From 2f329db90e5d72ad383a0ba05fde3641a34ef73b Mon Sep 17 00:00:00 2001
From: Mans Rullgard <mans@mansr.com>
Date: Sat, 8 Oct 2011 12:56:54 +0100
Subject: [PATCH] mpeg12enc: use sign_extend() function

Signed-off-by: Mans Rullgard <mans@mansr.com>
---
 libavcodec/mpeg12enc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/mpeg12enc.c b/libavcodec/mpeg12enc.c
index 79c46beef9..f4455be925 100644
--- a/libavcodec/mpeg12enc.c
+++ b/libavcodec/mpeg12enc.c
@@ -27,6 +27,7 @@
 
 #include "avcodec.h"
 #include "dsputil.h"
+#include "mathops.h"
 #include "mpegvideo.h"
 
 #include "mpeg12.h"
@@ -690,8 +691,7 @@ static void mpeg1_encode_motion(MpegEncContext *s, int val, int f_or_b_code)
         int bit_size = f_or_b_code - 1;
         int range = 1 << bit_size;
         /* modulo encoding */
-        int l= INT_BIT - 5 - bit_size;
-        val= (val<<l)>>l;
+        val = sign_extend(val, 5 + bit_size);
 
         if (val >= 0) {
             val--;