From 724b8f6ac790550caddbf6a7644fba6beb0acf47 Mon Sep 17 00:00:00 2001
From: Justin Ruggles <justin.ruggles@gmail.com>
Date: Mon, 25 May 2009 16:12:51 +0000
Subject: [PATCH] eac3dec: get rid of unnecessary left shifts in 16-bit *
24-bit multiplication in GAQ mantissa ramapping.
Originally committed as revision 18941 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
libavcodec/eac3dec.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/libavcodec/eac3dec.c b/libavcodec/eac3dec.c
index 92d6bdcfd0e..d92d54e3e4f 100644
--- a/libavcodec/eac3dec.c
+++ b/libavcodec/eac3dec.c
@@ -186,13 +186,13 @@ void ff_eac3_decode_transform_coeffs_aht_ch(AC3DecodeContext *s, int ch)
b = 1 << (23 - log_gain);
else
b = ff_eac3_gaq_remap_2_4_b[hebap-8][log_gain-1] << 8;
- mant += (((ff_eac3_gaq_remap_2_4_a[hebap-8][log_gain-1] << 8) * (int64_t)mant) >> 23) + b;
+ mant += ((ff_eac3_gaq_remap_2_4_a[hebap-8][log_gain-1] * (int64_t)mant) >> 15) + b;
} else {
/* small mantissa, no GAQ, or Gk=1 */
mant <<= 24 - bits;
if (!log_gain) {
/* remap mantissa value for no GAQ or Gk=1 */
- mant += ((ff_eac3_gaq_remap_1[hebap-8] << 8) * (int64_t)mant) >> 23;
+ mant += (ff_eac3_gaq_remap_1[hebap-8] * (int64_t)mant) >> 15;
}
}
s->pre_mantissa[ch][bin][blk] = mant;
--
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