src/clock/clock_internal.h

   1 /*****************************************************************************
   2  * clock_internal.h: Clock internal functions
   3  *****************************************************************************
   4  * Copyright (C) 2018 VLC authors and VideoLAN
   5  *
   6  * Authors: Christophe Massiot <massiot@via.ecp.fr>
   7  *          Laurent Aimar < fenrir _AT_ videolan _DOT_ org >
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #include <vlc_common.h>
  25
  26 /*****************************************************************************
  27  * Structures
  28  *****************************************************************************/
  29
  30 /**
  31  * This structure holds long term moving average
  32  */
  33 typedef struct
  34 {
  35     double value; /* The average value */
  36     int count; /* The number of sample evaluated */
  37     int range; /* The maximum range of sample on which we calculate the average*/
  38 } average_t;
  39
  40 void AvgInit(average_t *, int range);
  41 void AvgClean(average_t *);
  42
  43 void AvgReset(average_t *);
  44
  45 /*  calculates (previous_average * (range - 1) + new_value)/range */
  46 void AvgUpdate(average_t *, double value);
  47
  48 double AvgGet(average_t *);
  49 void AvgRescale(average_t *, int range);
  50
  51 /* */
  52 typedef struct
  53 {
  54     vlc_tick_t system;
  55     vlc_tick_t stream;
  56 } clock_point_t;
  57
  58 static inline clock_point_t clock_point_Create(vlc_tick_t system, vlc_tick_t stream)
  59 {
  60     return (clock_point_t) { .system = system, .stream = stream };
  61 }
  62