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optimization

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Originally committed as revision 3616 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2004-10-20 19:06:29 +00:00
parent 51a880208a
commit f25ba8b393
1 changed files with 4 additions and 4 deletions
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8
libavcodec/resample2.c
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@ -42,7 +42,7 @@
#define FELEM_MAX INT16_MAX #define FELEM_MAX INT16_MAX
#define FELEM_MIN INT16_MIN #define FELEM_MIN INT16_MIN
#else #else
#define FILTER_SHIFT 24 #define FILTER_SHIFT 22
#define FELEM int32_t #define FELEM int32_t
#define FELEM2 int64_t #define FELEM2 int64_t
@ -193,12 +193,12 @@ int av_resample(AVResampleContext *c, short *dst, short *src, int *consumed, int
}else{ }else{
#ifdef LINEAR #ifdef LINEAR
int64_t v=0; 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++){ 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; v += src[sample_index + i] * coeff;
} }
val= v>>12; val= v>>8;
#else #else
for(i=0; i<c->filter_length; i++){ for(i=0; i<c->filter_length; i++){
val += src[sample_index + i] * (FELEM2)filter[i]; val += src[sample_index + i] * (FELEM2)filter[i];