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 /**
  27  * \defgroup audio_output Audio output
  28  * \ingroup output
  29  * @{
  30  * \file
  31  * Audio output modules interface
  32  */
  33
  34 /* Buffers which arrive in advance of more than AOUT_MAX_ADVANCE_TIME
  35  * will be considered as bogus and be trashed */
  36 #define AOUT_MAX_ADVANCE_TIME           (AOUT_MAX_PREPARE_TIME + CLOCK_FREQ)
  37
  38 /* Buffers which arrive in advance of more than AOUT_MAX_PREPARE_TIME
  39  * will cause the calling thread to sleep */
  40 #define AOUT_MAX_PREPARE_TIME           (2 * CLOCK_FREQ)
  41
  42 /* Buffers which arrive after pts - AOUT_MIN_PREPARE_TIME will be trashed
  43  * to avoid too heavy resampling */
  44 #define AOUT_MIN_PREPARE_TIME           AOUT_MAX_PTS_ADVANCE
  45
  46 /* Tolerance values from EBU Recommendation 37 */
  47 /** Maximum advance of actual audio playback time to coded PTS,
  48  * above which downsampling will be performed */
  49 #define AOUT_MAX_PTS_ADVANCE            (CLOCK_FREQ / 25)
  50
  51 /** Maximum delay of actual audio playback time from coded PTS,
  52  * above which upsampling will be performed */
  53 #define AOUT_MAX_PTS_DELAY              (3 * CLOCK_FREQ / 50)
  54
  55 /* Max acceptable resampling (in %) */
  56 #define AOUT_MAX_RESAMPLING             10
  57
  58 #include "vlc_es.h"
  59
  60 #define AOUT_FMTS_IDENTICAL( p_first, p_second ) (                          \
  61     ((p_first)->i_format == (p_second)->i_format)                           \
  62       && AOUT_FMTS_SIMILAR(p_first, p_second) )
  63
  64 /* Check if i_rate == i_rate and i_channels == i_channels */
  65 #define AOUT_FMTS_SIMILAR( p_first, p_second ) (                            \
  66     ((p_first)->i_rate == (p_second)->i_rate)                               \
  67       && ((p_first)->i_physical_channels == (p_second)->i_physical_channels)\
  68       && ((p_first)->i_original_channels == (p_second)->i_original_channels) )
  69
  70 #define AOUT_FMT_LINEAR( p_format ) \
  71     (aout_BitsPerSample((p_format)->i_format) != 0)
  72
  73 #define VLC_CODEC_SPDIFL VLC_FOURCC('s','p','d','i')
  74 #define VLC_CODEC_SPDIFB VLC_FOURCC('s','p','d','b')
  75
  76 #define AOUT_FMT_SPDIF( p_format ) \
  77     ( ((p_format)->i_format == VLC_CODEC_SPDIFL)       \
  78        || ((p_format)->i_format == VLC_CODEC_SPDIFB)   \
  79        || ((p_format)->i_format == VLC_CODEC_A52)      \
  80        || ((p_format)->i_format == VLC_CODEC_DTS) )
  81
  82 #define AOUT_FMT_HDMI( p_format )                   \
  83     ( (p_format)->i_format == VLC_CODEC_EAC3        \
  84     ||(p_format)->i_format == VLC_CODEC_TRUEHD      \
  85     ||(p_format)->i_format == VLC_CODEC_MLP         \
  86     )
  87
  88 /* Values used for the audio-channels object variable */
  89 #define AOUT_VAR_CHAN_UNSET         0 /* must be zero */
  90 #define AOUT_VAR_CHAN_STEREO        1
  91 #define AOUT_VAR_CHAN_RSTEREO       2
  92 #define AOUT_VAR_CHAN_LEFT          3
  93 #define AOUT_VAR_CHAN_RIGHT         4
  94 #define AOUT_VAR_CHAN_DOLBYS        5
  95
  96 /*****************************************************************************
  97  * Main audio output structures
  98  *****************************************************************************/
  99
 100 /* Size of a frame for S/PDIF output. */
 101 #define AOUT_SPDIF_SIZE 6144
 102
 103 /* Number of samples in an A/52 frame. */
 104 #define A52_FRAME_NB 1536
 105
 106 /* FIXME to remove once aout.h is cleaned a bit more */
 107 #include <vlc_block.h>
 108
 109 /** Audio output object */
 110 struct audio_output
 111 {
 112     VLC_COMMON_MEMBERS
 113
 114     struct aout_sys_t *sys; /**< Private data for callbacks */
 115
 116     int (*start)(audio_output_t *, audio_sample_format_t *fmt);
 117     /**< Starts a new stream (mandatory, cannot be NULL).
 118       * \param fmt input stream sample format upon entry,
 119       *            output stream sample format upon return [IN/OUT]
 120       * \return VLC_SUCCESS on success, non-zero on failure
 121       * \note No other stream may be already started when called.
 122       */
 123     void (*stop)(audio_output_t *);
 124     /**< Stops the existing stream (optional, may be NULL).
 125       * \note A stream must have been started when called.
 126       */
 127     int (*time_get)(audio_output_t *, mtime_t *delay);
 128     /**< Estimates playback buffer latency (optional, may be NULL).
 129       * \param delay pointer to the delay until the next sample to be written
 130       *              to the playback buffer is rendered [OUT]
 131       * \return 0 on success, non-zero on failure or lack of data
 132       * \note A stream must have been started when called.
 133       */
 134     void (*play)(audio_output_t *, block_t *);
 135     /**< Queues a block of samples for playback (mandatory, cannot be NULL).
 136       * \note A stream must have been started when called.
 137       */
 138     void (*pause)( audio_output_t *, bool pause, mtime_t date);
 139     /**< Pauses or resumes playback (optional, may be NULL).
 140       * \param pause pause if true, resume from pause if false
 141       * \param date timestamp when the pause or resume was requested
 142       * \note A stream must have been started when called.
 143       */
 144     void (*flush)( audio_output_t *, bool wait);
 145     /**< Flushes or drains the playback buffers (mandatory, cannot be NULL).
 146       * \param wait true to wait for playback of pending buffers (drain),
 147       *             false to discard pending buffers (flush)
 148       * \note A stream must have been started when called.
 149       */
 150     int (*volume_set)(audio_output_t *, float volume);
 151     /**< Changes playback volume (optional, may be NULL).
 152       * \param volume requested volume (0. = mute, 1. = nominal)
 153       * \note The volume is always a positive number.
 154       * \warning A stream may or may not have been started when called.
 155       */
 156     int (*mute_set)(audio_output_t *, bool mute);
 157     /**< Changes muting (optinal, may be NULL).
 158       * \param mute true to mute, false to unmute
 159       * \warning A stream may or may not have been started when called.
 160       */
 161     int (*device_select)(audio_output_t *, const char *id);
 162     /**< Selects an audio output device (optional, may be NULL).
 163       * \param id nul-terminated device unique identifier.
 164       * \return 0 on success, non-zero on failure.
 165       * \warning A stream may or may not have been started when called.
 166       */
 167     struct {
 168         void (*volume_report)(audio_output_t *, float);
 169         void (*mute_report)(audio_output_t *, bool);
 170         void (*policy_report)(audio_output_t *, bool);
 171         void (*device_report)(audio_output_t *, const char *);
 172         void (*hotplug_report)(audio_output_t *, const char *, const char *);
 173         int (*gain_request)(audio_output_t *, float);
 174         void (*restart_request)(audio_output_t *, unsigned);
 175     } event;
 176 };
 177
 178 /**
 179  * It describes the audio channel order VLC expect.
 180  */
 181 static const uint32_t pi_vlc_chan_order_wg4[] =
 182 {
 183     AOUT_CHAN_LEFT, AOUT_CHAN_RIGHT,
 184     AOUT_CHAN_MIDDLELEFT, AOUT_CHAN_MIDDLERIGHT,
 185     AOUT_CHAN_REARLEFT, AOUT_CHAN_REARRIGHT, AOUT_CHAN_REARCENTER,
 186     AOUT_CHAN_CENTER, AOUT_CHAN_LFE, 0
 187 };
 188
 189 #define AOUT_RESTART_FILTERS 1
 190 #define AOUT_RESTART_OUTPUT  2
 191
 192 /*****************************************************************************
 193  * Prototypes
 194  *****************************************************************************/
 195
 196 /**
 197  * This function computes the reordering needed to go from pi_chan_order_in to
 198  * pi_chan_order_out.
 199  * If pi_chan_order_in or pi_chan_order_out is NULL, it will assume that vlc
 200  * internal (WG4) order is requested.
 201  */
 202 VLC_API unsigned aout_CheckChannelReorder( const uint32_t *, const uint32_t *,
 203                                            uint32_t mask, uint8_t *table );
 204 VLC_API void aout_ChannelReorder(void *, size_t, uint8_t, const uint8_t *, vlc_fourcc_t);
 205
 206 VLC_API void aout_Interleave(void *dst, const void *const *planes,
 207                              unsigned samples, unsigned channels,
 208                              vlc_fourcc_t fourcc);
 209 VLC_API void aout_Deinterleave(void *dst, const void *src, unsigned samples,
 210                              unsigned channels, vlc_fourcc_t fourcc);
 211
 212 /**
 213  * This function will compute the extraction parameter into pi_selection to go
 214  * from i_channels with their type given by pi_order_src[] into the order
 215  * describe by pi_order_dst.
 216  * It will also set :
 217  * - *pi_channels as the number of channels that will be extracted which is
 218  * lower (in case of non understood channels type) or equal to i_channels.
 219  * - the layout of the channels (*pi_layout).
 220  *
 221  * It will return true if channel extraction is really needed, in which case
 222  * aout_ChannelExtract must be used
 223  *
 224  * XXX It must be used when the source may have channel type not understood
 225  * by VLC. In this case the channel type pi_order_src[] must be set to 0.
 226  * XXX It must also be used if multiple channels have the same type.
 227  */
 228 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 );
 229
 230 /**
 231  * Do the actual channels extraction using the parameters created by
 232  * aout_CheckChannelExtraction.
 233  *
 234  * XXX this function does not work in place (p_dst and p_src must not overlap).
 235  * XXX Only 8, 16, 24, 32, 64 bits per sample are supported.
 236  */
 237 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 );
 238
 239 /* */
 240 static inline unsigned aout_FormatNbChannels(const audio_sample_format_t *fmt)
 241 {
 242     return popcount(fmt->i_physical_channels);
 243 }
 244
 245 VLC_API unsigned int aout_BitsPerSample( vlc_fourcc_t i_format ) VLC_USED;
 246 VLC_API void aout_FormatPrepare( audio_sample_format_t * p_format );
 247 VLC_API void aout_FormatPrint(vlc_object_t *, const char *,
 248                               const audio_sample_format_t *);
 249 #define aout_FormatPrint(o, t, f) aout_FormatPrint(VLC_OBJECT(o), t, f)
 250 VLC_API const char * aout_FormatPrintChannels( const audio_sample_format_t * ) VLC_USED;
 251
 252 VLC_API float aout_VolumeGet (audio_output_t *);
 253 VLC_API int aout_VolumeSet (audio_output_t *, float);
 254 VLC_API int aout_MuteGet (audio_output_t *);
 255 VLC_API int aout_MuteSet (audio_output_t *, bool);
 256 VLC_API char *aout_DeviceGet (audio_output_t *);
 257 VLC_API int aout_DeviceSet (audio_output_t *, const char *);
 258 VLC_API int aout_DevicesList (audio_output_t *, char ***, char ***);
 259
 260 /**
 261  * Report change of configured audio volume to the core and UI.
 262  */
 263 static inline void aout_VolumeReport(audio_output_t *aout, float volume)
 264 {
 265     aout->event.volume_report(aout, volume);
 266 }
 267
 268 /**
 269  * Report change of muted flag to the core and UI.
 270  */
 271 static inline void aout_MuteReport(audio_output_t *aout, bool mute)
 272 {
 273     aout->event.mute_report(aout, mute);
 274 }
 275
 276 /**
 277  * Report audio policy status.
 278  * \param cork true to request a cork, false to undo any pending cork.
 279  */
 280 static inline void aout_PolicyReport(audio_output_t *aout, bool cork)
 281 {
 282     aout->event.policy_report(aout, cork);
 283 }
 284
 285 /**
 286  * Report change of output device.
 287  */
 288 static inline void aout_DeviceReport(audio_output_t *aout, const char *id)
 289 {
 290     aout->event.device_report(aout, id);
 291 }
 292
 293 /**
 294  * Report a device hot-plug event.
 295  * @param id device ID
 296  * @param name human-readable device name (NULL for hot unplug)
 297  */
 298 static inline void aout_HotplugReport(audio_output_t *aout,
 299                                       const char *id, const char *name)
 300 {
 301     aout->event.hotplug_report(aout, id, name);
 302 }
 303
 304 /**
 305  * Request a change of software audio amplification.
 306  * \param gain linear amplitude gain (must be positive)
 307  * \warning Values in excess 1.0 may cause overflow and distorsion.
 308  */
 309 static inline int aout_GainRequest(audio_output_t *aout, float gain)
 310 {
 311     return aout->event.gain_request(aout, gain);
 312 }
 313
 314 static inline void aout_RestartRequest(audio_output_t *aout, unsigned mode)
 315 {
 316     aout->event.restart_request(aout, mode);
 317 }
 318
 319 static inline int aout_ChannelsRestart (vlc_object_t *obj, const char *varname,
 320                             vlc_value_t oldval, vlc_value_t newval, void *data)
 321 {
 322     audio_output_t *aout = (audio_output_t *)obj;
 323     (void)varname; (void)oldval; (void)newval; (void)data;
 324
 325     aout_RestartRequest (aout, AOUT_RESTART_OUTPUT);
 326     return 0;
 327 }
 328
 329 /* Audio output filters */
 330 typedef struct aout_filters aout_filters_t;
 331 typedef struct aout_request_vout aout_request_vout_t;
 332
 333 VLC_API aout_filters_t *aout_FiltersNew(vlc_object_t *,
 334                                         const audio_sample_format_t *,
 335                                         const audio_sample_format_t *,
 336                                         const aout_request_vout_t *) VLC_USED;
 337 #define aout_FiltersNew(o,inf,outf,rv) \
 338         aout_FiltersNew(VLC_OBJECT(o),inf,outf,rv)
 339 VLC_API void aout_FiltersDelete(vlc_object_t *, aout_filters_t *);
 340 #define aout_FiltersDelete(o,f) \
 341         aout_FiltersDelete(VLC_OBJECT(o),f)
 342 VLC_API bool aout_FiltersAdjustResampling(aout_filters_t *, int);
 343 VLC_API block_t *aout_FiltersPlay(aout_filters_t *, block_t *, int rate);
 344 VLC_API block_t *aout_FiltersDrain(aout_filters_t *);
 345 VLC_API void     aout_FiltersFlush(aout_filters_t *);
 346
 347 VLC_API vout_thread_t * aout_filter_RequestVout( filter_t *, vout_thread_t *p_vout, video_format_t *p_fmt );
 348
 349 /** @} */
 350
 351 #endif /* VLC_AOUT_H */