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avoid AVInteger usage in av_rescale

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disable integer.* (unused)
libavutil.a 45k -> 32k

Originally committed as revision 5311 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2006-04-23 10:28:54 +00:00
parent 176c142abc
commit fdb3a34156
2 changed files with 54 additions and 7 deletions
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1
libavutil/Makefile
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@ -12,7 +12,6 @@ ifeq ($(CONFIG_WIN32),yes)
endif endif
OBJS= mathematics.o \ OBJS= mathematics.o \
integer.o \
rational.o \ rational.o \
intfloat_readwrite.o \ intfloat_readwrite.o \
crc.o \ crc.o \

54
libavutil/mathematics.c
View File

@ -22,7 +22,6 @@
*/ */
#include "common.h" #include "common.h"
#include "integer.h"
#include "mathematics.h" #include "mathematics.h"
const uint8_t ff_sqrt_tab[128]={ const uint8_t ff_sqrt_tab[128]={
@ -49,7 +48,6 @@ int64_t ff_gcd(int64_t a, int64_t b){
} }
int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding rnd){ int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding rnd){
AVInteger ai;
int64_t r=0; int64_t r=0;
assert(c > 0); assert(c > 0);
assert(b >=0); assert(b >=0);
@ -65,13 +63,41 @@ int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding rnd){
return (a * b + r)/c; return (a * b + r)/c;
else else
return a/c*b + (a%c*b + r)/c; return a/c*b + (a%c*b + r)/c;
} }else{
#if 1
uint64_t a0= a&0xFFFFFFFF;
uint64_t a1= a>>32;
uint64_t b0= b&0xFFFFFFFF;
uint64_t b1= b>>32;
uint64_t t1= a0*b1 + a1*b0;
uint64_t t1a= t1<<32;
int i;
a0 = a0*b0 + t1a;
a1 = a1*b1 + (t1>>32) + (a0<t1a);
a0 += r;
a1 += a0<r;
for(i=63; i>=0; i--){
// int o= a1 & 0x8000000000000000ULL;
a1+= a1 + ((a0>>i)&1);
t1+=t1;
if(/*o || */c >= a1){
a1 -= c;
t1++;
}
}
return t1;
}
#else
AVInteger ai;
ai= av_mul_i(av_int2i(a), av_int2i(b)); ai= av_mul_i(av_int2i(a), av_int2i(b));
ai= av_add_i(ai, av_int2i(r)); ai= av_add_i(ai, av_int2i(r));
return av_i2int(av_div_i(ai, av_int2i(c))); return av_i2int(av_div_i(ai, av_int2i(c)));
} }
#endif
}
int64_t av_rescale(int64_t a, int64_t b, int64_t c){ int64_t av_rescale(int64_t a, int64_t b, int64_t c){
return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF); return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
@ -82,3 +108,25 @@ int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){
int64_t c= cq.num * (int64_t)bq.den; int64_t c= cq.num * (int64_t)bq.den;
return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF); return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
} }
#if 0
main(){
int64_t a,b,c,d,e;
for(a=7; a<256*256*256*128LL; a=(a*3)+1){
for(b=3; b<256*256*256*128LL; b=(b*5)/4+1){
for(c=9; c<256*256*256*128LL; c=(c*7)/5+3 ){
int64_t r= c/2;
AVInteger ai;
ai= av_mul_i(av_int2i(a), av_int2i(b));
ai= av_add_i(ai, av_int2i(r));
d= av_i2int(av_div_i(ai, av_int2i(c)));
e= av_rescale(a,b,c);
if(d!=e) printf("%Ld*%Ld/%Ld= %Ld=%Ld\n"L, a, b, c, d, e);
}
}
}
}
#endif