lavc: add Intel libmfx-based MPEG2 decoder.

[ffmpeg] / libavutil / lfg.h

diff --git a/libavutil/lfg.h b/libavutil/lfg.h
index 3250c18e794295e6dd4575b913e70fecd9a3822e..5e526c1dae21e745d527bda9ed800e25490818ab 100644 (file)
--- a/libavutil/lfg.h
+++ b/libavutil/lfg.h
@@ -2,27 +2,27 @@
  * Lagged Fibonacci PRNG
  * Copyright (c) 2008 Michael Niedermayer
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * 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.
  *
- * FFmpeg is distributed in the hope that it will be useful,
+ * 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 FFmpeg; if not, write to the Free Software
+ * 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 {
+typedef struct AVLFG {
     unsigned int state[64];
     int index;
 } AVLFG;
@@ -30,7 +30,7 @@ typedef struct {
 void av_lfg_init(AVLFG *c, unsigned int seed);
 
 /**
- * Gets the next random unsigned 32-bit number using an ALFG.
+ * 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.
@@ -41,7 +41,7 @@ static inline unsigned int av_lfg_get(AVLFG *c){
 }
 
 /**
- * Gets the next random unsigned 32-bit number using a MLFG.
+ * Get the next random unsigned 32-bit number using a MLFG.
  *
  * Please also consider av_lfg_get() above, it is faster.
  */
@@ -51,4 +51,12 @@ static inline unsigned int av_mlfg_get(AVLFG *c){
     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 */