decklinkvideosink: Add support for Decklink hardware keying

Add two properties (keyer-mode and keyer-level) to control the built-in hardware keyer of Decklink cards.

https://bugzilla.gnome.org/show_bug.cgi?id=773660

sys/decklink/gstdecklink.cpp

@@ -168,6 +168,25 @@ gst_decklink_timecode_format_get_type (void)
   return (GType) id;
 }
 
+GType
+gst_decklink_keyer_mode_get_type (void)
+{
+  static gsize id = 0;
+  static const GEnumValue keyermodes[] = {
+    {GST_DECKLINK_KEYER_MODE_OFF, "Off", "off"},
+    {GST_DECKLINK_KEYER_MODE_INTERNAL, "Internal", "internal"},
+    {GST_DECKLINK_KEYER_MODE_EXTERNAL, "External", "external"},
+    {0, NULL, NULL}
+  };
+
+  if (g_once_init_enter (&id)) {
+    GType tmp = g_enum_register_static ("GstDecklinkKeyerMode", keyermodes);
+    g_once_init_leave (&id, tmp);
+  }
+
+  return (GType) id;
+}
+
 GType
 gst_decklink_audio_connection_get_type (void)
 {
@@ -298,6 +317,18 @@ static const struct
   /* *INDENT-ON* */
 };
 
+static const struct
+{
+  BMDKeyerMode keymode;
+  GstDecklinkKeyerMode gstkeymode;
+} kmodes[] = {
+  /* *INDENT-OFF* */
+  {bmdKeyerModeOff, GST_DECKLINK_KEYER_MODE_OFF},
+  {bmdKeyerModeInternal, GST_DECKLINK_KEYER_MODE_INTERNAL},
+  {bmdKeyerModeExternal, GST_DECKLINK_KEYER_MODE_EXTERNAL}
+  /* *INDENT-ON* */
+};
+
 const GstDecklinkMode *
 gst_decklink_get_mode (GstDecklinkModeEnum e)
 {
@@ -452,6 +483,25 @@ gst_decklink_timecode_format_to_enum (BMDTimecodeFormat f)
   return GST_DECKLINK_TIMECODE_FORMAT_RP188ANY;
 }
 
+const BMDKeyerMode
+gst_decklink_keyer_mode_from_enum (GstDecklinkKeyerMode m)
+{
+  return kmodes[m].keymode;
+}
+
+const GstDecklinkKeyerMode
+gst_decklink_keyer_mode_to_enum (BMDKeyerMode m)
+{
+  guint i;
+
+  for (i = 0; i < G_N_ELEMENTS (kmodes); i++) {
+    if (kmodes[i].keymode == m)
+      return (GstDecklinkKeyerMode) i;
+  }
+  g_assert_not_reached ();
+  return GST_DECKLINK_KEYER_MODE_OFF;
+}
+
 static const BMDVideoConnection connections[] = {
   (BMDVideoConnection) 0,       /* auto */
   bmdVideoConnectionSDI,
@@ -1177,6 +1227,13 @@ init_devices (gpointer data)
           "0x%08lx", (unsigned long) ret);
     }
 
+    ret = decklink->QueryInterface (IID_IDeckLinkKeyer,
+        (void **) &devices[i].output.keyer);
+
+    /* We only warn of failure to obtain the keyer interface if the keyer
+     * is enabled by keyer_mode
+     */
+
     ret = iterator->Next (&decklink);
     i++;
 

sys/decklink/gstdecklink.h

@@ -156,11 +156,32 @@ typedef enum {
 #define GST_TYPE_DECKLINK_TIMECODE_FORMAT (gst_decklink_timecode_format_get_type ())
 GType gst_decklink_timecode_format_get_type (void);
 
+typedef enum
+{
+  GST_DECKLINK_KEYER_MODE_OFF,
+  GST_DECKLINK_KEYER_MODE_INTERNAL,
+  GST_DECKLINK_KEYER_MODE_EXTERNAL
+} GstDecklinkKeyerMode;
+#define GST_TYPE_DECKLINK_KEYER_MODE (gst_decklink_keyer_mode_get_type ())
+GType gst_decklink_keyer_mode_get_type (void);
+
+/* Enum BMDKeyerMode options of off, internal and external @@@ DJ @@@ */
+
+typedef uint32_t BMDKeyerMode;
+enum _BMDKeyerMode
+{
+  bmdKeyerModeOff = /* 'off' */ 0,
+  bmdKeyerModeInternal = /* 'int' */ 1,
+  bmdKeyerModeExternal = /* 'ext' */ 2
+};
+
 const BMDPixelFormat gst_decklink_pixel_format_from_type (GstDecklinkVideoFormat t);
 const gint gst_decklink_bpp_from_type (GstDecklinkVideoFormat t);
 const GstDecklinkVideoFormat gst_decklink_type_from_video_format (GstVideoFormat f);
 const BMDTimecodeFormat gst_decklink_timecode_format_from_enum (GstDecklinkTimecodeFormat f);
 const GstDecklinkTimecodeFormat gst_decklink_timecode_format_to_enum (BMDTimecodeFormat f);
+const BMDKeyerMode gst_decklink_keyer_mode_from_enum (GstDecklinkKeyerMode m);
+const GstDecklinkKeyerMode gst_decklink_keyer_mode_to_enum (BMDKeyerMode m);
 
 typedef struct _GstDecklinkMode GstDecklinkMode;
 struct _GstDecklinkMode {
@@ -187,6 +208,7 @@ struct _GstDecklinkOutput {
   IDeckLink *device;
   IDeckLinkOutput *output;
   IDeckLinkAttributes *attributes;
+  IDeckLinkKeyer *keyer;
   GstClock *clock;
   GstClockTime clock_start_time, clock_last_time, clock_epoch;
   GstClockTimeDiff clock_offset;

sys/decklink/gstdecklinkvideosink.cpp

@@ -120,7 +120,9 @@ enum
   PROP_MODE,
   PROP_DEVICE_NUMBER,
   PROP_VIDEO_FORMAT,
-  PROP_TIMECODE_FORMAT
+  PROP_TIMECODE_FORMAT,
+  PROP_KEYER_MODE,
+  PROP_KEYER_LEVEL
 };
 
 static void gst_decklink_video_sink_set_property (GObject * object,
@@ -227,6 +229,20 @@ gst_decklink_video_sink_class_init (GstDecklinkVideoSinkClass * klass)
           (GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
               G_PARAM_CONSTRUCT)));
 
+  g_object_class_install_property (gobject_class, PROP_KEYER_MODE,
+      g_param_spec_enum ("keyer-mode", "Keyer mode",
+          "Keyer mode to be enabled",
+          GST_TYPE_DECKLINK_KEYER_MODE,
+          GST_DECKLINK_KEYER_MODE_OFF,
+          (GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
+              G_PARAM_CONSTRUCT)));
+
+  g_object_class_install_property (gobject_class, PROP_KEYER_LEVEL,
+      g_param_spec_int ("keyer-level", "Keyer level",
+          "Keyer level", 0, 255, 255,
+          (GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
+              G_PARAM_CONSTRUCT)));
+
   templ_caps = gst_decklink_mode_get_template_caps (FALSE);
   templ_caps = gst_caps_make_writable (templ_caps);
   /* For output we support any framerate and only really care about timestamps */
@@ -289,6 +305,14 @@ gst_decklink_video_sink_set_property (GObject * object, guint property_id,
           gst_decklink_timecode_format_from_enum ((GstDecklinkTimecodeFormat)
           g_value_get_enum (value));
       break;
+    case PROP_KEYER_MODE:
+      self->keyer_mode =
+          gst_decklink_keyer_mode_from_enum ((GstDecklinkKeyerMode)
+          g_value_get_enum (value));
+      break;
+    case PROP_KEYER_LEVEL:
+      self->keyer_level = g_value_get_int (value);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
       break;
@@ -315,6 +339,13 @@ gst_decklink_video_sink_get_property (GObject * object, guint property_id,
       g_value_set_enum (value,
           gst_decklink_timecode_format_to_enum (self->timecode_format));
       break;
+    case PROP_KEYER_MODE:
+      g_value_set_enum (value,
+          gst_decklink_keyer_mode_to_enum (self->keyer_mode));
+      break;
+    case PROP_KEYER_LEVEL:
+      g_value_set_int (value, self->keyer_level);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
       break;
@@ -387,6 +418,24 @@ gst_decklink_video_sink_set_caps (GstBaseSink * bsink, GstCaps * caps)
     g_assert (mode != NULL);
   };
 
+  /* enable or disable keyer */
+  if (self->output->keyer != NULL) {
+    if (self->keyer_mode == bmdKeyerModeOff) {
+      self->output->keyer->Disable ();
+    } else if (self->keyer_mode == bmdKeyerModeInternal) {
+      self->output->keyer->Enable (false);
+      self->output->keyer->SetLevel (self->keyer_level);
+    } else if (self->keyer_mode == bmdKeyerModeExternal) {
+      self->output->keyer->Enable (true);
+      self->output->keyer->SetLevel (self->keyer_level);
+    } else {
+      g_assert_not_reached ();
+    }
+  } else if (self->keyer_mode != bmdKeyerModeOff) {
+    GST_WARNING_OBJECT (self, "Failed to set keyer to mode %d",
+        self->keyer_mode);
+  }
+
   /* The timecode_format itself is used when we embed the actual timecode data
    * into the frame. Now we only need to know which of the two standards the
    * timecode format will adhere to: VITC or RP188, and send the appropriate

sys/decklink/gstdecklinkvideosink.h

@@ -53,6 +53,8 @@ struct _GstDecklinkVideoSink
   gint device_number;
   GstDecklinkVideoFormat video_format;
   BMDTimecodeFormat timecode_format;
+  BMDKeyerMode keyer_mode;
+  gint keyer_level;
 
   GstVideoInfo info;