1 files changed, 145 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavutil/mathematics.c b/contrib/ffmpeg/libavutil/mathematics.c
new file mode 100644
index 000000000..ef93ba4a1
--- /dev/null
+++ b/contrib/ffmpeg/libavutil/mathematics.c
@@ -0,0 +1,145 @@
+/*
+ * 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[256]={
+  0, 16, 23, 28, 32, 36, 40, 43, 46, 48, 51, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 77, 79, 80, 82, 84, 85, 87, 88, 90,
+ 91, 92, 94, 95, 96, 98, 99,100,102,103,104,105,107,108,109,110,111,112,114,115,116,117,118,119,120,121,122,123,124,125,126,127,
+128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,144,145,146,147,148,149,150,151,151,152,153,154,155,156,156,
+157,158,159,160,160,161,162,163,164,164,165,166,167,168,168,169,170,171,171,172,173,174,174,175,176,176,177,178,179,179,180,181,
+182,182,183,184,184,185,186,186,187,188,188,189,190,190,191,192,192,193,194,194,195,196,196,197,198,198,199,200,200,201,202,202,
+203,204,204,205,205,206,207,207,208,208,209,210,210,211,212,212,213,213,214,215,215,216,216,217,218,218,219,219,220,220,221,222,
+222,223,223,224,224,225,226,226,227,227,228,228,229,230,230,231,231,232,232,233,233,234,235,235,236,236,237,237,238,238,239,239,
+240,240,241,242,242,243,243,244,244,245,245,246,246,247,247,248,248,249,249,250,250,251,251,252,252,253,253,254,254,255,255,255
+};
+
+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);
+}
+
+#ifdef TEST
+#include "integer.h"
+#undef printf
+int main(void){
+    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);
+            }
+        }
+    }
+    return 0;
+}
+#endif