src/replay_gain_info.h

   1 /*
   2  * Copyright (C) 2003-2010 The Music Player Daemon Project
   3  * http://www.musicpd.org
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #ifndef MPD_REPLAY_GAIN_INFO_H
  21 #define MPD_REPLAY_GAIN_INFO_H
  22
  23 #include "check.h"
  24
  25 #include <stdbool.h>
  26 #include <math.h>
  27
  28 enum replay_gain_mode {
  29         REPLAY_GAIN_OFF = -1,
  30         REPLAY_GAIN_ALBUM,
  31         REPLAY_GAIN_TRACK,
  32 };
  33
  34 struct replay_gain_tuple {
  35         float gain;
  36         float peak;
  37 };
  38
  39 struct replay_gain_info {
  40         struct replay_gain_tuple tuples[2];
  41 };
  42
  43 static inline void
  44 replay_gain_tuple_init(struct replay_gain_tuple *tuple)
  45 {
  46         tuple->gain = INFINITY;
  47         tuple->peak = 0.0;
  48 }
  49
  50 static inline void
  51 replay_gain_info_init(struct replay_gain_info *info)
  52 {
  53         replay_gain_tuple_init(&info->tuples[REPLAY_GAIN_ALBUM]);
  54         replay_gain_tuple_init(&info->tuples[REPLAY_GAIN_TRACK]);
  55 }
  56
  57 static inline bool
  58 replay_gain_tuple_defined(const struct replay_gain_tuple *tuple)
  59 {
  60         return !isinf(tuple->gain);
  61 }
  62
  63 float
  64 replay_gain_tuple_scale(const struct replay_gain_tuple *tuple, float preamp);
  65
  66 /**
  67  * Attempt to auto-complete missing data.  In particular, if album
  68  * information is missing, track gain is used.
  69  */
  70 void
  71 replay_gain_info_complete(struct replay_gain_info *info);
  72
  73 #endif