decklink{audio,video}src: Only start the streams once both sources are ready and we are in PLAYING

Otherwise we might start the streams before the audio or video streams are
actually enabled, and then error out later because they are enabled to late.

We enable the streams when getting the caps, which might be *after* we were
set to PLAYING state.

3 files changed, 38 insertions, 14 deletions

diff --git a/sys/decklink/gstdecklink.h b/sys/decklink/gstdecklink.h
index c85f8b24e..e58987e4b 100644
--- a/sys/decklink/gstdecklink.h
+++ b/sys/decklink/gstdecklink.h
@@ -148,7 +148,6 @@ struct _GstDecklinkOutput {
   /* Set by the audio sink */
   GstClock *audio_clock;
 
-  /* <private> */
   GstElement *audiosink;
   gboolean audio_enabled;
   GstElement *videosink;
@@ -176,11 +175,11 @@ struct _GstDecklinkInput {
   /* Set by the audio source */
   void (*got_audio_packet) (GstElement *videosrc, IDeckLinkAudioInputPacket * packet, GstClockTime capture_time);
 
-  /* <private> */
   GstElement *audiosrc;
   gboolean audio_enabled;
   GstElement *videosrc;
   gboolean video_enabled;
+  void (*start_streams) (GstElement *videosrc);
 };
 
 GstDecklinkOutput * gst_decklink_acquire_nth_output (gint n, GstElement * sink, gboolean is_audio);
diff --git a/sys/decklink/gstdecklinkaudiosrc.cpp b/sys/decklink/gstdecklinkaudiosrc.cpp
index 99b8a0fc3..1a63f379b 100644
--- a/sys/decklink/gstdecklinkaudiosrc.cpp
+++ b/sys/decklink/gstdecklinkaudiosrc.cpp
@@ -381,6 +381,8 @@ gst_decklink_audio_src_set_caps (GstBaseSrc * bsrc, GstCaps * caps)
 
   g_mutex_lock (&self->input->lock);
   self->input->audio_enabled = TRUE;
+  if (self->input->start_streams)
+    self->input->start_streams (self->input->videosrc);
   g_mutex_unlock (&self->input->lock);
 
   return TRUE;
@@ -657,6 +659,8 @@ gst_decklink_audio_src_close (GstDecklinkAudioSrc * self)
     g_mutex_lock (&self->input->lock);
     self->input->got_audio_packet = NULL;
     self->input->audio_enabled = FALSE;
+    if (self->input->start_streams)
+      self->input->start_streams (self->input->videosrc);
     g_mutex_unlock (&self->input->lock);
 
     self->input->input->DisableAudioInput ();
diff --git a/sys/decklink/gstdecklinkvideosrc.cpp b/sys/decklink/gstdecklinkvideosrc.cpp
index 095a7c65f..e015c5d32 100644
--- a/sys/decklink/gstdecklinkvideosrc.cpp
+++ b/sys/decklink/gstdecklinkvideosrc.cpp
@@ -100,6 +100,8 @@ static GstFlowReturn gst_decklink_video_src_create (GstPushSrc * psrc,
 static gboolean gst_decklink_video_src_open (GstDecklinkVideoSrc * self);
 static gboolean gst_decklink_video_src_close (GstDecklinkVideoSrc * self);
 
+static void gst_decklink_video_src_start_streams (GstElement * element);
+
 #define parent_class gst_decklink_video_src_parent_class
 G_DEFINE_TYPE (GstDecklinkVideoSrc, gst_decklink_video_src, GST_TYPE_PUSH_SRC);
 
@@ -329,6 +331,8 @@ gst_decklink_video_src_set_caps (GstBaseSrc * bsrc, GstCaps * caps)
   g_mutex_lock (&self->input->lock);
   self->input->mode = mode;
   self->input->video_enabled = TRUE;
+  if (self->input->start_streams)
+    self->input->start_streams (self->input->videosrc);
   g_mutex_unlock (&self->input->lock);
 
   return TRUE;
@@ -551,6 +555,7 @@ gst_decklink_video_src_open (GstDecklinkVideoSrc * self)
   g_mutex_lock (&self->input->lock);
   self->input->mode = mode;
   self->input->got_video_frame = gst_decklink_video_src_got_frame;
+  self->input->start_streams = gst_decklink_video_src_start_streams;
   self->input->clock_start_time = GST_CLOCK_TIME_NONE;
   self->input->clock_last_time = 0;
   self->input->clock_offset = 0;
@@ -570,6 +575,8 @@ gst_decklink_video_src_close (GstDecklinkVideoSrc * self)
     self->input->got_video_frame = NULL;
     self->input->mode = NULL;
     self->input->video_enabled = FALSE;
+    if (self->input->start_streams)
+      self->input->start_streams (self->input->videosrc);
     g_mutex_unlock (&self->input->lock);
 
     self->input->input->DisableVideoInput ();
@@ -581,6 +588,29 @@ gst_decklink_video_src_close (GstDecklinkVideoSrc * self)
   return TRUE;
 }
 
+static void
+gst_decklink_video_src_start_streams (GstElement * element)
+{
+  GstDecklinkVideoSrc *self = GST_DECKLINK_VIDEO_SRC_CAST (element);
+  HRESULT res;
+
+  if (self->input->video_enabled && (!self->input->audiosrc
+          || self->input->audio_enabled)
+      && GST_STATE (self) == GST_STATE_PLAYING) {
+    GST_DEBUG_OBJECT (self, "Starting streams");
+    res = self->input->input->StartStreams ();
+    if (res != S_OK) {
+      GST_ELEMENT_ERROR (self, STREAM, FAILED,
+          (NULL), ("Failed to start streams: 0x%08x", res));
+      return;
+    }
+    self->input->started = TRUE;
+    self->input->clock_restart = TRUE;
+  } else {
+    GST_DEBUG_OBJECT (self, "Not starting streams yet");
+  }
+}
+
 static GstStateChangeReturn
 gst_decklink_video_src_change_state (GstElement * element,
     GstStateChange transition)
@@ -588,7 +618,6 @@ gst_decklink_video_src_change_state (GstElement * element,
   GstDecklinkVideoSrc *self = GST_DECKLINK_VIDEO_SRC_CAST (element);
   GstStateChangeReturn ret;
 
-
   switch (transition) {
     case GST_STATE_CHANGE_NULL_TO_READY:
       if (!gst_decklink_video_src_open (self)) {
@@ -660,19 +689,11 @@ gst_decklink_video_src_change_state (GstElement * element,
       break;
     }
     case GST_STATE_CHANGE_PAUSED_TO_PLAYING:{
-      HRESULT res;
-
-      GST_DEBUG_OBJECT (self, "Starting streams");
-      res = self->input->input->StartStreams ();
-      if (res != S_OK) {
-        GST_ELEMENT_ERROR (self, STREAM, FAILED,
-            (NULL), ("Failed to start streams: 0x%08x", res));
-        ret = GST_STATE_CHANGE_FAILURE;
-      }
       g_mutex_lock (&self->input->lock);
-      self->input->started = TRUE;
-      self->input->clock_restart = TRUE;
+      if (self->input->start_streams)
+        self->input->start_streams (self->input->videosrc);
       g_mutex_unlock (&self->input->lock);
+
       break;
     }
     case GST_STATE_CHANGE_READY_TO_NULL: