include/vlc_aout.h

   1 /*****************************************************************************
   2  * vlc_aout.h : audio output interface
   3  *****************************************************************************
   4  * Copyright (C) 2002-2011 VLC authors and VideoLAN
   5  *
   6  * Authors: Christophe Massiot <massiot@via.ecp.fr>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either version 2.1 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22
  23 #ifndef VLC_AOUT_H
  24 #define VLC_AOUT_H 1
  25
  26 #include <assert.h>
  27
  28 /**
  29  * \defgroup audio_output Audio output
  30  * \ingroup output
  31  * @{
  32  * \file
  33  * Audio output modules interface
  34  */
  35
  36 /* Buffers which arrive in advance of more than AOUT_MAX_ADVANCE_TIME
  37  * will be considered as bogus and be trashed */
  38 #define AOUT_MAX_ADVANCE_TIME           (AOUT_MAX_PREPARE_TIME + VLC_TICK_FROM_SEC(1))
  39
  40 /* Buffers which arrive in advance of more than AOUT_MAX_PREPARE_TIME
  41  * will cause the calling thread to sleep */
  42 #define AOUT_MAX_PREPARE_TIME           VLC_TICK_FROM_SEC(2)
  43
  44 /* Buffers which arrive after pts - AOUT_MIN_PREPARE_TIME will be trashed
  45  * to avoid too heavy resampling */
  46 #define AOUT_MIN_PREPARE_TIME           AOUT_MAX_PTS_ADVANCE
  47
  48 /* Tolerance values from EBU Recommendation 37 */
  49 /** Maximum advance of actual audio playback time to coded PTS,
  50  * above which downsampling will be performed */
  51 #define AOUT_MAX_PTS_ADVANCE            VLC_TICK_FROM_MS(40)
  52
  53 /** Maximum delay of actual audio playback time from coded PTS,
  54  * above which upsampling will be performed */
  55 #define AOUT_MAX_PTS_DELAY              VLC_TICK_FROM_MS(60)
  56
  57 /* Max acceptable resampling (in %) */
  58 #define AOUT_MAX_RESAMPLING             10
  59
  60 #include "vlc_es.h"
  61
  62 #define AOUT_FMTS_IDENTICAL( p_first, p_second ) (                          \
  63     ((p_first)->i_format == (p_second)->i_format)                           \
  64       && AOUT_FMTS_SIMILAR(p_first, p_second) )
  65
  66 /* Check if i_rate == i_rate and i_channels == i_channels */
  67 #define AOUT_FMTS_SIMILAR( p_first, p_second ) (                            \
  68     ((p_first)->i_rate == (p_second)->i_rate)                               \
  69       && ((p_first)->channel_type == (p_second)->channel_type)            \
  70       && ((p_first)->i_physical_channels == (p_second)->i_physical_channels)\
  71       && ((p_first)->i_chan_mode == (p_second)->i_chan_mode) )
  72
  73 #define AOUT_FMT_LINEAR( p_format ) \
  74     (aout_BitsPerSample((p_format)->i_format) != 0)
  75
  76 #define VLC_CODEC_SPDIFL VLC_FOURCC('s','p','d','i')
  77 #define VLC_CODEC_SPDIFB VLC_FOURCC('s','p','d','b')
  78
  79 #define AOUT_FMT_SPDIF( p_format ) \
  80     ( ((p_format)->i_format == VLC_CODEC_SPDIFL)       \
  81        || ((p_format)->i_format == VLC_CODEC_SPDIFB)   \
  82        || ((p_format)->i_format == VLC_CODEC_A52)      \
  83        || ((p_format)->i_format == VLC_CODEC_DTS) )
  84
  85 #define AOUT_FMT_HDMI( p_format )                   \
  86     ( (p_format)->i_format == VLC_CODEC_EAC3        \
  87     ||(p_format)->i_format == VLC_CODEC_DTSHD       \
  88     ||(p_format)->i_format == VLC_CODEC_TRUEHD      \
  89     ||(p_format)->i_format == VLC_CODEC_MLP         \
  90     )
  91
  92 /* Values used for the audio-channels object variable */
  93 #define AOUT_VAR_CHAN_UNSET         0 /* must be zero */
  94 #define AOUT_VAR_CHAN_STEREO        1
  95 #define AOUT_VAR_CHAN_RSTEREO       2
  96 #define AOUT_VAR_CHAN_LEFT          3
  97 #define AOUT_VAR_CHAN_RIGHT         4
  98 #define AOUT_VAR_CHAN_DOLBYS        5
  99 #define AOUT_VAR_CHAN_HEADPHONES    6
 100 #define AOUT_VAR_CHAN_MONO          7
 101
 102 /*****************************************************************************
 103  * Main audio output structures
 104  *****************************************************************************/
 105
 106 /* Size of a frame for S/PDIF output. */
 107 #define AOUT_SPDIF_SIZE 6144
 108
 109 /* Number of samples in an A/52 frame. */
 110 #define A52_FRAME_NB 1536
 111
 112 /* FIXME to remove once aout.h is cleaned a bit more */
 113 #include <vlc_block.h>
 114
 115 struct vlc_audio_output_events {
 116     void (*timing_report)(audio_output_t *, vlc_tick_t system_now, vlc_tick_t pts);
 117     void (*volume_report)(audio_output_t *, float);
 118     void (*mute_report)(audio_output_t *, bool);
 119     void (*policy_report)(audio_output_t *, bool);
 120     void (*device_report)(audio_output_t *, const char *);
 121     void (*hotplug_report)(audio_output_t *, const char *, const char *);
 122     void (*restart_request)(audio_output_t *, unsigned);
 123     int (*gain_request)(audio_output_t *, float);
 124 };
 125
 126 /** Audio output object
 127  *
 128  * The audio output object is the abstraction for rendering decoded
 129  * (or pass-through) audio samples. In addition to playing samples,
 130  * the abstraction exposes controls for pause/resume, flush/drain,
 131  * changing the volume or mut flag, and listing and changing output device.
 132  *
 133  * An audio output can be in one of three different states:
 134  * stopped, playing or paused.
 135  * The audio output is always created in stopped state and is always destroyed
 136  * in that state also. It is moved from stopped to playing state by start(),
 137  * and from playing or paused states back to stopped state by stop().
 138  **/
 139 struct audio_output
 140 {
 141     struct vlc_object_t obj;
 142
 143     void *sys; /**< Private data for callbacks */
 144
 145     int (*start)(audio_output_t *, audio_sample_format_t *fmt);
 146     /**< Starts a new stream (mandatory, cannot be NULL).
 147       *
 148       * This callback changes the audio output from stopped to playing state
 149       * (if succesful). After the callback returns, time_get(), play(),
 150       * pause(), flush() and eventually stop() callbacks may be called.
 151       *
 152       * \param fmt input stream sample format upon entry,
 153       *            output stream sample format upon return [IN/OUT]
 154       * \return VLC_SUCCESS on success, non-zero on failure
 155       *
 156       * \note This callback can only be called while the audio output is in
 157       * stopped state. There can be only one stream per audio output at a time.
 158       *
 159       * \note This callbacks needs not be reentrant.
 160       */
 161
 162     void (*stop)(audio_output_t *);
 163     /**< Stops the existing stream (mandatory, cannot be NULL).
 164       *
 165       * This callback terminates the current audio stream,
 166       * and returns the audio output to stopped state.
 167       *
 168       * \note This callback needs not be reentrant.
 169       */
 170
 171     int (*time_get)(audio_output_t *, vlc_tick_t *delay);
 172     /**< Estimates playback buffer latency (mandatory, cannot be NULL).
 173       *
 174       * This callback computes an estimation of the delay until the current
 175       * tail of the audio output buffer would be rendered. This is essential
 176       * for (lip) synchronization and long term drift between the audio output
 177       * clock and the media upstream clock (if any).
 178       *
 179       * If the audio output clock is exactly synchronized with the system
 180       * monotonic clock (i.e. vlc_tick_now()), then aout_TimeGetDefault() can
 181       * implement this callback. In that case, drain must be implemented (since
 182       * the default implementation uses the delay to wait for the end of the
 183       * stream).
 184       *
 185       * This callback is called before the first play() in order to get the
 186       * initial delay (the hw latency). Most modules won't be able to know this
 187       * latency before the first play. In that case, they should return -1 and
 188       * handle the first play() date, cf. play() documentation.
 189       *
 190       * \param delay pointer to the delay until the next sample to be written
 191       *              to the playback buffer is rendered [OUT]
 192       * \return 0 on success, non-zero on failure or lack of data
 193       *
 194       * \note This callback cannot be called in stopped state.
 195       */
 196
 197     void (*play)(audio_output_t *, block_t *block, vlc_tick_t date);
 198     /**< Queues a block of samples for playback (mandatory, cannot be NULL).
 199       *
 200       * The first play() date (after a flush()/start()) will be most likely in
 201       * the future. Modules that don't know the hw latency before a first play
 202       * (when they return -1 from the first time_get()) will need to handle
 203       * this. They can play a silence buffer with 'length = date - now()', or
 204       * configure their render callback to start at the given date.
 205       *
 206       * \param block block of audio samples
 207       * \param date intended system time to render the first sample
 208       *
 209       * \note This callback cannot be called in stopped state.
 210       */
 211
 212     void (*pause)( audio_output_t *, bool pause, vlc_tick_t date);
 213     /**< Pauses or resumes playback (mandatory, cannot be NULL).
 214       *
 215       * This callback pauses or resumes audio playback as quickly as possible.
 216       * When pausing, it is desirable to stop producing sound immediately, but
 217       * retain already queued audio samples in the buffer to play when later
 218       * when resuming.
 219       *
 220       * If pausing is impossible, then aout_PauseDefault() can provide a
 221       * fallback implementation of this callback.
 222       *
 223       * \param pause pause if true, resume from pause if false
 224       * \param date timestamp when the pause or resume was requested
 225       *
 226       * \note This callback cannot be called in stopped state.
 227       */
 228
 229     void (*flush)( audio_output_t *);
 230     /**< Flushes the playback buffers (mandatory, cannot be NULL).
 231       *
 232       * \param wait true to wait for playback of pending buffers (drain),
 233       *             false to discard pending buffers (flush)
 234       *
 235       * \note This callback cannot be called in stopped state.
 236       */
 237     void (*drain)(audio_output_t *);
 238     /**< Drain the playback buffers (can be NULL).
 239       *
 240       * If NULL, the caller will wait for the delay returned by time_get before
 241       * calling stop().
 242       */
 243
 244     int (*volume_set)(audio_output_t *, float volume);
 245     /**< Changes playback volume (optional, may be NULL).
 246       *
 247       * \param volume requested volume (0. = mute, 1. = nominal)
 248       *
 249       * \note The volume is always a positive number.
 250       *
 251       * \warning A stream may or may not have been started when called.
 252       * \warning This callback may be called concurrently with
 253       * time_get(), play(), pause() or flush().
 254       * It will however be protected against concurrent calls to
 255       * start(), stop(), volume_set(), mute_set() or device_select().
 256       */
 257
 258     int (*mute_set)(audio_output_t *, bool mute);
 259     /**< Changes muting (optinal, may be NULL).
 260       *
 261       * \param mute true to mute, false to unmute
 262       * \warning The same constraints apply as with volume_set().
 263       */
 264
 265     int (*device_select)(audio_output_t *, const char *id);
 266     /**< Selects an audio output device (optional, may be NULL).
 267       *
 268       * \param id nul-terminated device unique identifier.
 269       * \return 0 on success, non-zero on failure.
 270       *
 271       * \warning The same constraints apply as with volume_set().
 272       */
 273
 274     struct {
 275         bool headphones; /**< Default to false, set it to true if the current
 276                               sink is using headphones */
 277     } current_sink_info;
 278     /**< Current sink informations set by the module from the start() function */
 279
 280     const struct vlc_audio_output_events *events;
 281 };
 282
 283 typedef enum
 284 {
 285     AOUT_CHANIDX_DISABLE = -1,
 286     AOUT_CHANIDX_LEFT,
 287     AOUT_CHANIDX_RIGHT,
 288     AOUT_CHANIDX_MIDDLELEFT,
 289     AOUT_CHANIDX_MIDDLERIGHT,
 290     AOUT_CHANIDX_REARLEFT,
 291     AOUT_CHANIDX_REARRIGHT,
 292     AOUT_CHANIDX_REARCENTER,
 293     AOUT_CHANIDX_CENTER,
 294     AOUT_CHANIDX_LFE,
 295     AOUT_CHANIDX_MAX
 296 } vlc_chan_order_idx_t;
 297
 298 static_assert(AOUT_CHANIDX_MAX == AOUT_CHAN_MAX, "channel count mismatch");
 299
 300 #define AOUT_CHAN_REMAP_INIT { \
 301     AOUT_CHANIDX_LEFT,  \
 302     AOUT_CHANIDX_RIGHT, \
 303     AOUT_CHANIDX_MIDDLELEFT, \
 304     AOUT_CHANIDX_MIDDLERIGHT, \
 305     AOUT_CHANIDX_REARLEFT, \
 306     AOUT_CHANIDX_REARRIGHT, \
 307     AOUT_CHANIDX_REARCENTER, \
 308     AOUT_CHANIDX_CENTER, \
 309     AOUT_CHANIDX_LFE, \
 310 }
 311
 312 /**
 313  * It describes the audio channel order VLC expect.
 314  */
 315 static const uint32_t pi_vlc_chan_order_wg4[] =
 316 {
 317     AOUT_CHAN_LEFT, AOUT_CHAN_RIGHT,
 318     AOUT_CHAN_MIDDLELEFT, AOUT_CHAN_MIDDLERIGHT,
 319     AOUT_CHAN_REARLEFT, AOUT_CHAN_REARRIGHT, AOUT_CHAN_REARCENTER,
 320     AOUT_CHAN_CENTER, AOUT_CHAN_LFE, 0
 321 };
 322
 323 #define AOUT_RESTART_FILTERS        0x1
 324 #define AOUT_RESTART_OUTPUT         (AOUT_RESTART_FILTERS|0x2)
 325 #define AOUT_RESTART_STEREOMODE     (AOUT_RESTART_OUTPUT|0x4)
 326
 327 /*****************************************************************************
 328  * Prototypes
 329  *****************************************************************************/
 330
 331 /**
 332  * This function computes the reordering needed to go from pi_chan_order_in to
 333  * pi_chan_order_out.
 334  * If pi_chan_order_in or pi_chan_order_out is NULL, it will assume that vlc
 335  * internal (WG4) order is requested.
 336  */
 337 VLC_API unsigned aout_CheckChannelReorder( const uint32_t *, const uint32_t *,
 338                                            uint32_t mask, uint8_t *table );
 339 VLC_API void aout_ChannelReorder(void *, size_t, uint8_t, const uint8_t *, vlc_fourcc_t);
 340
 341 VLC_API void aout_Interleave(void *dst, const void *const *planes,
 342                              unsigned samples, unsigned channels,
 343                              vlc_fourcc_t fourcc);
 344 VLC_API void aout_Deinterleave(void *dst, const void *src, unsigned samples,
 345                              unsigned channels, vlc_fourcc_t fourcc);
 346
 347 /**
 348  * This function will compute the extraction parameter into pi_selection to go
 349  * from i_channels with their type given by pi_order_src[] into the order
 350  * describe by pi_order_dst.
 351  * It will also set :
 352  * - *pi_channels as the number of channels that will be extracted which is
 353  * lower (in case of non understood channels type) or equal to i_channels.
 354  * - the layout of the channels (*pi_layout).
 355  *
 356  * It will return true if channel extraction is really needed, in which case
 357  * aout_ChannelExtract must be used
 358  *
 359  * XXX It must be used when the source may have channel type not understood
 360  * by VLC. In this case the channel type pi_order_src[] must be set to 0.
 361  * XXX It must also be used if multiple channels have the same type.
 362  */
 363 VLC_API bool aout_CheckChannelExtraction( int *pi_selection, uint32_t *pi_layout, int *pi_channels, const uint32_t pi_order_dst[AOUT_CHAN_MAX], const uint32_t *pi_order_src, int i_channels );
 364
 365 /**
 366  * Do the actual channels extraction using the parameters created by
 367  * aout_CheckChannelExtraction.
 368  *
 369  * XXX this function does not work in place (p_dst and p_src must not overlap).
 370  * XXX Only 8, 16, 32, 64 bits per sample are supported.
 371  */
 372 VLC_API void aout_ChannelExtract( void *p_dst, int i_dst_channels, const void *p_src, int i_src_channels, int i_sample_count, const int *pi_selection, int i_bits_per_sample );
 373
 374 /* */
 375 static inline unsigned aout_FormatNbChannels(const audio_sample_format_t *fmt)
 376 {
 377     return vlc_popcount(fmt->i_physical_channels);
 378 }
 379
 380 VLC_API unsigned int aout_BitsPerSample( vlc_fourcc_t i_format ) VLC_USED;
 381 VLC_API void aout_FormatPrepare( audio_sample_format_t * p_format );
 382 VLC_API void aout_FormatPrint(vlc_object_t *, const char *,
 383                               const audio_sample_format_t *);
 384 #define aout_FormatPrint(o, t, f) aout_FormatPrint(VLC_OBJECT(o), t, f)
 385 VLC_API const char * aout_FormatPrintChannels( const audio_sample_format_t * ) VLC_USED;
 386
 387 #define AOUT_VOLUME_DEFAULT             256
 388 #define AOUT_VOLUME_MAX                 512
 389
 390 VLC_API float aout_VolumeGet (audio_output_t *);
 391 VLC_API int aout_VolumeSet (audio_output_t *, float);
 392 VLC_API int aout_VolumeUpdate (audio_output_t *, int, float *);
 393 VLC_API int aout_MuteGet (audio_output_t *);
 394 VLC_API int aout_MuteSet (audio_output_t *, bool);
 395 VLC_API char *aout_DeviceGet (audio_output_t *);
 396 VLC_API int aout_DeviceSet (audio_output_t *, const char *);
 397 VLC_API int aout_DevicesList (audio_output_t *, char ***, char ***);
 398
 399 /**
 400  * Report change of configured audio volume to the core and UI.
 401  */
 402 static inline void aout_VolumeReport(audio_output_t *aout, float volume)
 403 {
 404     aout->events->volume_report(aout, volume);
 405 }
 406
 407 /**
 408  * Report change of muted flag to the core and UI.
 409  */
 410 static inline void aout_MuteReport(audio_output_t *aout, bool mute)
 411 {
 412     aout->events->mute_report(aout, mute);
 413 }
 414
 415 /**
 416  * Report audio policy status.
 417  * \param cork true to request a cork, false to undo any pending cork.
 418  */
 419 static inline void aout_PolicyReport(audio_output_t *aout, bool cork)
 420 {
 421     aout->events->policy_report(aout, cork);
 422 }
 423
 424 /**
 425  * Report change of output device.
 426  */
 427 static inline void aout_DeviceReport(audio_output_t *aout, const char *id)
 428 {
 429     aout->events->device_report(aout, id);
 430 }
 431
 432 /**
 433  * Report a device hot-plug event.
 434  * @param id device ID
 435  * @param name human-readable device name (NULL for hot unplug)
 436  */
 437 static inline void aout_HotplugReport(audio_output_t *aout,
 438                                       const char *id, const char *name)
 439 {
 440     aout->events->hotplug_report(aout, id, name);
 441 }
 442
 443 /**
 444  * Request a change of software audio amplification.
 445  * \param gain linear amplitude gain (must be positive)
 446  * \warning Values in excess 1.0 may cause overflow and distorsion.
 447  */
 448 static inline int aout_GainRequest(audio_output_t *aout, float gain)
 449 {
 450     return aout->events->gain_request(aout, gain);
 451 }
 452
 453 static inline void aout_RestartRequest(audio_output_t *aout, unsigned mode)
 454 {
 455     aout->events->restart_request(aout, mode);
 456 }
 457
 458 /**
 459  * Default implementation for audio_output_t.time_get
 460  */
 461 static inline int aout_TimeGetDefault(audio_output_t *aout,
 462                                       vlc_tick_t *restrict delay)
 463 {
 464     (void) aout; (void) delay;
 465     return -1;
 466 }
 467
 468 /**
 469  * Default implementation for audio_output_t.pause
 470  *
 471  * \warning This default callback implementation is suboptimal as it will
 472  * discard some audio samples.
 473  * Do not use this unless there are really no possible better alternatives.
 474  */
 475 static inline void aout_PauseDefault(audio_output_t *aout, bool paused,
 476                                      vlc_tick_t date)
 477 {
 478     if (paused)
 479         aout->flush(aout);
 480     (void) date;
 481 }
 482
 483 /* Audio output filters */
 484
 485 /**
 486  * Enable or disable an audio filter ("audio-filter")
 487  *
 488  * \param aout a valid audio output
 489  * \param name a valid filter name
 490  * \param add true to add the filter, false to remove it
 491  * \return 0 on success, non-zero on failure.
 492  */
 493 VLC_API int aout_EnableFilter(audio_output_t *aout, const char *name, bool add);
 494
 495 typedef struct
 496 {
 497     /**
 498      * If the remap order differs from the WG4 order, a remap audio filter will
 499      * be inserted to remap channels according to this array.
 500      */
 501     int remap[AOUT_CHANIDX_MAX];
 502     /**
 503      * If true, a filter will be inserted to add a headphones effect (like a
 504      * binauralizer audio filter).
 505      */
 506     bool headphones;
 507 } aout_filters_cfg_t;
 508
 509 #define AOUT_FILTERS_CFG_INIT (aout_filters_cfg_t) \
 510     { .remap = AOUT_CHAN_REMAP_INIT, \
 511       .headphones = false, \
 512     };
 513
 514 typedef struct aout_filters aout_filters_t;
 515
 516 VLC_API aout_filters_t *aout_FiltersNew(vlc_object_t *,
 517                                         const audio_sample_format_t *,
 518                                         const audio_sample_format_t *,
 519                                         const aout_filters_cfg_t *cfg) VLC_USED;
 520 #define aout_FiltersNew(o,inf,outf,remap) \
 521         aout_FiltersNew(VLC_OBJECT(o),inf,outf,remap)
 522 VLC_API void aout_FiltersDelete(vlc_object_t *, aout_filters_t *);
 523 #define aout_FiltersDelete(o,f) \
 524         aout_FiltersDelete(VLC_OBJECT(o),f)
 525 VLC_API bool aout_FiltersAdjustResampling(aout_filters_t *, int);
 526 VLC_API block_t *aout_FiltersPlay(aout_filters_t *, block_t *, float rate);
 527 VLC_API block_t *aout_FiltersDrain(aout_filters_t *);
 528 VLC_API void     aout_FiltersFlush(aout_filters_t *);
 529 VLC_API void     aout_FiltersChangeViewpoint(aout_filters_t *, const vlc_viewpoint_t *vp);
 530
 531 VLC_API vout_thread_t *aout_filter_GetVout(filter_t *, const video_format_t *);
 532
 533 /** @} */
 534
 535 #endif /* VLC_AOUT_H */