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-rw-r--r--thirdparties/win32/include/libavutil/lfg.h62
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diff --git a/thirdparties/win32/include/libavutil/lfg.h b/thirdparties/win32/include/libavutil/lfg.h
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+/*
+ * Lagged Fibonacci PRNG
+ * Copyright (c) 2008 Michael Niedermayer
+ *
+ * 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
+ */
+
+#ifndef AVUTIL_LFG_H
+#define AVUTIL_LFG_H
+
+typedef struct {
+ 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[2] array where the two generated numbers are placed
+ */
+void av_bmg_get(AVLFG *lfg, double out[2]);
+
+#endif /* AVUTIL_LFG_H */
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