diff --git a/libavformat/isom.c b/libavformat/isom.c
index 92b743ede5..e6cd26369b 100644
--- a/libavformat/isom.c
+++ b/libavformat/isom.c
@@ -166,6 +166,7 @@ const AVCodecTag ff_codec_movvideo_tags[] = {
     { AV_CODEC_ID_H264, MKTAG('a', 'i', '1', '6') }, /* AVC-Intra 100M 1080i60 */
     { AV_CODEC_ID_H264, MKTAG('A', 'V', 'i', 'n') }, /* AVC-Intra with implicit SPS/PPS */
     { AV_CODEC_ID_H264, MKTAG('a', 'i', 'v', 'x') }, /* XAVC 4:2:2 10bit */
+    { AV_CODEC_ID_H264, MKTAG('r', 'v', '6', '4') }, /* X-Com Radvision */
 
     { AV_CODEC_ID_MPEG1VIDEO, MKTAG('m', '1', 'v', ' ') },
     { AV_CODEC_ID_MPEG1VIDEO, MKTAG('m', '1', 'v', '1') }, /* Apple MPEG-1 Camcorder */