From 7988dd1b9a1a5013a77d90cb7105c8a83d836756 Mon Sep 17 00:00:00 2001
From: Carl Eugen Hoyos <cehoyos@ag.or.at>
Date: Wed, 25 Jan 2012 03:51:49 +0100
Subject: Fix multi-channel encoding with libfaac.

---
 libavcodec/libfaac.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

(limited to 'libavcodec')

diff --git a/libavcodec/libfaac.c b/libavcodec/libfaac.c
index 4758cf7462..31dc1a41ed 100644
--- a/libavcodec/libfaac.c
+++ b/libavcodec/libfaac.c
@@ -31,6 +31,13 @@ typedef struct FaacAudioContext {
     faacEncHandle faac_handle;
 } FaacAudioContext;
 
+static const int channel_maps[][6] = {
+    { 2, 0, 1 },          //< C L R
+    { 2, 0, 1, 3 },       //< C L R Cs
+    { 2, 0, 1, 3, 4 },    //< C L R Ls Rs
+    { 2, 0, 1, 4, 5, 3 }, //< C L R Ls Rs LFE
+};
+
 static av_cold int Faac_encode_init(AVCodecContext *avctx)
 {
     FaacAudioContext *s = avctx->priv_data;
@@ -86,6 +93,9 @@ static av_cold int Faac_encode_init(AVCodecContext *avctx)
     }
     faac_cfg->outputFormat = 1;
     faac_cfg->inputFormat = FAAC_INPUT_16BIT;
+    if (avctx->channels > 2)
+        memcpy(faac_cfg->channel_map, channel_maps[avctx->channels-3],
+               avctx->channels * sizeof(int));
 
     avctx->frame_size = samples_input / avctx->channels;
 
-- 
cgit v1.2.3