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authorSven Gothel <[email protected]>2013-08-25 09:06:11 +0200
committerSven Gothel <[email protected]>2013-08-25 09:06:11 +0200
commit640dbb2e1780a6074b932a455252bb410e4393de (patch)
tree720da42ece2392cf734a1e48fe053e7bf558cf20 /make/stub_includes/libav/lavc53.lavf53.lavu51/libavutil/lfg.h
parentd0aee05031cd52ad4f6753a8859a21e77845bc35 (diff)
libav/ffmpeg: Move current lavc53.lavf53.lavu51 (version 8) header files to their sub-folders; Add lavc54.lavf54.lavu52 (version 9) header files
lavc54.lavf54.lavu52: - Begin testing w/ version 9 - Header files are binary incompatible (data types) Default is still lavc53.lavf53.lavu51
Diffstat (limited to 'make/stub_includes/libav/lavc53.lavf53.lavu51/libavutil/lfg.h')
-rw-r--r--make/stub_includes/libav/lavc53.lavf53.lavu51/libavutil/lfg.h62
1 files changed, 62 insertions, 0 deletions
diff --git a/make/stub_includes/libav/lavc53.lavf53.lavu51/libavutil/lfg.h b/make/stub_includes/libav/lavc53.lavf53.lavu51/libavutil/lfg.h
new file mode 100644
index 000000000..904d00a66
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+++ b/make/stub_includes/libav/lavc53.lavf53.lavu51/libavutil/lfg.h
@@ -0,0 +1,62 @@
+/*
+ * 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 {
+ 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 */