From 5fa82264201c3bcd09615c5983496983b4012566 Mon Sep 17 00:00:00 2001
From: Pavel Koshevoy <pkoshevoy@gmail.com>
Date: Sun, 17 Jun 2012 16:45:26 -0600
Subject: [PATCH] libavfilter: improve atempo audio quality

Reduce audio fragment alignment jitter by penalizing alignment
correction offsets that deviate too much from the target offset.
This is accomplished by multiplying the cross correlation search
window with a quadratic function.

Signed-off-by: Pavel Koshevoy <pavel@homestead.aragog.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
---
 libavfilter/af_atempo.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavfilter/af_atempo.c b/libavfilter/af_atempo.c
index 1ccc3f5629..92390cf217 100644
--- a/libavfilter/af_atempo.c
+++ b/libavfilter/af_atempo.c
@@ -654,7 +654,7 @@ static int yae_align(AudioFragment *frag,
 
         // normalize:
         FFTSample drifti = (FFTSample)(drift + i);
-        metric *= drifti;
+        metric *= drifti * (FFTSample)(i - i0) * (FFTSample)(i1 - i);
 
         if (metric > best_metric) {
             best_metric = metric;