src/audio_output/volume.c

   1 /*****************************************************************************
   2  * volume.c : audio output volume operations
   3  *****************************************************************************
   4  * Copyright (C) 2002-2004 VLC authors and VideoLAN
   5  * Copyright (C) 2011-2012 Rémi Denis-Courmont
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU Lesser General Public License as published by
   9  * the Free Software Foundation; either version 2.1 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public License
  18  * along with this program; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  20  *****************************************************************************/
  21
  22 #ifdef HAVE_CONFIG_H
  23 # include "config.h"
  24 #endif
  25
  26 #include <stddef.h>
  27 #include <math.h>
  28
  29 #include <vlc_common.h>
  30 #include <libvlc.h>
  31 #include <vlc_modules.h>
  32 #include <vlc_aout.h>
  33 #include <vlc_aout_volume.h>
  34 #include "aout_internal.h"
  35
  36 struct aout_volume
  37 {
  38     audio_volume_t object;
  39     audio_replay_gain_t replay_gain;
  40     vlc_atomic_float gain_factor;
  41     float output_factor;
  42     module_t *module;
  43 };
  44
  45 static int ReplayGainCallback (vlc_object_t *, char const *,
  46                                vlc_value_t, vlc_value_t, void *);
  47
  48 #undef aout_volume_New
  49 /**
  50  * Creates a software amplifier.
  51  */
  52 aout_volume_t *aout_volume_New(vlc_object_t *parent,
  53                                const audio_replay_gain_t *gain)
  54 {
  55     aout_volume_t *vol = vlc_custom_create(parent, sizeof (aout_volume_t),
  56                                            "volume");
  57     if (unlikely(vol == NULL))
  58         return NULL;
  59     vol->module = NULL;
  60     vol->output_factor = 1.f;
  61
  62     //audio_volume_t *obj = &vol->object;
  63
  64     /* Gain */
  65     if (gain != NULL)
  66         memcpy(&vol->replay_gain, gain, sizeof (vol->replay_gain));
  67     else
  68         memset(&vol->replay_gain, 0, sizeof (vol->replay_gain));
  69
  70     var_AddCallback(parent, "audio-replay-gain-mode",
  71                     ReplayGainCallback, vol);
  72     var_TriggerCallback(parent, "audio-replay-gain-mode");
  73
  74     return vol;
  75 }
  76
  77 /**
  78  * Selects the current sample format for software amplification.
  79  */
  80 int aout_volume_SetFormat(aout_volume_t *vol, vlc_fourcc_t format)
  81 {
  82     if (unlikely(vol == NULL))
  83         return -1;
  84
  85     audio_volume_t *obj = &vol->object;
  86     if (vol->module != NULL)
  87     {
  88         if (obj->format == format)
  89         {
  90             msg_Dbg (obj, "retaining sample format");
  91             return 0;
  92         }
  93         msg_Dbg (obj, "changing sample format");
  94         module_unneed(obj, vol->module);
  95     }
  96
  97     obj->format = format;
  98     vol->module = module_need(obj, "audio volume", NULL, false);
  99     if (vol->module == NULL)
 100         return -1;
 101     return 0;
 102 }
 103
 104 /**
 105  * Destroys a software amplifier.
 106  */
 107 void aout_volume_Delete(aout_volume_t *vol)
 108 {
 109     if (vol == NULL)
 110         return;
 111
 112     audio_volume_t *obj = &vol->object;
 113
 114     if (vol->module != NULL)
 115         module_unneed(obj, vol->module);
 116     var_DelCallback(obj->p_parent, "audio-replay-gain-mode",
 117                     ReplayGainCallback, vol);
 118     vlc_object_release(obj);
 119 }
 120
 121 void aout_volume_SetVolume(aout_volume_t *vol, float factor)
 122 {
 123     if (unlikely(vol == NULL))
 124         return;
 125
 126     vol->output_factor = factor;
 127 }
 128
 129 /**
 130  * Applies replay gain and software volume to an audio buffer.
 131  */
 132 int aout_volume_Amplify(aout_volume_t *vol, block_t *block)
 133 {
 134     if (unlikely(vol == NULL) || vol->module == NULL)
 135         return -1;
 136
 137     float amp = vol->output_factor
 138               * vlc_atomic_loadf (&vol->gain_factor);
 139
 140     vol->object.amplify(&vol->object, block, amp);
 141     return 0;
 142 }
 143
 144 /*** Replay gain ***/
 145 static float aout_ReplayGainSelect(vlc_object_t *obj, const char *str,
 146                                    const audio_replay_gain_t *replay_gain)
 147 {
 148     unsigned mode = AUDIO_REPLAY_GAIN_MAX;
 149
 150     if (likely(str != NULL))
 151     {   /* Find selectrf mode */
 152         if (!strcmp (str, "track"))
 153             mode = AUDIO_REPLAY_GAIN_TRACK;
 154         else
 155         if (!strcmp (str, "album"))
 156             mode = AUDIO_REPLAY_GAIN_ALBUM;
 157     }
 158
 159     /* */
 160     float multiplier;
 161
 162     if (mode == AUDIO_REPLAY_GAIN_MAX)
 163     {
 164         multiplier = 1.f;
 165     }
 166     else
 167     {
 168         float gain;
 169
 170         /* If the selectrf mode is not available, prefer the other one */
 171         if (!replay_gain->pb_gain[mode] && replay_gain->pb_gain[!mode])
 172             mode = !mode;
 173
 174         if (replay_gain->pb_gain[mode])
 175             gain = replay_gain->pf_gain[mode]
 176                  + var_InheritFloat (obj, "audio-replay-gain-preamp");
 177         else
 178             gain = var_InheritFloat (obj, "audio-replay-gain-default");
 179
 180         multiplier = pow (10., gain / 20.);
 181
 182         if (var_InheritBool (obj, "audio-replay-gain-peak-protection"))
 183             multiplier = fminf (multiplier, replay_gain->pb_peak[mode]
 184                                             ? 1.f / replay_gain->pf_peak[mode]
 185                                             : 1.f);
 186     }
 187
 188     /* Command line / configuration gain */
 189     multiplier *= var_InheritFloat (obj, "gain");
 190
 191     return multiplier;
 192 }
 193
 194 static int ReplayGainCallback (vlc_object_t *obj, char const *var,
 195                                vlc_value_t oldval, vlc_value_t val, void *data)
 196 {
 197     aout_volume_t *vol = data;
 198     float multiplier = aout_ReplayGainSelect(obj, val.psz_string,
 199                                              &vol->replay_gain);
 200     vlc_atomic_storef (&vol->gain_factor, multiplier);
 201     VLC_UNUSED(var); VLC_UNUSED(oldval);
 202     return VLC_SUCCESS;
 203 }