diff --git a/libavformat/idcin.c b/libavformat/idcin.c
index 697b97290b999f6350d336e8891a38f2a67c2b93..122fd8ebe4a0023f1579f9c9c635a4dfde37019e 100644
--- a/libavformat/idcin.c
+++ b/libavformat/idcin.c
@@ -290,6 +290,7 @@ static int idcin_read_packet(AVFormatContext *s,
             if (ret < 0)
                 return ret;
             memcpy(pal, palette, AVPALETTE_SIZE);
+            pkt->flags |= AV_PKT_FLAG_KEY;
         }
         pkt->stream_index = idcin->video_stream_index;
         pkt->duration     = 1;