From f25ba8b39380d3bbe1b58b6422062427d19b787c Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Wed, 20 Oct 2004 19:06:29 +0000
Subject: [PATCH] optimization
Originally committed as revision 3616 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
libavcodec/resample2.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/libavcodec/resample2.c b/libavcodec/resample2.c
index ad303a44981..22f787dc166 100644
--- a/libavcodec/resample2.c
+++ b/libavcodec/resample2.c
@@ -42,7 +42,7 @@
#define FELEM_MAX INT16_MAX
#define FELEM_MIN INT16_MIN
#else
-#define FILTER_SHIFT 24
+#define FILTER_SHIFT 22
#define FELEM int32_t
#define FELEM2 int64_t
@@ -193,12 +193,12 @@ int av_resample(AVResampleContext *c, short *dst, short *src, int *consumed, int
}else{
#ifdef LINEAR
int64_t v=0;
- int sub_phase= (frac<<12) / c->src_incr;
+ int sub_phase= (frac<<8) / c->src_incr;
for(i=0; i<c->filter_length; i++){
- int64_t coeff= filter[i]*(FELEM2)(4096 - sub_phase) + filter[i + c->filter_length]*(FELEM2)sub_phase;
+ int64_t coeff= filter[i]*(256 - sub_phase) + filter[i + c->filter_length]*sub_phase;
v += src[sample_index + i] * coeff;
}
- val= v>>12;
+ val= v>>8;
#else
for(i=0; i<c->filter_length; i++){
val += src[sample_index + i] * (FELEM2)filter[i];
--
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