diff -r 90a79670de52 -r 262003f2e19a misc/winutils/include/libavutil/lfg.h --- a/misc/winutils/include/libavutil/lfg.h Sat Aug 31 22:30:29 2019 +0300 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,62 +0,0 @@ -/* - * Lagged Fibonacci PRNG - * Copyright (c) 2008 Michael Niedermayer - * - * This file is part of Libav. - * - * Libav 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. - * - * Libav 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 Libav; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#ifndef AVUTIL_LFG_H -#define AVUTIL_LFG_H - -typedef struct AVLFG { - unsigned int state[64]; - int index; -} AVLFG; - -void av_lfg_init(AVLFG *c, unsigned int seed); - -/** - * Get the next random unsigned 32-bit number using an ALFG. - * - * Please also consider a simple LCG like state= state*1664525+1013904223, - * it may be good enough and faster for your specific use case. - */ -static inline unsigned int av_lfg_get(AVLFG *c){ - c->state[c->index & 63] = c->state[(c->index-24) & 63] + c->state[(c->index-55) & 63]; - return c->state[c->index++ & 63]; -} - -/** - * Get the next random unsigned 32-bit number using a MLFG. - * - * Please also consider av_lfg_get() above, it is faster. - */ -static inline unsigned int av_mlfg_get(AVLFG *c){ - unsigned int a= c->state[(c->index-55) & 63]; - unsigned int b= c->state[(c->index-24) & 63]; - return c->state[c->index++ & 63] = 2*a*b+a+b; -} - -/** - * Get the next two numbers generated by a Box-Muller Gaussian - * generator using the random numbers issued by lfg. - * - * @param out array where the two generated numbers are placed - */ -void av_bmg_get(AVLFG *lfg, double out[2]); - -#endif /* AVUTIL_LFG_H */