diff --git a/libavcodec/g723_1.c b/libavcodec/g723_1.c
index 11e90e8123..91f1b86170 100644
--- a/libavcodec/g723_1.c
+++ b/libavcodec/g723_1.c
@@ -274,7 +274,7 @@ static int normalize_bits(int num, int width)
     if (num < 0)
         num = ~num;
 
-    return width - av_log2(num);
+    return width - av_log2(num) - 1;
 }
 
 /**