From 3d5e1bfb20d3489d7bb2fa26196e02086e06f2b8 Mon Sep 17 00:00:00 2001
From: Jai Menon <realityman@gmx.net>
Date: Fri, 5 Dec 2008 07:58:31 +0000
Subject: [PATCH] Fix an overflow in the predictor. fixes issue 636 Patch by
 Jai.

Originally committed as revision 16007 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavcodec/alacenc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libavcodec/alacenc.c b/libavcodec/alacenc.c
index df4136f4c4..9fd5064514 100644
--- a/libavcodec/alacenc.c
+++ b/libavcodec/alacenc.c
@@ -253,7 +253,8 @@ static void alac_linear_predictor(AlacEncodeContext *s, int ch)
 
             sum >>= lpc.lpc_quant;
             sum += samples[0];
-            residual[i] = samples[lpc.lpc_order+1] - sum;
+            residual[i] = (samples[lpc.lpc_order+1] - sum) << (32 - s->write_sample_size) >>
+                          (32 - s->write_sample_size);
             res_val = residual[i];
 
             if(res_val) {