gstvideoaggregator: expose max-last-buffer-repeat property on pads

This can be used to have compositor display either the background
or a stream on a lower zorder after a live input stream freezes
for a certain amount of time, for example because of network
issues.
This commit is contained in:
Mathieu Duponchelle 2020-03-27 02:48:39 +01:00
parent caca46e0e6
commit fb1c284026

View file

@ -55,11 +55,13 @@ static void gst_video_aggregator_reset_qos (GstVideoAggregator * vagg);
#define DEFAULT_PAD_ZORDER 0
#define DEFAULT_PAD_REPEAT_AFTER_EOS FALSE
#define DEFAULT_PAD_MAX_LAST_BUFFER_REPEAT GST_CLOCK_TIME_NONE
enum
{
PROP_PAD_0,
PROP_PAD_ZORDER,
PROP_PAD_REPEAT_AFTER_EOS,
PROP_PAD_MAX_LAST_BUFFER_REPEAT,
};
@ -71,6 +73,7 @@ struct _GstVideoAggregatorPadPrivate
/* properties */
guint zorder;
gboolean repeat_after_eos;
GstClockTime max_last_buffer_repeat;
/* Subclasses can force an alpha channel in the (input thus output)
* colorspace format */
@ -99,6 +102,9 @@ gst_video_aggregator_pad_get_property (GObject * object, guint prop_id,
case PROP_PAD_REPEAT_AFTER_EOS:
g_value_set_boolean (value, pad->priv->repeat_after_eos);
break;
case PROP_PAD_MAX_LAST_BUFFER_REPEAT:
g_value_set_uint64 (value, pad->priv->max_last_buffer_repeat);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
@ -131,6 +137,9 @@ gst_video_aggregator_pad_set_property (GObject * object, guint prop_id,
case PROP_PAD_REPEAT_AFTER_EOS:
pad->priv->repeat_after_eos = g_value_get_boolean (value);
break;
case PROP_PAD_MAX_LAST_BUFFER_REPEAT:
pad->priv->max_last_buffer_repeat = g_value_get_uint64 (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
@ -218,6 +227,36 @@ gst_video_aggregator_pad_class_init (GstVideoAggregatorPadClass * klass)
DEFAULT_PAD_REPEAT_AFTER_EOS,
G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
/**
*
* GstVideoAggregator:max-last-buffer-repeat:
*
* Repeat last buffer for time (in ns, -1 = until EOS).
* The default behaviour is for the last buffer received on a pad to be
* aggregated until a new buffer is received.
*
* Setting this property causes the last buffer to be discarded once the
* running time of the output buffer is `max-last-buffer-repeat` nanoseconds
* past its end running time. When the buffer didn't have a duration, the
* comparison is made against its running start time.
*
* This is useful in live scenarios: when a stream encounters a temporary
* networking problem, a #GstVideoAggregator subclass can then fall back to
* displaying a lower z-order stream, or the background.
*
* Setting this property doesn't affect the behaviour on EOS.
*
* Since: 1.18
*/
g_object_class_install_property (gobject_class,
PROP_PAD_MAX_LAST_BUFFER_REPEAT,
g_param_spec_uint64 ("max-last-buffer-repeat", "Max Last Buffer Repeat",
"Repeat last buffer for time (in ns, -1=until EOS), "
"behaviour on EOS is not affected", 0, G_MAXUINT64,
DEFAULT_PAD_MAX_LAST_BUFFER_REPEAT,
G_PARAM_READWRITE | GST_PARAM_MUTABLE_PLAYING |
G_PARAM_STATIC_STRINGS));
aggpadclass->flush = GST_DEBUG_FUNCPTR (_flush_pad);
aggpadclass->skip_buffer =
GST_DEBUG_FUNCPTR (gst_video_aggregator_pad_skip_buffer);
@ -233,6 +272,7 @@ gst_video_aggregator_pad_init (GstVideoAggregatorPad * vaggpad)
vaggpad->priv->zorder = DEFAULT_PAD_ZORDER;
vaggpad->priv->repeat_after_eos = DEFAULT_PAD_REPEAT_AFTER_EOS;
vaggpad->priv->max_last_buffer_repeat = DEFAULT_PAD_MAX_LAST_BUFFER_REPEAT;
memset (&vaggpad->priv->prepared_frame, 0, sizeof (GstVideoFrame));
}
@ -1459,6 +1499,7 @@ gst_video_aggregator_fill_queues (GstVideoAggregator * vagg,
}
gst_buffer_unref (buf);
gst_aggregator_pad_drop_buffer (bpad);
pad->priv->start_time = start_time;
need_more_data = TRUE;
continue;
}
@ -1470,7 +1511,8 @@ gst_video_aggregator_fill_queues (GstVideoAggregator * vagg,
need_reconfigure = TRUE;
pad->priv->pending_vinfo.finfo = NULL;
}
/* FIXME: Set start_time and end_time to something here? */
/* FIXME: Set end_time to something here? */
pad->priv->start_time = start_time;
gst_buffer_unref (buf);
GST_DEBUG_OBJECT (pad, "buffer duration is -1");
continue;
@ -1568,18 +1610,41 @@ gst_video_aggregator_fill_queues (GstVideoAggregator * vagg,
if (pad->priv->end_time != -1) {
if (pad->priv->end_time <= output_start_running_time) {
pad->priv->start_time = pad->priv->end_time = -1;
if (!is_eos) {
GST_DEBUG ("I just need more data");
GST_DEBUG_OBJECT (pad, "I just need more data");
if (GST_CLOCK_TIME_IS_VALID (pad->priv->max_last_buffer_repeat)) {
if (output_start_running_time - pad->priv->end_time >
pad->priv->max_last_buffer_repeat) {
pad->priv->start_time = pad->priv->end_time = -1;
gst_buffer_replace (&pad->priv->buffer, NULL);
}
} else {
pad->priv->start_time = pad->priv->end_time = -1;
}
need_more_data = TRUE;
} else {
gst_buffer_replace (&pad->priv->buffer, NULL);
pad->priv->start_time = pad->priv->end_time = -1;
}
} else if (is_eos) {
eos = FALSE;
}
} else if (is_eos) {
gst_buffer_replace (&pad->priv->buffer, NULL);
} else if (pad->priv->start_time != -1) {
/* When the current buffer didn't have a duration, but
* max-last-buffer-repeat was set, we use start_time as
* the comparison point
*/
if (pad->priv->start_time <= output_start_running_time) {
if (GST_CLOCK_TIME_IS_VALID (pad->priv->max_last_buffer_repeat)) {
if (output_start_running_time - pad->priv->start_time >
pad->priv->max_last_buffer_repeat) {
pad->priv->start_time = pad->priv->end_time = -1;
gst_buffer_replace (&pad->priv->buffer, NULL);
}
}
}
}
}
}