code.delx.au - pulseaudio/blob - src/pulse/volume.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2004-2006 Lennart Poettering
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2 of the License,
   9   or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <stdio.h>
  27 #include <string.h>
  28
  29 #include <pulsecore/core-util.h>
  30 #include <pulsecore/macro.h>
  31
  32 #include "volume.h"
  33
  34 int pa_cvolume_equal(const pa_cvolume *a, const pa_cvolume *b) {
  35     int i;
  36     pa_assert(a);
  37     pa_assert(b);
  38
  39     if (a->channels != b->channels)
  40         return 0;
  41
  42     for (i = 0; i < a->channels; i++)
  43         if (a->values[i] != b->values[i])
  44             return 0;
  45
  46     return 1;
  47 }
  48
  49 pa_cvolume* pa_cvolume_set(pa_cvolume *a, unsigned channels, pa_volume_t v) {
  50     int i;
  51
  52     pa_assert(a);
  53     pa_assert(channels > 0);
  54     pa_assert(channels <= PA_CHANNELS_MAX);
  55
  56     a->channels = (uint8_t) channels;
  57
  58     for (i = 0; i < a->channels; i++)
  59         a->values[i] = v;
  60
  61     return a;
  62 }
  63
  64 pa_volume_t pa_cvolume_avg(const pa_cvolume *a) {
  65     uint64_t sum = 0;
  66     int i;
  67     pa_assert(a);
  68
  69     for (i = 0; i < a->channels; i++)
  70         sum += a->values[i];
  71
  72     sum /= a->channels;
  73
  74     return (pa_volume_t) sum;
  75 }
  76
  77 pa_volume_t pa_cvolume_max(const pa_cvolume *a) {
  78     pa_volume_t m = 0;
  79     int i;
  80     pa_assert(a);
  81
  82     for (i = 0; i < a->channels; i++)
  83         if (a->values[i] > m)
  84             m = a->values[i];
  85
  86     return m;
  87 }
  88
  89 pa_volume_t pa_sw_volume_multiply(pa_volume_t a, pa_volume_t b) {
  90     return pa_sw_volume_from_linear(pa_sw_volume_to_linear(a)* pa_sw_volume_to_linear(b));
  91 }
  92
  93 #define USER_DECIBEL_RANGE 60
  94
  95 pa_volume_t pa_sw_volume_from_dB(double dB) {
  96     if (isinf(dB) < 0 || dB <= -USER_DECIBEL_RANGE)
  97         return PA_VOLUME_MUTED;
  98
  99     return (pa_volume_t) ((dB/USER_DECIBEL_RANGE+1)*PA_VOLUME_NORM);
 100 }
 101
 102 double pa_sw_volume_to_dB(pa_volume_t v) {
 103     if (v == PA_VOLUME_MUTED)
 104         return PA_DECIBEL_MININFTY;
 105
 106     return ((double) v/PA_VOLUME_NORM-1)*USER_DECIBEL_RANGE;
 107 }
 108
 109 pa_volume_t pa_sw_volume_from_linear(double v) {
 110
 111     if (v <= 0)
 112         return PA_VOLUME_MUTED;
 113
 114     if (v > .999 && v < 1.001)
 115         return PA_VOLUME_NORM;
 116
 117     return pa_sw_volume_from_dB(20*log10(v));
 118 }
 119
 120 double pa_sw_volume_to_linear(pa_volume_t v) {
 121
 122     if (v == PA_VOLUME_MUTED)
 123         return 0;
 124
 125     return pow(10, pa_sw_volume_to_dB(v)/20);
 126 }
 127
 128 char *pa_cvolume_snprint(char *s, size_t l, const pa_cvolume *c) {
 129     unsigned channel;
 130     int first = 1;
 131     char *e;
 132
 133     pa_assert(s);
 134     pa_assert(l > 0);
 135     pa_assert(c);
 136
 137     *(e = s) = 0;
 138
 139     for (channel = 0; channel < c->channels && l > 1; channel++) {
 140         l -= pa_snprintf(e, l, "%s%u: %3u%%",
 141                       first ? "" : " ",
 142                       channel,
 143                       (c->values[channel]*100)/PA_VOLUME_NORM);
 144
 145         e = strchr(e, 0);
 146         first = 0;
 147     }
 148
 149     return s;
 150 }
 151
 152 /** Return non-zero if the volume of all channels is equal to the specified value */
 153 int pa_cvolume_channels_equal_to(const pa_cvolume *a, pa_volume_t v) {
 154     unsigned c;
 155     pa_assert(a);
 156
 157     for (c = 0; c < a->channels; c++)
 158         if (a->values[c] != v)
 159             return 0;
 160
 161     return 1;
 162 }
 163
 164 pa_cvolume *pa_sw_cvolume_multiply(pa_cvolume *dest, const pa_cvolume *a, const pa_cvolume *b) {
 165     unsigned i;
 166
 167     pa_assert(dest);
 168     pa_assert(a);
 169     pa_assert(b);
 170
 171     for (i = 0; i < a->channels && i < b->channels && i < PA_CHANNELS_MAX; i++) {
 172
 173         dest->values[i] = pa_sw_volume_multiply(
 174             i < a->channels ? a->values[i] : PA_VOLUME_NORM,
 175             i < b->channels ? b->values[i] : PA_VOLUME_NORM);
 176     }
 177
 178     dest->channels = (uint8_t) i;
 179
 180     return dest;
 181 }
 182
 183 int pa_cvolume_valid(const pa_cvolume *v) {
 184     pa_assert(v);
 185
 186     if (v->channels <= 0 || v->channels > PA_CHANNELS_MAX)
 187         return 0;
 188
 189     return 1;
 190 }
 191
 192 static pa_bool_t on_left(pa_channel_position_t p) {
 193
 194     return
 195         p == PA_CHANNEL_POSITION_FRONT_LEFT ||
 196         p == PA_CHANNEL_POSITION_REAR_LEFT ||
 197         p == PA_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER ||
 198         p == PA_CHANNEL_POSITION_SIDE_LEFT ||
 199         p == PA_CHANNEL_POSITION_TOP_FRONT_LEFT ||
 200         p == PA_CHANNEL_POSITION_TOP_REAR_LEFT;
 201 }
 202
 203 static pa_bool_t on_right(pa_channel_position_t p) {
 204
 205     return
 206         p == PA_CHANNEL_POSITION_FRONT_RIGHT ||
 207         p == PA_CHANNEL_POSITION_REAR_RIGHT ||
 208         p == PA_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER ||
 209         p == PA_CHANNEL_POSITION_SIDE_RIGHT ||
 210         p == PA_CHANNEL_POSITION_TOP_FRONT_RIGHT ||
 211         p == PA_CHANNEL_POSITION_TOP_REAR_RIGHT;
 212 }
 213
 214 static pa_bool_t on_center(pa_channel_position_t p) {
 215
 216     return
 217         p == PA_CHANNEL_POSITION_FRONT_CENTER ||
 218         p == PA_CHANNEL_POSITION_REAR_CENTER ||
 219         p == PA_CHANNEL_POSITION_TOP_CENTER ||
 220         p == PA_CHANNEL_POSITION_TOP_FRONT_CENTER ||
 221         p == PA_CHANNEL_POSITION_TOP_REAR_CENTER;
 222 }
 223
 224 static pa_bool_t on_lfe(pa_channel_position_t p) {
 225     return
 226         p == PA_CHANNEL_POSITION_LFE;
 227 }
 228
 229 pa_cvolume *pa_cvolume_remap(pa_cvolume *v, pa_channel_map *from, pa_channel_map *to) {
 230     int a, b;
 231     pa_cvolume result;
 232
 233     pa_assert(v);
 234     pa_assert(from);
 235     pa_assert(to);
 236     pa_assert(v->channels == from->channels);
 237
 238     if (pa_channel_map_equal(from, to))
 239         return v;
 240
 241     result.channels = to->channels;
 242
 243     for (b = 0; b < to->channels; b++) {
 244         pa_volume_t k = 0;
 245         int n = 0;
 246
 247         for (a = 0; a < from->channels; a++)
 248             if (from->map[a] == to->map[b]) {
 249                 k += v->values[a];
 250                 n ++;
 251             }
 252
 253         if (n <= 0) {
 254             for (a = 0; a < from->channels; a++)
 255                 if ((on_left(from->map[a]) && on_left(to->map[b])) ||
 256                     (on_right(from->map[a]) && on_right(to->map[b])) ||
 257                     (on_center(from->map[a]) && on_center(to->map[b])) ||
 258                     (on_lfe(from->map[a]) && on_lfe(to->map[b]))) {
 259
 260                     k += v->values[a];
 261                     n ++;
 262                 }
 263         }
 264
 265         if (n <= 0)
 266             k = pa_cvolume_avg(v);
 267         else
 268             k /= n;
 269
 270         result.values[b] = k;
 271     }
 272
 273     *v = result;
 274     return v;
 275 }