[FFmpeg-devel] [PATCH] mdct: remove unnecessary multiplication

Young Han Lee cpumaker
Thu Feb 17 08:45:54 CET 2011


3*n4 was already calculated in n3.

---
 libavcodec/mdct.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/libavcodec/mdct.c b/libavcodec/mdct.c
index 819f618..31e2216 100644
--- a/libavcodec/mdct.c
+++ b/libavcodec/mdct.c
@@ -202,7 +202,7 @@ void ff_mdct_calc_c(FFTContext *s, FFTSample *out, const
FFTSample *input)

     /* pre rotation */
     for(i=0;i<n8;i++) {
-        re = -input[2*i+3*n4] - input[n3-1-2*i];
+        re = -input[2*i+n3] - input[n3-1-2*i];
         im = -input[n4+2*i] + input[n4-1-2*i];
         j = revtab[i];
         CMUL(x[j].re, x[j].im, re, im, -tcos[i], tsin[i]);
-- 
1.7.1



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