modules/audio_output/amem.c

   1 /*****************************************************************************
   2  * amem.c : virtual LibVLC audio output plugin
   3  *****************************************************************************
   4  * Copyright (C) 2011 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 #include <vlc_common.h>
  26 #include <vlc_plugin.h>
  27 #include <vlc_aout.h>
  28 #include <assert.h>
  29
  30 static int Open (vlc_object_t *);
  31 static void Close (vlc_object_t *);
  32
  33 vlc_module_begin ()
  34     set_shortname (N_("Audio memory"))
  35     set_description (N_("Audio memory output"))
  36     set_capability ("audio output", 0)
  37     set_category (CAT_AUDIO)
  38     set_subcategory (SUBCAT_AUDIO_AOUT)
  39     set_callbacks (Open, Close)
  40
  41     add_string ("amem-format", "S16N",
  42                 N_("Sample format"), N_("Sample format"), false)
  43         change_private()
  44     add_integer ("amem-rate", 44100,
  45                  N_("Sample rate"), N_("Sample rate"), false)
  46         change_integer_range (1, 352800)
  47         change_private()
  48     add_integer ("amem-channels", 2,
  49                  N_("Channels count"), N_("Channels count"), false)
  50         change_integer_range (1, AOUT_CHAN_MAX)
  51         change_private()
  52
  53 vlc_module_end ()
  54
  55 struct aout_sys_t
  56 {
  57     void *opaque;
  58     int (*setup) (void **, char *, unsigned *, unsigned *);
  59     void (*cleanup) (void *opaque);
  60     union
  61     {
  62         struct
  63         {
  64             void *setup_opaque;
  65         };
  66         struct
  67         {
  68              unsigned rate:18;
  69              unsigned channels:14;
  70         };
  71     };
  72     void (*play) (void *opaque, const void *data, unsigned count, int64_t pts);
  73     void (*pause) (void *opaque, int64_t pts);
  74     void (*resume) (void *opaque, int64_t pts);
  75     void (*flush) (void *opaque);
  76     void (*drain) (void *opaque);
  77     int (*set_volume) (void *opaque, float vol, bool mute);
  78     float volume;
  79     bool mute;
  80     bool ready;
  81 };
  82
  83 static void Play (audio_output_t *aout, block_t *block)
  84 {
  85     aout_sys_t *sys = aout->sys;
  86
  87     sys->play (sys->opaque, block->p_buffer, block->i_nb_samples,
  88                block->i_pts);
  89     block_Release (block);
  90 }
  91
  92 static void Pause (audio_output_t *aout, bool paused, mtime_t date)
  93 {
  94     aout_sys_t *sys = aout->sys;
  95     void (*cb) (void *, int64_t) = paused ? sys->pause : sys->resume;
  96
  97     if (cb != NULL)
  98         cb (sys->opaque, date);
  99 }
 100
 101 static void Flush (audio_output_t *aout, bool wait)
 102 {
 103     aout_sys_t *sys = aout->sys;
 104     void (*cb) (void *) = wait ? sys->drain : sys->flush;
 105
 106     if (cb != NULL)
 107         cb (sys->opaque);
 108 }
 109
 110 static int VolumeSet (audio_output_t *aout, float vol)
 111 {
 112     aout_sys_t *sys = aout->sys;
 113
 114     sys->volume = vol;
 115     if (sys->ready)
 116         return 0; /* sys->opaque is not yet defined... */
 117     return sys->set_volume (sys->opaque, vol, sys->mute) ? -1 : 0;
 118 }
 119
 120 static int MuteSet (audio_output_t *aout, bool mute)
 121 {
 122     aout_sys_t *sys = aout->sys;
 123
 124     sys->mute = mute;
 125     if (!sys->ready)
 126         return 0; /* sys->opaque is not yet defined... */
 127     return sys->set_volume (sys->opaque, sys->volume, mute) ? -1 : 0;
 128 }
 129
 130 static int SoftVolumeSet (audio_output_t *aout, float vol)
 131 {
 132     aout_sys_t *sys = aout->sys;
 133
 134     vol = vol * vol * vol;
 135     if (!sys->mute && aout_GainRequest (aout, vol))
 136         return -1;
 137     sys->volume = vol;
 138     return 0;
 139 }
 140
 141 static int SoftMuteSet (audio_output_t *aout, bool mute)
 142 {
 143     aout_sys_t *sys = aout->sys;
 144
 145     if (aout_GainRequest (aout, mute ? 0.f : sys->volume))
 146         return -1;
 147     sys->mute = mute;
 148     return 0;
 149 }
 150
 151 static void Stop (audio_output_t *aout)
 152 {
 153     aout_sys_t *sys = aout->sys;
 154
 155     if (sys->cleanup != NULL)
 156         sys->cleanup (sys->opaque);
 157     sys->ready = false;
 158 }
 159
 160 static int Start (audio_output_t *aout, audio_sample_format_t *fmt)
 161 {
 162     aout_sys_t *sys = aout->sys;
 163     char format[5] = "S16N";
 164     unsigned channels;
 165
 166     if (aout_FormatNbChannels(fmt) == 0)
 167         return VLC_EGENERIC;
 168
 169     if (sys->setup != NULL)
 170     {
 171         channels = aout_FormatNbChannels(fmt);
 172
 173         sys->opaque = sys->setup_opaque;
 174         if (sys->setup (&sys->opaque, format, &fmt->i_rate, &channels))
 175             return VLC_EGENERIC;
 176     }
 177     else
 178     {
 179         fmt->i_rate = sys->rate;
 180         channels = sys->channels;
 181     }
 182
 183     /* Initialize volume (in case the UI changed volume before setup) */
 184     sys->ready = true;
 185     if (sys->set_volume != NULL)
 186         sys->set_volume(sys->opaque, sys->volume, sys->mute);
 187
 188     /* Ensure that format is supported */
 189     if (fmt->i_rate == 0 || fmt->i_rate > 192000
 190      || channels == 0 || channels > AOUT_CHAN_MAX
 191      || strcmp(format, "S16N") /* TODO: amem-format */)
 192     {
 193         msg_Err (aout, "format not supported: %s, %u channel(s), %u Hz",
 194                  format, channels, fmt->i_rate);
 195         Stop (aout);
 196         return VLC_EGENERIC;
 197     }
 198
 199     /* channel mapping */
 200     switch (channels)
 201     {
 202         case 1:
 203             fmt->i_physical_channels = AOUT_CHAN_CENTER;
 204             break;
 205         case 2:
 206             fmt->i_physical_channels = AOUT_CHANS_2_0;
 207             break;
 208         case 3:
 209             fmt->i_physical_channels = AOUT_CHANS_2_1;
 210             break;
 211         case 4:
 212             fmt->i_physical_channels = AOUT_CHANS_4_0;
 213             break;
 214         case 5:
 215             fmt->i_physical_channels = AOUT_CHANS_5_0;
 216             break;
 217         case 6:
 218             fmt->i_physical_channels = AOUT_CHANS_5_1;
 219             break;
 220         case 7:
 221             fmt->i_physical_channels =
 222                 AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
 223                 AOUT_CHAN_REARCENTER | AOUT_CHAN_MIDDLELEFT |
 224                 AOUT_CHAN_MIDDLERIGHT | AOUT_CHAN_LFE;
 225             break;
 226         case 8:
 227             fmt->i_physical_channels = AOUT_CHANS_7_1;
 228             break;
 229         default:
 230             vlc_assert_unreachable();
 231     }
 232
 233     fmt->i_format = VLC_CODEC_S16N;
 234     fmt->channel_type = AUDIO_CHANNEL_TYPE_BITMAP;
 235     return VLC_SUCCESS;
 236 }
 237
 238 static int Open (vlc_object_t *obj)
 239 {
 240     audio_output_t *aout = (audio_output_t *)obj;
 241     aout_sys_t *sys = malloc (sizeof (*sys));
 242     if (unlikely(sys == NULL))
 243         return VLC_ENOMEM;
 244
 245     void *opaque = var_InheritAddress (obj, "amem-data");
 246     sys->setup = var_InheritAddress (obj, "amem-setup");
 247     if (sys->setup != NULL)
 248     {
 249         sys->cleanup = var_InheritAddress (obj, "amem-cleanup");
 250         sys->setup_opaque = opaque;
 251     }
 252     else
 253     {
 254         sys->cleanup = NULL;
 255         sys->opaque = opaque;
 256         sys->rate = var_InheritInteger (obj, "amem-rate");
 257         sys->channels = var_InheritInteger (obj, "amem-channels");
 258     }
 259     sys->play = var_InheritAddress (obj, "amem-play");
 260     sys->pause = var_InheritAddress (obj, "amem-pause");
 261     sys->resume = var_InheritAddress (obj, "amem-resume");
 262     sys->flush = var_InheritAddress (obj, "amem-flush");
 263     sys->drain = var_InheritAddress (obj, "amem-drain");
 264     sys->set_volume = var_InheritAddress (obj, "amem-set-volume");
 265     sys->volume = 1.;
 266     sys->mute = false;
 267     sys->ready = false;
 268     if (sys->play == NULL)
 269     {
 270         free (sys);
 271         return VLC_EGENERIC;
 272     }
 273
 274     aout->sys = sys;
 275     aout->start = Start;
 276     aout->stop = Stop;
 277     aout->time_get = NULL;
 278     aout->play = Play;
 279     aout->pause = Pause;
 280     aout->flush = Flush;
 281     if (sys->set_volume != NULL)
 282     {
 283         aout->volume_set = VolumeSet;
 284         aout->mute_set = MuteSet;
 285     }
 286     else
 287     {
 288         aout->volume_set = SoftVolumeSet;
 289         aout->mute_set = SoftMuteSet;
 290     }
 291     return VLC_SUCCESS;
 292 }
 293
 294 static void Close (vlc_object_t *obj)
 295 {
 296     audio_output_t *aout = (audio_output_t *)obj;
 297     aout_sys_t *sys = aout->sys;
 298
 299     free (sys);
 300 }