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authorDiego 'Flameeyes' Pettenò <flameeyes@gmail.com>2006-12-02 01:19:48 +0000
committerDiego 'Flameeyes' Pettenò <flameeyes@gmail.com>2006-12-02 01:19:48 +0000
commit0ea721f7ce81357bc4ec6eea609cd50482c3d15b (patch)
tree25a0871cb3c06f9716acf9c204192d548f214048 /contrib/ffmpeg/libavutil/mathematics.c
parentd8ec380876e7f697ba609546d61757ab3f2d8715 (diff)
downloadxine-lib-0ea721f7ce81357bc4ec6eea609cd50482c3d15b.tar.gz
xine-lib-0ea721f7ce81357bc4ec6eea609cd50482c3d15b.tar.bz2
Start working on a branch where FFmpeg is not copied, patched and carved to be built with automake but instead imported inline and built using its own build system. This is an import of a slightly modified FFmpeg current tree. xine-lib builds, install and run fine with it, but there are of course plenty of things that needs to be fixed before it can even be considered for a 1.2.x series. Work will continue in the next days of course.
CVS patchset: 8397 CVS date: 2006/12/02 01:19:48
Diffstat (limited to 'contrib/ffmpeg/libavutil/mathematics.c')
-rw-r--r--contrib/ffmpeg/libavutil/mathematics.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavutil/mathematics.c b/contrib/ffmpeg/libavutil/mathematics.c
new file mode 100644
index 000000000..4be027d9d
--- /dev/null
+++ b/contrib/ffmpeg/libavutil/mathematics.c
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+/*
+ * Copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file mathematics.c
+ * Miscellaneous math routines and tables.
+ */
+
+#include "common.h"
+#include "mathematics.h"
+
+const uint8_t ff_sqrt_tab[128]={
+ 0, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5,
+ 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,11,11,11,11,11,11,11
+};
+
+const uint8_t ff_log2_tab[256]={
+ 0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
+ 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+ 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+ 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7
+};
+
+int64_t ff_gcd(int64_t a, int64_t b){
+ if(b) return ff_gcd(b, a%b);
+ else return a;
+}
+
+int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding rnd){
+ int64_t r=0;
+ assert(c > 0);
+ assert(b >=0);
+ assert(rnd >=0 && rnd<=5 && rnd!=4);
+
+ if(a<0 && a != INT64_MIN) return -av_rescale_rnd(-a, b, c, rnd ^ ((rnd>>1)&1));
+
+ if(rnd==AV_ROUND_NEAR_INF) r= c/2;
+ else if(rnd&1) r= c-1;
+
+ if(b<=INT_MAX && c<=INT_MAX){
+ if(a<=INT_MAX)
+ 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;
+
+ 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)));
+ }
+#endif
+}
+
+int64_t av_rescale(int64_t a, int64_t b, int64_t c){
+ return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
+}
+
+int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){
+ int64_t b= bq.num * (int64_t)cq.den;
+ int64_t c= cq.num * (int64_t)bq.den;
+ return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
+}
+#if 0
+#include "integer.h"
+#undef printf
+main(){
+ int64_t a,b,c,d,e;
+
+ for(a=7; a<(1LL<<62); a+=a/3+1){
+ for(b=3; b<(1LL<<62); b+=b/4+1){
+ for(c=9; c<(1LL<<62); c+=(c*2)/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((double)a * (double)b / (double)c > (1LL<<63))
+ continue;
+
+ if(d!=e) printf("%"PRId64"*%"PRId64"/%"PRId64"= %"PRId64"=%"PRId64"\n", a, b, c, d, e);
+ }
+ }
+ }
+}
+#endif