playbin2: add av-offset property

Add av-offset property to control the audio and video sync offset. This can be
used to to manually correct badly synced streams.

See #620529

gst/playback/gstplaybin2.c

@@ -492,6 +492,7 @@ enum
   PROP_CONNECTION_SPEED,
   PROP_BUFFER_SIZE,
   PROP_BUFFER_DURATION,
+  PROP_AV_OFFSET,
   PROP_LAST
 };
 
@@ -786,6 +787,20 @@ gst_play_bin_class_init (GstPlayBinClass * klass)
           "Buffer duration when buffering network streams",
           -1, G_MAXINT64, DEFAULT_BUFFER_DURATION,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+  /**
+   * GstPlayBin2:av-offset:
+   *
+   * Control the synchronisation offset between the audio and video streams.
+   * Positive values make the audio ahead of the video and negative values make
+   * the audio go behind the video.
+   *
+   * Since: 0.10.30
+   */
+  g_object_class_install_property (gobject_klass, PROP_AV_OFFSET,
+      g_param_spec_int64 ("av-offset", "AV Offset",
+          "The synchronisation offset between audio and video in nanoseconds",
+          G_MININT64, G_MAXINT64, 0,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 
   /**
    * GstPlayBin2::about-to-finish
@@ -1777,6 +1792,10 @@ gst_play_bin_set_property (GObject * object, guint prop_id,
     case PROP_BUFFER_DURATION:
       playbin->buffer_duration = g_value_get_int64 (value);
       break;
+    case PROP_AV_OFFSET:
+      gst_play_sink_set_av_offset (playbin->playsink,
+          g_value_get_int64 (value));
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -1945,6 +1964,10 @@ gst_play_bin_get_property (GObject * object, guint prop_id, GValue * value,
       g_value_set_int64 (value, playbin->buffer_duration);
       GST_OBJECT_UNLOCK (playbin);
       break;
+    case PROP_AV_OFFSET:
+      g_value_set_int64 (value,
+          gst_play_sink_get_av_offset (playbin->playsink));
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -2410,8 +2433,8 @@ _playsink_sink_event_probe_cb (GstPad * pad, GstEvent * event,
 
     if (format != GST_FORMAT_TIME)
       data->group->selector[data->type].group_start_accum = GST_CLOCK_TIME_NONE;
-    else if (!GST_CLOCK_TIME_IS_VALID (data->group->selector[data->
+    else if (!GST_CLOCK_TIME_IS_VALID (data->group->selector[data->type].
-                type].group_start_accum))
+            group_start_accum))
       data->group->selector[data->type].group_start_accum = segment->accum;
   } else if (GST_EVENT_TYPE (event) == GST_EVENT_FLUSH_STOP) {
     gst_segment_init (&data->playbin->segments[index], GST_FORMAT_UNDEFINED);
@@ -2943,8 +2966,8 @@ autoplug_continue_cb (GstElement * element, GstPad * pad, GstCaps * caps,
   GstPad *text_sinkpad = NULL;
 
   text_sink =
-      (group->playbin->text_sink) ? gst_object_ref (group->
+      (group->playbin->text_sink) ? gst_object_ref (group->playbin->
-      playbin->text_sink) : NULL;
+      text_sink) : NULL;
   if (text_sink)
     text_sinkpad = gst_element_get_static_pad (text_sink, "sink");
 

gst/playback/gstplaysink.c

@@ -62,6 +62,7 @@ typedef struct
   gboolean sink_volume;         /* if the volume was provided by the sink */
   GstElement *mute;             /* element with the mute property */
   GstElement *sink;
+  GstElement *ts_offset;
 } GstPlayAudioChain;
 
 typedef struct
@@ -81,6 +82,7 @@ typedef struct
   GstElement *scale;
   GstElement *sink;
   gboolean async;
+  GstElement *ts_offset;
 } GstPlayVideoChain;
 
 typedef struct
@@ -168,6 +170,7 @@ struct _GstPlaySink
   gint count;
   gboolean volume_changed;      /* volume/mute changed while no audiochain */
   gboolean mute_changed;        /* ... has been created yet */
+  gint64 av_offset;
 };
 
 struct _GstPlaySinkClass
@@ -215,6 +218,7 @@ enum
   PROP_SUBTITLE_ENCODING,
   PROP_VIS_PLUGIN,
   PROP_FRAME,
+  PROP_AV_OFFSET,
   PROP_LAST
 };
 
@@ -247,6 +251,8 @@ static void notify_volume_cb (GObject * object, GParamSpec * pspec,
 static void notify_mute_cb (GObject * object, GParamSpec * pspec,
     GstPlaySink * playsink);
 
+static void update_av_offset (GstPlaySink * playsink);
+
 /* static guint gst_play_sink_signals[LAST_SIGNAL] = { 0 }; */
 
 G_DEFINE_TYPE (GstPlaySink, gst_play_sink, GST_TYPE_BIN);
@@ -312,7 +318,6 @@ gst_play_sink_class_init (GstPlaySinkClass * klass)
           GST_TYPE_ELEMENT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
   /**
    * GstPlaySink:frame:
-   * @playsink: a #GstPlaySink
    *
    * Get the currently rendered or prerolled frame in the video sink.
    * The #GstCaps on the buffer will describe the format of the buffer.
@@ -323,6 +328,20 @@ gst_play_sink_class_init (GstPlaySinkClass * klass)
       gst_param_spec_mini_object ("frame", "Frame",
           "The last frame (NULL = no video available)",
           GST_TYPE_BUFFER, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
+  /**
+   * GstPlaySink:av-offset:
+   *
+   * Control the synchronisation offset between the audio and video streams.
+   * Positive values make the audio ahead of the video and negative values make
+   * the audio go behind the video.
+   *
+   * Since: 0.10.30
+   */
+  g_object_class_install_property (gobject_klass, PROP_AV_OFFSET,
+      g_param_spec_int64 ("av-offset", "AV Offset",
+          "The synchronisation offset between audio and video in nanoseconds",
+          G_MININT64, G_MAXINT64, 0,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 
   g_signal_new ("reconfigure", G_TYPE_FROM_CLASS (klass),
       G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION, G_STRUCT_OFFSET (GstPlaySinkClass,
@@ -1168,6 +1187,11 @@ gen_video_chain (GstPlaySink * playsink, gboolean raw, gboolean async,
     chain->async = TRUE;
   }
 
+  /* find ts-offset element */
+  chain->ts_offset =
+      gst_play_sink_find_property_sinks (playsink, chain->sink, "ts-offset",
+      G_TYPE_INT64);
+
   /* create a bin to hold objects, as we create them we add them to this bin so
    * that when something goes wrong we only need to unref the bin */
   chain->chain.bin = gst_bin_new ("vbin");
@@ -1313,6 +1337,11 @@ setup_video_chain (GstPlaySink * playsink, gboolean raw, gboolean async,
   if (ret == GST_STATE_CHANGE_FAILURE)
     return FALSE;
 
+  /* find ts-offset element */
+  chain->ts_offset =
+      gst_play_sink_find_property_sinks (playsink, chain->sink, "ts-offset",
+      G_TYPE_INT64);
+
   /* if we can disable async behaviour of the sink, we can avoid adding a
    * queue for the audio chain. */
   elem =
@@ -1588,6 +1617,11 @@ gen_audio_chain (GstPlaySink * playsink, gboolean raw, gboolean queue)
     prev = NULL;
   }
 
+  /* find ts-offset element */
+  chain->ts_offset =
+      gst_play_sink_find_property_sinks (playsink, chain->sink, "ts-offset",
+      G_TYPE_INT64);
+
   /* check if the sink, or something within the sink, has the volume property.
    * If it does we don't need to add a volume element.  */
   elem =
@@ -1791,6 +1825,11 @@ setup_audio_chain (GstPlaySink * playsink, gboolean raw, gboolean queue)
   if (ret == GST_STATE_CHANGE_FAILURE)
     return FALSE;
 
+  /* find ts-offset element */
+  chain->ts_offset =
+      gst_play_sink_find_property_sinks (playsink, chain->sink, "ts-offset",
+      G_TYPE_INT64);
+
   /* check if the sink, or something within the sink, has the volume property.
    * If it does we don't need to add a volume element.  */
   elem =
@@ -2318,7 +2357,7 @@ gst_play_sink_reconfigure (GstPlaySink * playsink)
     if (playsink->text_pad && !playsink->textchain)
       gst_ghost_pad_set_target (GST_GHOST_PAD_CAST (playsink->text_pad), NULL);
   }
-
+  update_av_offset (playsink);
   do_async_done (playsink);
   GST_PLAY_SINK_UNLOCK (playsink);
 
@@ -2439,6 +2478,46 @@ gst_play_sink_get_subtitle_encoding (GstPlaySink * playsink)
   return result;
 }
 
+static void
+update_av_offset (GstPlaySink * playsink)
+{
+  gint64 av_offset;
+  GstPlayAudioChain *achain;
+  GstPlayVideoChain *vchain;
+
+  av_offset = playsink->av_offset;
+  achain = (GstPlayAudioChain *) playsink->audiochain;
+  vchain = (GstPlayVideoChain *) playsink->videochain;
+
+  if (achain && vchain && achain->ts_offset && vchain->ts_offset) {
+    g_object_set (achain->ts_offset, "ts-offset", MAX (0, -av_offset), NULL);
+    g_object_set (vchain->ts_offset, "ts-offset", MAX (0, av_offset), NULL);
+  } else {
+    GST_LOG_OBJECT (playsink, "no ts_offset elements");
+  }
+}
+
+void
+gst_play_sink_set_av_offset (GstPlaySink * playsink, gint64 av_offset)
+{
+  GST_PLAY_SINK_LOCK (playsink);
+  playsink->av_offset = av_offset;
+  update_av_offset (playsink);
+  GST_PLAY_SINK_UNLOCK (playsink);
+}
+
+gint64
+gst_play_sink_get_av_offset (GstPlaySink * playsink)
+{
+  gint64 result;
+
+  GST_PLAY_SINK_LOCK (playsink);
+  result = playsink->av_offset;
+  GST_PLAY_SINK_UNLOCK (playsink);
+
+  return result;
+}
+
 /**
  * gst_play_sink_get_last_frame:
  * @playsink: a #GstPlaySink
@@ -2969,6 +3048,9 @@ gst_play_sink_set_property (GObject * object, guint prop_id,
     case PROP_VIS_PLUGIN:
       gst_play_sink_set_vis_plugin (playsink, g_value_get_object (value));
       break;
+    case PROP_AV_OFFSET:
+      gst_play_sink_set_av_offset (playsink, g_value_get_int64 (value));
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, spec);
       break;
@@ -3004,6 +3086,9 @@ gst_play_sink_get_property (GObject * object, guint prop_id,
     case PROP_FRAME:
       gst_value_take_buffer (value, gst_play_sink_get_last_frame (playsink));
       break;
+    case PROP_AV_OFFSET:
+      g_value_set_int64 (value, gst_play_sink_get_av_offset (playsink));
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, spec);
       break;

gst/playback/gstplaysink.h

@@ -91,6 +91,9 @@ gchar *          gst_play_sink_get_font_desc  (GstPlaySink *playsink);
 void             gst_play_sink_set_subtitle_encoding  (GstPlaySink *playsink, const gchar * encoding);
 gchar *          gst_play_sink_get_subtitle_encoding  (GstPlaySink *playsink);
 
+void             gst_play_sink_set_av_offset  (GstPlaySink *playsink, gint64 av_offset);
+gint64           gst_play_sink_get_av_offset  (GstPlaySink *playsink);
+
 GstBuffer *      gst_play_sink_get_last_frame (GstPlaySink * playsink);
 GstBuffer *      gst_play_sink_convert_frame  (GstPlaySink * playsink, GstCaps * caps);