flvmux: Add encoder metadata to the header

And also add a property for setting this. By default it has the same
value as the metadatacreator metadata.

Various software is using encoder instead of metadatacreator, others are
using them both for different purposes. As such it's useful to have
support for setting both here.

gst/flv/gstflvmux.c

@@ -53,7 +53,8 @@ enum
 {
   PROP_0,
   PROP_STREAMABLE,
-  PROP_METADATACREATOR
+  PROP_METADATACREATOR,
+  PROP_ENCODER
 };
 
 #define DEFAULT_STREAMABLE FALSE
@@ -230,6 +231,11 @@ gst_flv_mux_class_init (GstFlvMuxClass * klass)
           "The value of metadatacreator in the meta packet.",
           NULL, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 
+  g_object_class_install_property (gobject_class, PROP_ENCODER,
+      g_param_spec_string ("encoder", "encoder",
+          "The value of encoder in the meta packet.",
+          NULL, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
   gstaggregator_class->create_new_pad =
       GST_DEBUG_FUNCPTR (gst_flv_mux_create_new_pad);
   gstelement_class->release_pad = GST_DEBUG_FUNCPTR (gst_flv_mux_release_pad);
@@ -265,6 +271,7 @@ gst_flv_mux_init (GstFlvMux * mux)
   /* property */
   mux->streamable = DEFAULT_STREAMABLE;
   mux->metadatacreator = g_strdup (DEFAULT_METADATACREATOR);
+  mux->encoder = g_strdup (DEFAULT_METADATACREATOR);
 
   mux->new_tags = FALSE;
 
@@ -278,6 +285,7 @@ gst_flv_mux_finalize (GObject * object)
 
   gst_flv_mux_reset (GST_ELEMENT (object));
   g_free (mux->metadatacreator);
+  g_free (mux->encoder);
 
   G_OBJECT_CLASS (gst_flv_mux_parent_class)->finalize (object);
 }
@@ -1059,7 +1067,18 @@ tags:
   data[19] = (strlen (mux->metadatacreator)) & 0xff;
   memcpy (&data[20], mux->metadatacreator, strlen (mux->metadatacreator));
   script_tag = gst_buffer_append (script_tag, tmp);
+  tags_written++;
 
+  _gst_buffer_new_and_alloc (2 + 7 + 1 + 2 + strlen (mux->encoder),
+      &tmp, &data);
+  data[0] = 0;                  /* 7 bytes name */
+  data[1] = 7;
+  memcpy (&data[2], "encoder", 7);
+  data[9] = 2;                  /* string */
+  data[10] = (strlen (mux->encoder) >> 8) & 0xff;
+  data[11] = (strlen (mux->encoder)) & 0xff;
+  memcpy (&data[12], mux->encoder, strlen (mux->encoder));
+  script_tag = gst_buffer_append (script_tag, tmp);
   tags_written++;
 
   {
@@ -1908,6 +1927,9 @@ gst_flv_mux_get_property (GObject * object,
     case PROP_METADATACREATOR:
       g_value_set_string (value, mux->metadatacreator);
       break;
+    case PROP_ENCODER:
+      g_value_set_string (value, mux->encoder);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -1939,6 +1961,15 @@ gst_flv_mux_set_property (GObject * object,
         mux->metadatacreator = g_value_dup_string (value);
       }
       break;
+    case PROP_ENCODER:
+      g_free (mux->encoder);
+      if (!g_value_get_string (value)) {
+        GST_WARNING_OBJECT (mux, "encoder property can not be NULL");
+        mux->encoder = g_strdup (DEFAULT_METADATACREATOR);
+      } else {
+        mux->encoder = g_value_dup_string (value);
+      }
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;

gst/flv/gstflvmux.h

@@ -93,6 +93,7 @@ struct _GstFlvMux {
   GstFlvMuxPad *video_pad;
   gboolean streamable;
   gchar *metadatacreator;
+  gchar *encoder;
 
   GstTagList *tags;
   gboolean new_tags;