diff --git a/subprojects/gst-libav/docs/gst_plugins_cache.json b/subprojects/gst-libav/docs/gst_plugins_cache.json
index bb075d1a04..61356ffd40 100644
--- a/subprojects/gst-libav/docs/gst_plugins_cache.json
+++ b/subprojects/gst-libav/docs/gst_plugins_cache.json
@@ -137857,7 +137857,7 @@
                         "presence": "always"
                     },
                     "video_%%u": {
-                        "caps": "video/x-vp8:\nvideo/x-vp9:\nvideo/x-av1:\n",
+                        "caps": "video/x-vp8:\nvideo/x-vp9:\nvideo/x-av1:\n  stream-format: obu-stream\n      alignment: { (string)tu, (string)frame }\n",
                         "direction": "sink",
                         "presence": "request"
                     }
diff --git a/subprojects/gst-libav/ext/libav/gstavcodecmap.c b/subprojects/gst-libav/ext/libav/gstavcodecmap.c
index a27bea1375..716df19f26 100644
--- a/subprojects/gst-libav/ext/libav/gstavcodecmap.c
+++ b/subprojects/gst-libav/ext/libav/gstavcodecmap.c
@@ -2358,7 +2358,21 @@ gst_ffmpeg_codecid_to_caps (enum AVCodecID codec_id,
     case AV_CODEC_ID_AV1:
       caps =
           gst_ff_vid_caps_new (context, NULL, codec_id, encode, "video/x-av1",
-          NULL);
+          "stream-format", G_TYPE_STRING, "obu-stream", NULL);
+      if (encode) {
+        GValue arr = { 0, };
+        GValue item = { 0, };
+        g_value_init (&arr, GST_TYPE_LIST);
+        g_value_init (&item, G_TYPE_STRING);
+        g_value_set_string (&item, "tu");
+        gst_value_list_append_value (&arr, &item);
+        g_value_set_string (&item, "frame");
+        gst_value_list_append_value (&arr, &item);
+        g_value_unset (&item);
+
+        gst_caps_set_value (caps, "alignment", &arr);
+        g_value_unset (&arr);
+      }
       break;
     default:
       GST_DEBUG ("Unknown codec ID %d, please add mapping here", codec_id);
@@ -4153,6 +4167,9 @@ gst_ffmpeg_caps_to_codecid (const GstCaps * caps, AVCodecContext * context)
   } else if (!strcmp (mimetype, "video/x-vp9")) {
     id = AV_CODEC_ID_VP9;
     video = TRUE;
+  } else if (!strcmp (mimetype, "video/x-av1")) {
+    id = AV_CODEC_ID_AV1;
+    video = TRUE;
   } else if (!strcmp (mimetype, "video/x-flash-screen")) {
     id = AV_CODEC_ID_FLASHSV;
     video = TRUE;