diff --git a/libavformat/asfdec.c b/libavformat/asfdec.c
index 3f733f7..a58b8a5 100644
--- a/libavformat/asfdec.c
+++ b/libavformat/asfdec.c
@@ -176,6 +176,8 @@ static void get_tag(AVFormatContext *s, const char *key, int type, int len)
         av_log(s, AV_LOG_DEBUG, "Unsupported value type %d in tag %s.\n", type, key);
         goto finish;
     }
+    if (!memcmp(key, "WM/Track\0", 9))
+        snprintf(value, 2 * len + 1, "%ld", strtol(value, NULL, 10) + 1);
     if (*value)
         av_dict_set(&s->metadata, key, value, 0);
 finish: