diff --git a/docs/plugins/gst_plugins_cache.json b/docs/plugins/gst_plugins_cache.json
index 02da7405d4..9a484b301b 100644
--- a/docs/plugins/gst_plugins_cache.json
+++ b/docs/plugins/gst_plugins_cache.json
@@ -3451,17 +3451,42 @@
                 "long-name": "Line 21 CC Decoder",
                 "pad-templates": {
                     "sink": {
-                        "caps": "video/x-raw:\n         format: { I420, YUY2, YVYU, UYVY, VYUY, v210 }\n interlace-mode: interleaved\n",
+                        "caps": "video/x-raw:\n         format: { I420, YUY2, YVYU, UYVY, VYUY, v210 }\n",
                         "direction": "sink",
                         "presence": "always"
                     },
                     "src": {
-                        "caps": "video/x-raw:\n         format: { I420, YUY2, YVYU, UYVY, VYUY, v210 }\n interlace-mode: interleaved\n",
+                        "caps": "video/x-raw:\n         format: { I420, YUY2, YVYU, UYVY, VYUY, v210 }\n",
                         "direction": "src",
                         "presence": "always"
                     }
                 },
-                "properties": {},
+                "properties": {
+                    "mode": {
+                        "blurb": "Control whether and how detected CC meta should be inserted in the list of existing CC meta on a frame (if any).",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "add (0)",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "GstLine21DecoderMode",
+                        "writable": true
+                    },
+                    "ntsc-only": {
+                        "blurb": "Whether line 21 decoding should only be attempted when the input resolution matches NTSC",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "false",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    }
+                },
                 "rank": "none"
             },
             "line21encoder": {
@@ -3554,6 +3579,26 @@
                         "value": "3"
                     }
                 ]
+            },
+            "GstLine21DecoderMode": {
+                "kind": "enum",
+                "values": [
+                    {
+                        "desc": "add new CC meta on top of other CC meta, if any",
+                        "name": "add",
+                        "value": "0"
+                    },
+                    {
+                        "desc": "ignore CC if a CC meta was already present",
+                        "name": "drop",
+                        "value": "1"
+                    },
+                    {
+                        "desc": "replace existing CC meta",
+                        "name": "replace",
+                        "value": "2"
+                    }
+                ]
             }
         },
         "package": "GStreamer Bad Plug-ins",
diff --git a/ext/closedcaption/gstline21dec.c b/ext/closedcaption/gstline21dec.c
index 489bd00982..4e5b7702c6 100644
--- a/ext/closedcaption/gstline21dec.c
+++ b/ext/closedcaption/gstline21dec.c
@@ -56,7 +56,7 @@ enum
 #define DEFAULT_NTSC_ONLY FALSE
 #define DEFAULT_MODE GST_LINE_21_DECODER_MODE_ADD
 
-#define CAPS "video/x-raw, format={ I420, YUY2, YVYU, UYVY, VYUY, v210 }, interlace-mode=interleaved"
+#define CAPS "video/x-raw, format={ I420, YUY2, YVYU, UYVY, VYUY, v210 }"
 
 static GstStaticPadTemplate sinktemplate = GST_STATIC_PAD_TEMPLATE ("sink",
     GST_PAD_SINK,
@@ -216,6 +216,8 @@ gst_line_21_decoder_class_init (GstLine21DecoderClass * klass)
   GST_DEBUG_CATEGORY_INIT (gst_line_21_decoder_debug, "line21decoder",
       0, "Line 21 CC Decoder");
   vbi_initialize_gst_debug ();
+
+  gst_type_mark_as_plugin_api (GST_TYPE_LINE_21_DECODER_MODE, 0);
 }
 
 static void
@@ -288,6 +290,12 @@ gst_line_21_decoder_set_info (GstVideoFilter * filter,
   /* Scan the next frame from the first line */
   self->line21_offset = -1;
 
+  if (!GST_VIDEO_INFO_IS_INTERLACED (in_info)) {
+    GST_DEBUG_OBJECT (filter, "Only interlaced formats are supported");
+    self->compatible_format = FALSE;
+    return TRUE;
+  }
+
   if (GST_VIDEO_INFO_WIDTH (in_info) != 720) {
     GST_DEBUG_OBJECT (filter, "Only 720 pixel wide formats are supported");
     self->compatible_format = FALSE;