer
gst_net_client_clock_thread (gpointer data)
{
  GstNetClientClock *self = data;
  struct sockaddr_in tmpaddr;
  socklen_t len;
  GstNetTimePacket *packet;
  gint ret;
  GstClock *clock = data;

  while (TRUE) {
    ret = gst_net_client_clock_do_select (self);

    if (ret < 0 && errno == EBUSY) {
      GST_LOG_OBJECT (self, "stop");
      goto stopped;
    } else if (ret == 0) {
      /* timed out, let's send another packet */
      GST_DEBUG_OBJECT (self, "timed out");

      packet = gst_net_time_packet_new (NULL);

      packet->local_time = gst_clock_get_internal_time (GST_CLOCK (self));

      GST_DEBUG_OBJECT (self, "sending packet, local time = %" GST_TIME_FORMAT,
          GST_TIME_ARGS (packet->local_time));
      gst_net_time_packet_send (packet, self->priv->sock.fd,
          (struct sockaddr *) self->servaddr, sizeof (struct sockaddr_in));

      g_free (packet);

      /* reset timeout */
      self->current_timeout = clock->timeout;
      continue;
    } else if (gst_poll_fd_can_read (self->priv->fdset, &self->priv->sock)) {
      /* got data in */
      GstClockTime new_local = gst_clock_get_internal_time (GST_CLOCK (self));

      len = sizeof (struct sockaddr);
      packet = gst_net_time_packet_receive (self->priv->sock.fd,
          (struct sockaddr *) &tmpaddr, &len);

      if (!packet)
        goto receive_error;

      GST_LOG_OBJECT (self, "got packet back");
      GST_LOG_OBJECT (self, "local_1 = %" GST_TIME_FORMAT,
          GST_TIME_ARGS (packet->local_time));
      GST_LOG_OBJECT (self, "remote = %" GST_TIME_FORMAT,
          GST_TIME_ARGS (packet->remote_time));
      GST_LOG_OBJECT (self, "local_2 = %" GST_TIME_FORMAT,
          GST_TIME_ARGS (new_local));

      /* observe_times will reset the timeout */
      gst_net_client_clock_observe_times (self, packet->local_time,
          packet->remote_time, new_local);

      g_free (packet);
      continue;
    } else {
      GST_WARNING_OBJECT (self, "unhandled select return state?");
      continue;
    }

    g_assert_not_reached ();

  stopped:
    {
      GST_DEBUG_OBJECT (self, "shutting down");
      /* socket gets closed in _stop() */
      return NULL;
    }
  receive_error:
    {
      GST_WARNING_OBJECT (self, "receive error");
      continue;
    }

    g_assert_not_reached ();

  }

  g_assert_not_reached ();

  return NULL;
}
Ejemplo n.º 27
0
static gpointer
gst_net_client_clock_thread (gpointer data)
{
  GstNetClientClock *self = data;
  GstNetTimePacket *packet;
  GMainContext *ctx;
  GSourceFuncs funcs = { NULL, };
  GSource *source;
  GIOCondition cond;
  gboolean timeout;
  GSocket *socket = self->priv->socket;
  GError *err = NULL;
  GstClock *clock = data;

  GST_INFO_OBJECT (self, "net client clock thread running, socket=%p", socket);

  g_socket_set_blocking (socket, TRUE);
  g_socket_set_timeout (socket, 0);

  ctx = g_main_context_new ();

  source = g_socket_create_source (socket, G_IO_IN, self->priv->cancel);
  g_source_set_name (source, "GStreamer net client clock thread socket");
  g_source_set_callback (source, (GSourceFunc) gst_net_client_clock_socket_cb,
      &cond, NULL);
  g_source_attach (source, ctx);
  g_source_unref (source);

  /* GSocket only support second granularity for timeouts, so roll our own
   * timeout source (so we don't have to create a new source whenever the
   * timeout changes, as we would have to do with the default timeout source) */
  funcs.prepare = gst_net_client_clock_timeout_source_prepare;
  funcs.check = gst_net_client_clock_timeout_source_check;
  funcs.dispatch = gst_net_client_clock_timeout_source_dispatch;
  funcs.finalize = NULL;
  source = g_source_new (&funcs, sizeof (GstNetClientClockTimeoutSource));
  ((GstNetClientClockTimeoutSource *) source)->clock = self;
  ((GstNetClientClockTimeoutSource *) source)->p_timeout = &timeout;
  g_source_set_name (source, "GStreamer net client clock timeout");
  g_source_attach (source, ctx);
  g_source_unref (source);

  while (!g_cancellable_is_cancelled (self->priv->cancel)) {
    cond = 0;
    timeout = FALSE;
    g_main_context_iteration (ctx, TRUE);

    if (g_cancellable_is_cancelled (self->priv->cancel))
      break;

    if (timeout) {
      /* timed out, let's send another packet */
      GST_DEBUG_OBJECT (self, "timed out");

      packet = gst_net_time_packet_new (NULL);

      packet->local_time = gst_clock_get_internal_time (GST_CLOCK (self));

      GST_DEBUG_OBJECT (self, "sending packet, local time = %" GST_TIME_FORMAT,
          GST_TIME_ARGS (packet->local_time));

      gst_net_time_packet_send (packet, self->priv->socket,
          self->priv->servaddr, NULL);

      g_free (packet);

      /* reset timeout (but are expecting a response sooner anyway) */
      self->priv->timeout_expiration =
          gst_util_get_timestamp () + gst_clock_get_timeout (clock);
      continue;
    }

    /* got data to read? */
    if ((cond & G_IO_IN)) {
      GstClockTime new_local;

      new_local = gst_clock_get_internal_time (GST_CLOCK (self));

      packet = gst_net_time_packet_receive (socket, NULL, &err);

      if (err != NULL) {
        GST_WARNING_OBJECT (self, "receive error: %s", err->message);
        g_error_free (err);
        err = NULL;
        continue;
      }

      GST_LOG_OBJECT (self, "got packet back");
      GST_LOG_OBJECT (self, "local_1 = %" GST_TIME_FORMAT,
          GST_TIME_ARGS (packet->local_time));
      GST_LOG_OBJECT (self, "remote = %" GST_TIME_FORMAT,
          GST_TIME_ARGS (packet->remote_time));
      GST_LOG_OBJECT (self, "local_2 = %" GST_TIME_FORMAT,
          GST_TIME_ARGS (new_local));

      /* observe_times will reset the timeout */
      gst_net_client_clock_observe_times (self, packet->local_time,
          packet->remote_time, new_local);

      g_free (packet);
      continue;
    }

    if ((cond & (G_IO_ERR | G_IO_HUP))) {
      GST_DEBUG_OBJECT (self, "socket error?! %s", g_strerror (errno));
      g_usleep (G_USEC_PER_SEC / 10);
      continue;
    }
  }

  GST_INFO_OBJECT (self, "shutting down net client clock thread");
  g_main_context_unref (ctx);
  return NULL;
}
Ejemplo n.º 28
0
static void
gst_net_client_clock_constructed (GObject * object)
{
  GstNetClientClock *self = GST_NET_CLIENT_CLOCK (object);
  GstClock *internal_clock;
  GstClockTime internal;
  GList *l;
  ClockCache *cache = NULL;

  G_OBJECT_CLASS (gst_net_client_clock_parent_class)->constructed (object);

  G_LOCK (clocks_lock);
  for (l = clocks; l; l = l->next) {
    ClockCache *tmp = l->data;
    GstNetClientInternalClock *internal_clock =
        GST_NET_CLIENT_INTERNAL_CLOCK (tmp->clock);

    if (strcmp (internal_clock->address, self->priv->address) == 0 &&
        internal_clock->port == self->priv->port) {
      cache = tmp;

      if (cache->remove_id) {
        gst_clock_id_unschedule (cache->remove_id);
        cache->remove_id = NULL;
      }
      break;
    }
  }

  if (!cache) {
    cache = g_new0 (ClockCache, 1);

    cache->clock =
        g_object_new (GST_TYPE_NET_CLIENT_INTERNAL_CLOCK, "address",
        self->priv->address, "port", self->priv->port, "is-ntp",
        self->priv->is_ntp, NULL);
    clocks = g_list_prepend (clocks, cache);
  }

  cache->clocks = g_list_prepend (cache->clocks, self);

  GST_OBJECT_LOCK (cache->clock);
  if (gst_clock_is_synced (cache->clock))
    gst_clock_set_synced (GST_CLOCK (self), TRUE);
  self->priv->synced_id =
      g_signal_connect (cache->clock, "synced",
      G_CALLBACK (gst_net_client_clock_synced_cb), self);
  GST_OBJECT_UNLOCK (cache->clock);

  G_UNLOCK (clocks_lock);

  self->priv->internal_clock = internal_clock = cache->clock;

  /* gst_clock_get_time() values are guaranteed to be increasing. because no one
   * has called get_time on this clock yet we are free to adjust to any value
   * without worrying about worrying about MAX() issues with the clock's
   * internal time.
   */

  /* update our internal time so get_time() give something around base_time.
     assume that the rate is 1 in the beginning. */
  internal = gst_clock_get_internal_time (internal_clock);
  gst_clock_set_calibration (internal_clock, internal,
      self->priv->base_time, 1, 1);

  {
    GstClockTime now = gst_clock_get_time (internal_clock);

    if (GST_CLOCK_DIFF (now, self->priv->base_time) > 0 ||
        GST_CLOCK_DIFF (now, self->priv->base_time + GST_SECOND) < 0) {
      g_warning ("unable to set the base time, expect sync problems!");
    }
  }

  /* all systems go, cap'n */
}