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
@@ -0,0 +1,139 @@
+/*
+ * 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