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authorMichael Niedermayer <michaelni@gmx.at>2006-04-23 10:28:54 +0000
committerMichael Niedermayer <michaelni@gmx.at>2006-04-23 10:28:54 +0000
commitfdb3a3415688efdc1e03b43c7ed6f6bcb95da3e5 (patch)
tree44446b05d697101465bd4f7cdb0793a9743e55d8 /libavutil/mathematics.c
parent176c142abcbfda1cc161ca8614ab07dffe505349 (diff)
downloadffmpeg-fdb3a3415688efdc1e03b43c7ed6f6bcb95da3e5.tar.gz
avoid AVInteger usage in av_rescale
disable integer.* (unused) libavutil.a 45k -> 32k Originally committed as revision 5311 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavutil/mathematics.c')
-rw-r--r--libavutil/mathematics.c60
1 files changed, 54 insertions, 6 deletions
diff --git a/libavutil/mathematics.c b/libavutil/mathematics.c
index 3cd47a8ac0..54698b7ab1 100644
--- a/libavutil/mathematics.c
+++ b/libavutil/mathematics.c
@@ -22,7 +22,6 @@
*/
#include "common.h"
-#include "integer.h"
#include "mathematics.h"
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){
- AVInteger ai;
int64_t r=0;
assert(c > 0);
assert(b >=0);
@@ -65,12 +63,40 @@ int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding rnd){
return (a * b + r)/c;
else
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;
- ai= av_mul_i(av_int2i(a), av_int2i(b));
- ai= av_add_i(ai, av_int2i(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_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){
@@ -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;
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 \ No newline at end of file