From 935fbb66ef325019ee5a64d1efae69282c68d050 Mon Sep 17 00:00:00 2001
From: Justin Ruggles <justin.ruggles@gmail.com>
Date: Sat, 7 Apr 2012 18:55:43 -0400
Subject: [PATCH] wtv: set channel layout for mpeg audio

---
 libavformat/wtv.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/libavformat/wtv.c b/libavformat/wtv.c
index 57d239eb88..7bb421b0ce 100644
--- a/libavformat/wtv.c
+++ b/libavformat/wtv.c
@@ -25,6 +25,7 @@
  * @author Peter Ross <pross@xvid.org>
  */
 
+#include "libavutil/channel_layout.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/intfloat.h"
 #include "libavutil/dict.h"
@@ -618,8 +619,14 @@ static void parse_mpeg1waveformatex(AVStream *st)
 
     /* dwHeadMode */
     switch (AV_RL16(st->codec->extradata + 6)) {
-    case 1 : case 2 : case 4 : st->codec->channels = 2; break;
-    case 8 :                   st->codec->channels = 1; break;
+    case 1 :
+    case 2 :
+    case 4 : st->codec->channels       = 2;
+             st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
+             break;
+    case 8 : st->codec->channels       = 1;
+             st->codec->channel_layout = AV_CH_LAYOUT_MONO;
+             break;
     }
 }