diff --git a/libavformat/isom.c b/libavformat/isom.c
index eb06a4392e..1228d56d3a 100644
--- a/libavformat/isom.c
+++ b/libavformat/isom.c
@@ -71,7 +71,7 @@ const AVCodecTag codec_movvideo_tags[] = {
 
     { CODEC_ID_RAWVIDEO, MKTAG('r', 'a', 'w', ' ') }, /* Uncompressed RGB */
     { CODEC_ID_RAWVIDEO, MKTAG('y', 'u', 'v', '2') }, /* Uncompressed YUV422 */
-    { CODEC_ID_RAWVIDEO, MKTAG('A', 'V', 'U', 'I') }, /* YUV with alpha-channel (AVID Uncompressed) */
+    { CODEC_ID_RAWVIDEO, MKTAG('A', 'V', 'U', 'I') }, /* AVID Uncompressed deinterleaved UYVY422 */
     { CODEC_ID_RAWVIDEO, MKTAG('2', 'v', 'u', 'y') }, /* UNCOMPRESSED 8BIT 4:2:2 */
     { CODEC_ID_RAWVIDEO, MKTAG('y', 'u', 'v', 's') }, /* same as 2vuy but byte swapped */