Example #1
0
static VALUE
new_clock_initialize(VALUE self, VALUE src, VALUE clock)
{
    G_INITIALIZE(self, gst_message_new_new_clock(RVAL2GST_OBJ(src),
                                                 RVAL2GST_CLOCK(clock)));
    return Qnil;
}
/* MT safe */
static GstStateChangeReturn
gst_pipeline_change_state (GstElement * element, GstStateChange transition)
{
  GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
  GstPipeline *pipeline = GST_PIPELINE_CAST (element);
  GstClock *clock;

  switch (transition) {
    case GST_STATE_CHANGE_NULL_TO_READY:
      GST_OBJECT_LOCK (element);
      if (element->bus)
        gst_bus_set_flushing (element->bus, FALSE);
      GST_OBJECT_UNLOCK (element);
      break;
    case GST_STATE_CHANGE_READY_TO_PAUSED:
      GST_OBJECT_LOCK (element);
      pipeline->priv->update_clock = TRUE;
      GST_OBJECT_UNLOCK (element);

      /* READY to PAUSED starts running_time from 0 */
      reset_start_time (pipeline, 0);
      break;
    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
    {
      GstClockTime now, start_time, last_start_time, delay;
      gboolean update_clock;
      GstClock *cur_clock;

      GST_DEBUG_OBJECT (element, "selecting clock and base_time");

      GST_OBJECT_LOCK (element);
      cur_clock = element->clock;
      if (cur_clock)
        gst_object_ref (cur_clock);
      /* get the desired running_time of the first buffer aka the start_time */
      start_time = GST_ELEMENT_START_TIME (pipeline);
      last_start_time = pipeline->priv->last_start_time;
      pipeline->priv->last_start_time = start_time;
      /* see if we need to update the clock */
      update_clock = pipeline->priv->update_clock;
      pipeline->priv->update_clock = FALSE;
      delay = pipeline->delay;
      GST_OBJECT_UNLOCK (element);

      /* running time changed, either with a PAUSED or a flush, we need to check
       * if there is a new clock & update the base time */
      /* only do this for top-level, however */
      if (GST_OBJECT_PARENT (element) == NULL &&
          (update_clock || last_start_time != start_time)) {
        GST_DEBUG_OBJECT (pipeline, "Need to update start_time");

        /* when going to PLAYING, select a clock when needed. If we just got
         * flushed, we don't reselect the clock. */
        if (update_clock) {
          GST_DEBUG_OBJECT (pipeline, "Need to update clock.");
          clock = gst_element_provide_clock (element);
        } else {
          GST_DEBUG_OBJECT (pipeline,
              "Don't need to update clock, using old clock.");
          /* only try to ref if cur_clock is not NULL */
          if (cur_clock)
            gst_object_ref (cur_clock);
          clock = cur_clock;
        }

        if (clock) {
          now = gst_clock_get_time (clock);
        } else {
          GST_DEBUG_OBJECT (pipeline, "no clock, using base time of NONE");
          now = GST_CLOCK_TIME_NONE;
        }

        if (clock != cur_clock) {
          /* now distribute the clock (which could be NULL). If some
           * element refuses the clock, this will return FALSE and
           * we effectively fail the state change. */
          if (!gst_element_set_clock (element, clock))
            goto invalid_clock;

          /* if we selected and distributed a new clock, let the app
           * know about it */
          gst_element_post_message (element,
              gst_message_new_new_clock (GST_OBJECT_CAST (element), clock));
        }

        if (clock)
          gst_object_unref (clock);

        if (start_time != GST_CLOCK_TIME_NONE && now != GST_CLOCK_TIME_NONE) {
          GstClockTime new_base_time = now - start_time + delay;
          GST_DEBUG_OBJECT (element,
              "start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
              ", base_time %" GST_TIME_FORMAT,
              GST_TIME_ARGS (start_time), GST_TIME_ARGS (now),
              GST_TIME_ARGS (new_base_time));

          gst_element_set_base_time (element, new_base_time);
        } else {
          GST_DEBUG_OBJECT (pipeline,
              "NOT adjusting base_time because start_time is NONE");
        }
      } else {
        GST_DEBUG_OBJECT (pipeline,
            "NOT adjusting base_time because we selected one before");
      }

      if (cur_clock)
        gst_object_unref (cur_clock);
      break;
    }
    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
    {
      /* we take a start_time snapshot before calling the children state changes
       * so that they know about when the pipeline PAUSED. */
      pipeline_update_start_time (element);
      break;
    }
    case GST_STATE_CHANGE_PAUSED_TO_READY:
      reset_start_time (pipeline, 0);
      break;
    case GST_STATE_CHANGE_READY_TO_NULL:
      break;
  }

  result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);

  switch (transition) {
    case GST_STATE_CHANGE_NULL_TO_READY:
      break;
    case GST_STATE_CHANGE_READY_TO_PAUSED:
      break;
    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
      break;
    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
    {
      /* Take a new snapshot of the start_time after calling the state change on
       * all children. This will be the running_time of the pipeline when we go
       * back to PLAYING */
      pipeline_update_start_time (element);
      break;
    }
    case GST_STATE_CHANGE_PAUSED_TO_READY:
      break;
    case GST_STATE_CHANGE_READY_TO_NULL:
    {
      GstBus *bus;
      gboolean auto_flush;

      /* grab some stuff before we release the lock to flush out the bus */
      GST_OBJECT_LOCK (element);
      if ((bus = element->bus))
        gst_object_ref (bus);
      auto_flush = pipeline->priv->auto_flush_bus;
      GST_OBJECT_UNLOCK (element);

      if (bus) {
        if (auto_flush) {
          gst_bus_set_flushing (bus, TRUE);
        } else {
          GST_INFO_OBJECT (element, "not flushing bus, auto-flushing disabled");
        }
        gst_object_unref (bus);
      }
      break;
    }
  }
  return result;

  /* ERRORS */
invalid_clock:
  {
    /* we generate this error when the selected clock was not
     * accepted by some element */
    GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
        (_("Selected clock cannot be used in pipeline.")),
        ("Pipeline cannot operate with selected clock"));
    GST_DEBUG_OBJECT (pipeline,
        "Pipeline cannot operate with selected clock %p", clock);
    if (clock)
      gst_object_unref (clock);
    return GST_STATE_CHANGE_FAILURE;
  }
}