git.sesse.net Git - vlc/blob - modules/audio_output/directx.c

   1 /*****************************************************************************
   2  * directx.c: Windows DirectX audio output method
   3  *****************************************************************************
   4  * Copyright (C) 2001 VideoLAN
   5  * $Id: directx.c,v 1.24 2003/12/15 21:35:37 gbazin Exp $
   6  *
   7  * Authors: Gildas Bazin <gbazin@netcourrier.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include <errno.h>                                                 /* ENOMEM */
  28 #include <fcntl.h>                                       /* open(), O_WRONLY */
  29 #include <string.h>                                            /* strerror() */
  30
  31 #include <stdlib.h>                            /* calloc(), malloc(), free() */
  32
  33 #include <vlc/vlc.h>
  34 #include <vlc/aout.h>
  35 #include "aout_internal.h"
  36
  37 #include <windows.h>
  38 #include <mmsystem.h>
  39 #include <dsound.h>
  40
  41 #define FRAME_SIZE 2048              /* The size is in samples, not in bytes */
  42 #define FRAMES_NUM 8
  43
  44 /* frame buffer status */
  45 #define FRAME_QUEUED 0
  46 #define FRAME_EMPTY 1
  47
  48 /*****************************************************************************
  49  * DirectSound GUIDs.
  50  * Defining them here allows us to get rid of the dxguid library during
  51  * the linking stage.
  52  *****************************************************************************/
  53 #include <initguid.h>
  54 DEFINE_GUID(IID_IDirectSoundNotify, 0xb0210783, 0x89cd, 0x11d0, 0xaf, 0x8, 0x0, 0xa0, 0xc9, 0x25, 0xcd, 0x16);
  55
  56 /*****************************************************************************
  57  * Useful macros
  58  *****************************************************************************/
  59 #ifndef WAVE_FORMAT_IEEE_FLOAT
  60 #   define WAVE_FORMAT_IEEE_FLOAT 0x0003
  61 #endif
  62
  63 #ifndef WAVE_FORMAT_DOLBY_AC3_SPDIF
  64 #   define WAVE_FORMAT_DOLBY_AC3_SPDIF 0x0092
  65 #endif
  66
  67 #ifndef WAVE_FORMAT_EXTENSIBLE
  68 #define  WAVE_FORMAT_EXTENSIBLE   0xFFFE
  69 #endif
  70
  71 #ifndef SPEAKER_FRONT_LEFT
  72 #   define SPEAKER_FRONT_LEFT             0x1
  73 #   define SPEAKER_FRONT_RIGHT            0x2
  74 #   define SPEAKER_FRONT_CENTER           0x4
  75 #   define SPEAKER_LOW_FREQUENCY          0x8
  76 #   define SPEAKER_BACK_LEFT              0x10
  77 #   define SPEAKER_BACK_RIGHT             0x20
  78 #   define SPEAKER_FRONT_LEFT_OF_CENTER   0x40
  79 #   define SPEAKER_FRONT_RIGHT_OF_CENTER  0x80
  80 #   define SPEAKER_BACK_CENTER            0x100
  81 #   define SPEAKER_SIDE_LEFT              0x200
  82 #   define SPEAKER_SIDE_RIGHT             0x400
  83 #   define SPEAKER_TOP_CENTER             0x800
  84 #   define SPEAKER_TOP_FRONT_LEFT         0x1000
  85 #   define SPEAKER_TOP_FRONT_CENTER       0x2000
  86 #   define SPEAKER_TOP_FRONT_RIGHT        0x4000
  87 #   define SPEAKER_TOP_BACK_LEFT          0x8000
  88 #   define SPEAKER_TOP_BACK_CENTER        0x10000
  89 #   define SPEAKER_TOP_BACK_RIGHT         0x20000
  90 #   define SPEAKER_RESERVED               0x80000000
  91 #endif
  92
  93 #ifndef DSSPEAKER_HEADPHONE
  94 #   define DSSPEAKER_HEADPHONE         0x00000001
  95 #endif
  96 #ifndef DSSPEAKER_MONO
  97 #   define DSSPEAKER_MONO              0x00000002
  98 #endif
  99 #ifndef DSSPEAKER_QUAD
 100 #   define DSSPEAKER_QUAD              0x00000003
 101 #endif
 102 #ifndef DSSPEAKER_STEREO
 103 #   define DSSPEAKER_STEREO            0x00000004
 104 #endif
 105 #ifndef DSSPEAKER_SURROUND
 106 #   define DSSPEAKER_SURROUND          0x00000005
 107 #endif
 108 #ifndef DSSPEAKER_5POINT1
 109 #   define DSSPEAKER_5POINT1           0x00000006
 110 #endif
 111
 112 #ifndef _WAVEFORMATEXTENSIBLE_
 113 typedef struct {
 114     WAVEFORMATEX    Format;
 115     union {
 116         WORD wValidBitsPerSample;       /* bits of precision  */
 117         WORD wSamplesPerBlock;          /* valid if wBitsPerSample==0 */
 118         WORD wReserved;                 /* If neither applies, set to zero. */
 119     } Samples;
 120     DWORD           dwChannelMask;      /* which channels are */
 121                                         /* present in stream  */
 122     GUID            SubFormat;
 123 } WAVEFORMATEXTENSIBLE, *PWAVEFORMATEXTENSIBLE;
 124 #endif
 125
 126 DEFINE_GUID( _KSDATAFORMAT_SUBTYPE_IEEE_FLOAT, WAVE_FORMAT_IEEE_FLOAT, 0x0000, 0x0010, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71 );
 127 DEFINE_GUID( _KSDATAFORMAT_SUBTYPE_PCM, WAVE_FORMAT_PCM, 0x0000, 0x0010, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71 );
 128 DEFINE_GUID( _KSDATAFORMAT_SUBTYPE_DOLBY_AC3_SPDIF, WAVE_FORMAT_DOLBY_AC3_SPDIF, 0x0000, 0x0010, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71 );
 129
 130 /*****************************************************************************
 131  * notification_thread_t: DirectX event thread
 132  *****************************************************************************/
 133 typedef struct notification_thread_t
 134 {
 135     VLC_COMMON_MEMBERS
 136
 137     aout_instance_t * p_aout;
 138     int i_frame_status[FRAMES_NUM];           /* status of each frame buffer */
 139     DSBPOSITIONNOTIFY p_events[FRAMES_NUM];      /* play notification events */
 140     int i_frame_size;                         /* Size in bytes of one frame */
 141
 142     mtime_t start_date;
 143
 144 } notification_thread_t;
 145
 146 /*****************************************************************************
 147  * aout_sys_t: directx audio output method descriptor
 148  *****************************************************************************
 149  * This structure is part of the audio output thread descriptor.
 150  * It describes the direct sound specific properties of an audio device.
 151  *****************************************************************************/
 152 struct aout_sys_t
 153 {
 154     HINSTANCE           hdsound_dll;      /* handle of the opened dsound dll */
 155     LPDIRECTSOUND       p_dsobject;              /* main Direct Sound object */
 156     LPDIRECTSOUNDBUFFER p_dsbuffer;   /* the sound buffer we use (direct sound
 157                                        * takes care of mixing all the
 158                                        * secondary buffers into the primary) */
 159
 160     LPDIRECTSOUNDNOTIFY p_dsnotify;         /* the position notify interface */
 161     notification_thread_t *p_notif;                  /* DirectSoundThread id */
 162
 163     int b_playing;                                         /* playing status */
 164
 165     int i_frame_size;                         /* Size in bytes of one frame */
 166
 167     vlc_bool_t b_chan_reorder;              /* do we need channel reordering */
 168     int *pi_chan_table;
 169     uint32_t i_channel_mask;
 170 };
 171
 172 static const uint32_t pi_channels_in[] =
 173     { AOUT_CHAN_LEFT, AOUT_CHAN_RIGHT,
 174       AOUT_CHAN_REARLEFT, AOUT_CHAN_REARRIGHT,
 175       AOUT_CHAN_CENTER, AOUT_CHAN_LFE };
 176 static const uint32_t pi_channels_out[] =
 177     { SPEAKER_FRONT_LEFT, SPEAKER_FRONT_RIGHT,
 178       SPEAKER_BACK_LEFT, SPEAKER_BACK_RIGHT,
 179       SPEAKER_FRONT_CENTER, SPEAKER_LOW_FREQUENCY };
 180 static const uint32_t pi_channels_ordered[] =
 181     { SPEAKER_FRONT_LEFT, SPEAKER_FRONT_RIGHT, SPEAKER_FRONT_CENTER,
 182       SPEAKER_LOW_FREQUENCY,
 183       SPEAKER_BACK_LEFT, SPEAKER_BACK_RIGHT };
 184
 185 /*****************************************************************************
 186  * Local prototypes.
 187  *****************************************************************************/
 188 static int  OpenAudio  ( vlc_object_t * );
 189 static void CloseAudio ( vlc_object_t * );
 190 static void Play       ( aout_instance_t * );
 191
 192 /* local functions */
 193 static void Probe             ( aout_instance_t * );
 194 static int  InitDirectSound   ( aout_instance_t * );
 195 static int  CreateDSBuffer    ( aout_instance_t *, int, int, int, int, int, vlc_bool_t );
 196 static int  CreateDSBufferPCM ( aout_instance_t *, int*, int, int, int, vlc_bool_t );
 197 static void DestroyDSBuffer   ( aout_instance_t * );
 198 static void DirectSoundThread ( notification_thread_t * );
 199 static int  FillBuffer        ( aout_instance_t *, int, aout_buffer_t * );
 200
 201 static void CheckReordering   ( aout_instance_t *, int );
 202 static void InterleaveFloat32 ( float *, float *, int *, int );
 203 static void InterleaveS16     ( int16_t *, int16_t *, int *, int );
 204
 205 /*****************************************************************************
 206  * Module descriptor
 207  *****************************************************************************/
 208 vlc_module_begin();
 209     set_description( _("DirectX audio output") );
 210     set_capability( "audio output", 100 );
 211     add_shortcut( "directx" );
 212     set_callbacks( OpenAudio, CloseAudio );
 213 vlc_module_end();
 214
 215 /*****************************************************************************
 216  * OpenAudio: open the audio device
 217  *****************************************************************************
 218  * This function opens and setups Direct Sound.
 219  *****************************************************************************/
 220 static int OpenAudio( vlc_object_t *p_this )
 221 {
 222     aout_instance_t * p_aout = (aout_instance_t *)p_this;
 223     vlc_value_t val;
 224     int i;
 225
 226     msg_Dbg( p_aout, "OpenAudio" );
 227
 228    /* Allocate structure */
 229     p_aout->output.p_sys = malloc( sizeof( aout_sys_t ) );
 230     if( p_aout->output.p_sys == NULL )
 231     {
 232         msg_Err( p_aout, "out of memory" );
 233         return VLC_EGENERIC;
 234     }
 235
 236     /* Initialize some variables */
 237     p_aout->output.p_sys->p_dsobject = NULL;
 238     p_aout->output.p_sys->p_dsbuffer = NULL;
 239     p_aout->output.p_sys->p_dsnotify = NULL;
 240     p_aout->output.p_sys->p_notif = NULL;
 241     p_aout->output.p_sys->b_playing = 0;
 242     p_aout->output.p_sys->pi_chan_table = NULL;
 243
 244     p_aout->output.pf_play = Play;
 245     aout_VolumeSoftInit( p_aout );
 246
 247     /* Initialise DirectSound */
 248     if( InitDirectSound( p_aout ) )
 249     {
 250         msg_Err( p_aout, "cannot initialize DirectSound" );
 251         goto error;
 252     }
 253
 254     if( var_Type( p_aout, "audio-device" ) == 0 )
 255     {
 256         Probe( p_aout );
 257     }
 258
 259     if( var_Get( p_aout, "audio-device", &val ) < 0 )
 260     {
 261         /* Probe() has failed. */
 262         goto error;
 263     }
 264
 265     /* Now we need to setup our DirectSound play notification structure */
 266     p_aout->output.p_sys->p_notif =
 267         vlc_object_create( p_aout, sizeof(notification_thread_t) );
 268     p_aout->output.p_sys->p_notif->p_aout = p_aout;
 269
 270     /* Then create the notification events */
 271     for( i = 0; i < FRAMES_NUM; i++ )
 272         p_aout->output.p_sys->p_notif->p_events[i].hEventNotify =
 273             CreateEvent( NULL, FALSE, FALSE, NULL );
 274
 275     /* Open the device */
 276     if( val.i_int == AOUT_VAR_SPDIF )
 277     {
 278         p_aout->output.output.i_format = VLC_FOURCC('s','p','d','i');
 279
 280         /* Calculate the frame size in bytes */
 281         p_aout->output.i_nb_samples = A52_FRAME_NB;
 282         p_aout->output.output.i_bytes_per_frame = AOUT_SPDIF_SIZE;
 283         p_aout->output.output.i_frame_length = A52_FRAME_NB;
 284         p_aout->output.p_sys->i_frame_size =
 285             p_aout->output.output.i_bytes_per_frame;
 286
 287         if( CreateDSBuffer( p_aout, VLC_FOURCC('s','p','d','i'),
 288                             p_aout->output.output.i_physical_channels,
 289                             aout_FormatNbChannels( &p_aout->output.output ),
 290                             p_aout->output.output.i_rate,
 291                             p_aout->output.p_sys->i_frame_size, VLC_FALSE )
 292             != VLC_SUCCESS )
 293         {
 294             msg_Err( p_aout, "cannot open directx audio device" );
 295             free( p_aout->output.p_sys );
 296             return VLC_EGENERIC;
 297         }
 298
 299         aout_VolumeNoneInit( p_aout );
 300     }
 301     else
 302     {
 303         if( val.i_int == AOUT_VAR_5_1 )
 304         {
 305             p_aout->output.output.i_physical_channels
 306                 = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
 307                    | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT
 308                    | AOUT_CHAN_LFE;
 309         }
 310         else if( val.i_int == AOUT_VAR_3F2R )
 311         {
 312             p_aout->output.output.i_physical_channels
 313                 = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
 314                    | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT;
 315         }
 316         else if( val.i_int == AOUT_VAR_2F2R )
 317         {
 318             p_aout->output.output.i_physical_channels
 319                 = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
 320                    | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT;
 321         }
 322         else if( val.i_int == AOUT_VAR_MONO )
 323         {
 324             p_aout->output.output.i_physical_channels = AOUT_CHAN_CENTER;
 325         }
 326         else
 327         {
 328             p_aout->output.output.i_physical_channels
 329                 = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT;
 330         }
 331
 332         if( CreateDSBufferPCM( p_aout, &p_aout->output.output.i_format,
 333                                p_aout->output.output.i_physical_channels,
 334                                aout_FormatNbChannels( &p_aout->output.output ),
 335                                p_aout->output.output.i_rate, VLC_FALSE )
 336             != VLC_SUCCESS )
 337         {
 338             msg_Err( p_aout, "cannot open directx audio device" );
 339             free( p_aout->output.p_sys );
 340             return VLC_EGENERIC;
 341         }
 342
 343         /* Calculate the frame size in bytes */
 344         p_aout->output.i_nb_samples = FRAME_SIZE;
 345         aout_FormatPrepare( &p_aout->output.output );
 346         p_aout->output.p_sys->i_frame_size =
 347             FRAME_SIZE * p_aout->output.output.i_bytes_per_frame;
 348
 349         aout_VolumeSoftInit( p_aout );
 350     }
 351
 352     /* then launch the notification thread */
 353     msg_Dbg( p_aout, "creating DirectSoundThread" );
 354     if( vlc_thread_create( p_aout->output.p_sys->p_notif,
 355                            "DirectSound Notification Thread",
 356                            DirectSoundThread,
 357                            VLC_THREAD_PRIORITY_HIGHEST, VLC_FALSE ) )
 358     {
 359         msg_Err( p_aout, "cannot create DirectSoundThread" );
 360         goto error;
 361     }
 362
 363     vlc_object_attach( p_aout->output.p_sys->p_notif, p_aout );
 364
 365     return VLC_SUCCESS;
 366
 367  error:
 368     CloseAudio( VLC_OBJECT(p_aout) );
 369     return VLC_EGENERIC;
 370 }
 371
 372 /*****************************************************************************
 373  * Probe: probe the audio device for available formats and channels
 374  *****************************************************************************/
 375 static void Probe( aout_instance_t * p_aout )
 376 {
 377     vlc_value_t val, text;
 378     int i_format;
 379     unsigned int i_physical_channels;
 380     DWORD ui_speaker_config;
 381
 382     var_Create( p_aout, "audio-device", VLC_VAR_INTEGER | VLC_VAR_HASCHOICE );
 383     text.psz_string = _("Audio device");
 384     var_Change( p_aout, "audio-device", VLC_VAR_SETTEXT, &text, NULL );
 385
 386     /* Test for 5.1 support */
 387     i_physical_channels = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
 388                           AOUT_CHAN_CENTER | AOUT_CHAN_REARLEFT |
 389                           AOUT_CHAN_REARRIGHT | AOUT_CHAN_LFE;
 390     if( p_aout->output.output.i_physical_channels == i_physical_channels )
 391     {
 392         if( CreateDSBufferPCM( p_aout, &i_format, i_physical_channels, 6,
 393                                p_aout->output.output.i_rate, VLC_TRUE )
 394             == VLC_SUCCESS )
 395         {
 396             val.i_int = AOUT_VAR_5_1;
 397             text.psz_string = N_("5.1");
 398             var_Change( p_aout, "audio-device",
 399                         VLC_VAR_ADDCHOICE, &val, &text );
 400             msg_Dbg( p_aout, "device supports 5.1 channels" );
 401         }
 402     }
 403
 404     /* Test for 3 Front 2 Rear support */
 405     i_physical_channels = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
 406                           AOUT_CHAN_CENTER | AOUT_CHAN_REARLEFT |
 407                           AOUT_CHAN_REARRIGHT;
 408     if( p_aout->output.output.i_physical_channels == i_physical_channels )
 409     {
 410         if( CreateDSBufferPCM( p_aout, &i_format, i_physical_channels, 5,
 411                                p_aout->output.output.i_rate, VLC_TRUE )
 412             == VLC_SUCCESS )
 413         {
 414             val.i_int = AOUT_VAR_3F2R;
 415             text.psz_string = N_("3 Front 2 Rear");
 416             var_Change( p_aout, "audio-device",
 417                         VLC_VAR_ADDCHOICE, &val, &text );
 418             msg_Dbg( p_aout, "device supports 5 channels" );
 419         }
 420     }
 421
 422     /* Test for 2 Front 2 Rear support */
 423     i_physical_channels = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
 424                           AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT;
 425     if( ( p_aout->output.output.i_physical_channels & i_physical_channels )
 426         == i_physical_channels )
 427     {
 428         if( CreateDSBufferPCM( p_aout, &i_format, i_physical_channels, 4,
 429                                p_aout->output.output.i_rate, VLC_TRUE )
 430             == VLC_SUCCESS )
 431         {
 432             val.i_int = AOUT_VAR_2F2R;
 433             text.psz_string = N_("2 Front 2 Rear");
 434             var_Change( p_aout, "audio-device",
 435                         VLC_VAR_ADDCHOICE, &val, &text );
 436             msg_Dbg( p_aout, "device supports 4 channels" );
 437         }
 438     }
 439
 440     /* Test for stereo support */
 441     i_physical_channels = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT;
 442     if( CreateDSBufferPCM( p_aout, &i_format, i_physical_channels, 2,
 443                            p_aout->output.output.i_rate, VLC_TRUE )
 444         == VLC_SUCCESS )
 445     {
 446         val.i_int = AOUT_VAR_STEREO;
 447         text.psz_string = N_("Stereo");
 448         var_Change( p_aout, "audio-device", VLC_VAR_ADDCHOICE, &val, &text );
 449         var_Change( p_aout, "audio-device", VLC_VAR_SETDEFAULT, &val, NULL );
 450         msg_Dbg( p_aout, "device supports 2 channels" );
 451     }
 452
 453     /* Test for mono support */
 454     i_physical_channels = AOUT_CHAN_CENTER;
 455     if( CreateDSBufferPCM( p_aout, &i_format, i_physical_channels, 1,
 456                            p_aout->output.output.i_rate, VLC_TRUE )
 457         == VLC_SUCCESS )
 458     {
 459         val.i_int = AOUT_VAR_MONO;
 460         text.psz_string = N_("Mono");
 461         var_Change( p_aout, "audio-device", VLC_VAR_ADDCHOICE, &val, &text );
 462         msg_Dbg( p_aout, "device supports 1 channel" );
 463     }
 464
 465     /* Check the speaker configuration to determine which channel config should
 466      * be the default */
 467     if FAILED( IDirectSound_GetSpeakerConfig( p_aout->output.p_sys->p_dsobject,
 468                                               &ui_speaker_config ) )
 469     {
 470         ui_speaker_config = DSSPEAKER_STEREO;
 471     }
 472     switch( DSSPEAKER_CONFIG(ui_speaker_config) )
 473     {
 474     case DSSPEAKER_5POINT1:
 475         val.i_int = AOUT_VAR_5_1;
 476         break;
 477     case DSSPEAKER_QUAD:
 478         val.i_int = AOUT_VAR_2F2R;
 479         break;
 480 #if 0 /* Lots of people just get their settings wrong and complain that
 481        * this is a problem with VLC so just don't ever set mono by default. */
 482     case DSSPEAKER_MONO:
 483         val.i_int = AOUT_VAR_MONO;
 484         break;
 485 #endif
 486     case DSSPEAKER_SURROUND:
 487     case DSSPEAKER_STEREO:
 488     default:
 489         val.i_int = AOUT_VAR_STEREO;
 490         break;
 491     }
 492     var_Set( p_aout, "audio-device", val );
 493
 494     /* Test for SPDIF support */
 495     if ( AOUT_FMT_NON_LINEAR( &p_aout->output.output ) )
 496     {
 497         if( CreateDSBuffer( p_aout, VLC_FOURCC('s','p','d','i'),
 498                             p_aout->output.output.i_physical_channels,
 499                             aout_FormatNbChannels( &p_aout->output.output ),
 500                             p_aout->output.output.i_rate,
 501                             AOUT_SPDIF_SIZE, VLC_TRUE )
 502             == VLC_SUCCESS )
 503         {
 504             msg_Dbg( p_aout, "device supports A/52 over S/PDIF" );
 505             val.i_int = AOUT_VAR_SPDIF;
 506             text.psz_string = N_("A/52 over S/PDIF");
 507             var_Change( p_aout, "audio-device",
 508                         VLC_VAR_ADDCHOICE, &val, &text );
 509             if( config_GetInt( p_aout, "spdif" ) )
 510                 var_Set( p_aout, "audio-device", val );
 511         }
 512     }
 513
 514     var_Change( p_aout, "audio-device", VLC_VAR_CHOICESCOUNT, &val, NULL );
 515     if( val.i_int <= 0 )
 516     {
 517         /* Probe() has failed. */
 518         var_Destroy( p_aout, "audio-device" );
 519         return;
 520     }
 521
 522     var_AddCallback( p_aout, "audio-device", aout_ChannelsRestart, NULL );
 523
 524     val.b_bool = VLC_TRUE;
 525     var_Set( p_aout, "intf-change", val );
 526 }
 527
 528 /*****************************************************************************
 529  * Play: we'll start playing the directsound buffer here because at least here
 530  *       we know the first buffer has been put in the aout fifo and we also
 531  *       know its date.
 532  *****************************************************************************/
 533 static void Play( aout_instance_t *p_aout )
 534 {
 535     if( !p_aout->output.p_sys->b_playing )
 536     {
 537         aout_buffer_t *p_buffer;
 538
 539         p_aout->output.p_sys->b_playing = 1;
 540
 541         /* get the playing date of the first aout buffer */
 542         p_aout->output.p_sys->p_notif->start_date =
 543             aout_FifoFirstDate( p_aout, &p_aout->output.fifo );
 544
 545         /* fill in the first samples */
 546         p_buffer = aout_FifoPop( p_aout, &p_aout->output.fifo );
 547         FillBuffer( p_aout, 0, p_buffer );
 548
 549         /* wake up the audio output thread */
 550         SetEvent( p_aout->output.p_sys->p_notif->p_events[0].hEventNotify );
 551     }
 552 }
 553
 554 /*****************************************************************************
 555  * CloseAudio: close the audio device
 556  *****************************************************************************/
 557 static void CloseAudio( vlc_object_t *p_this )
 558 {
 559     aout_instance_t * p_aout = (aout_instance_t *)p_this;
 560
 561     msg_Dbg( p_aout, "CloseAudio" );
 562
 563     /* kill the position notification thread, if any */
 564     if( p_aout->output.p_sys->p_notif )
 565     {
 566         vlc_object_detach( p_aout->output.p_sys->p_notif );
 567         if( p_aout->output.p_sys->p_notif->b_thread )
 568         {
 569             p_aout->output.p_sys->p_notif->b_die = 1;
 570
 571             if( !p_aout->output.p_sys->b_playing )
 572                 /* wake up the audio thread */
 573                 SetEvent(
 574                     p_aout->output.p_sys->p_notif->p_events[0].hEventNotify );
 575
 576             vlc_thread_join( p_aout->output.p_sys->p_notif );
 577         }
 578         vlc_object_destroy( p_aout->output.p_sys->p_notif );
 579     }
 580
 581     /* release the secondary buffer */
 582     DestroyDSBuffer( p_aout );
 583
 584     /* finally release the DirectSound object */
 585     if( p_aout->output.p_sys->p_dsobject )
 586         IDirectSound_Release( p_aout->output.p_sys->p_dsobject );
 587
 588     /* free DSOUND.DLL */
 589     if( p_aout->output.p_sys->hdsound_dll )
 590        FreeLibrary( p_aout->output.p_sys->hdsound_dll );
 591
 592     if( p_aout->output.p_sys->pi_chan_table )
 593         free( p_aout->output.p_sys->pi_chan_table );
 594
 595     free( p_aout->output.p_sys );
 596 }
 597
 598 /*****************************************************************************
 599  * InitDirectSound: handle all the gory details of DirectSound initialisation
 600  *****************************************************************************/
 601 static int InitDirectSound( aout_instance_t *p_aout )
 602 {
 603     HRESULT (WINAPI *OurDirectSoundCreate)(LPGUID, LPDIRECTSOUND *, LPUNKNOWN);
 604
 605     p_aout->output.p_sys->hdsound_dll = LoadLibrary("DSOUND.DLL");
 606     if( p_aout->output.p_sys->hdsound_dll == NULL )
 607     {
 608         msg_Warn( p_aout, "cannot open DSOUND.DLL" );
 609         goto error;
 610     }
 611
 612     OurDirectSoundCreate = (void *)GetProcAddress(
 613                                            p_aout->output.p_sys->hdsound_dll,
 614                                            "DirectSoundCreate" );
 615     if( OurDirectSoundCreate == NULL )
 616     {
 617         msg_Warn( p_aout, "GetProcAddress FAILED" );
 618         goto error;
 619     }
 620
 621     /* Create the direct sound object */
 622     if FAILED( OurDirectSoundCreate( NULL, &p_aout->output.p_sys->p_dsobject,
 623                                      NULL ) )
 624     {
 625         msg_Warn( p_aout, "cannot create a direct sound device" );
 626         goto error;
 627     }
 628
 629     /* Set DirectSound Cooperative level, ie what control we want over Windows
 630      * sound device. In our case, DSSCL_EXCLUSIVE means that we can modify the
 631      * settings of the primary buffer, but also that only the sound of our
 632      * application will be hearable when it will have the focus.
 633      * !!! (this is not really working as intended yet because to set the
 634      * cooperative level you need the window handle of your application, and
 635      * I don't know of any easy way to get it. Especially since we might play
 636      * sound without any video, and so what window handle should we use ???
 637      * The hack for now is to use the Desktop window handle - it seems to be
 638      * working */
 639     if( IDirectSound_SetCooperativeLevel( p_aout->output.p_sys->p_dsobject,
 640                                           GetDesktopWindow(),
 641                                           DSSCL_EXCLUSIVE) )
 642     {
 643         msg_Warn( p_aout, "cannot set direct sound cooperative level" );
 644     }
 645
 646     return VLC_SUCCESS;
 647
 648  error:
 649     p_aout->output.p_sys->p_dsobject = NULL;
 650     if( p_aout->output.p_sys->hdsound_dll )
 651     {
 652         FreeLibrary( p_aout->output.p_sys->hdsound_dll );
 653         p_aout->output.p_sys->hdsound_dll = NULL;
 654     }
 655     return VLC_EGENERIC;
 656
 657 }
 658
 659 /*****************************************************************************
 660  * CreateDSBuffer: Creates a direct sound buffer of the required format.
 661  *****************************************************************************
 662  * This function creates the buffer we'll use to play audio.
 663  * In DirectSound there are two kinds of buffers:
 664  * - the primary buffer: which is the actual buffer that the soundcard plays
 665  * - the secondary buffer(s): these buffers are the one actually used by
 666  *    applications and DirectSound takes care of mixing them into the primary.
 667  *
 668  * Once you create a secondary buffer, you cannot change its format anymore so
 669  * you have to release the current one and create another.
 670  *****************************************************************************/
 671 static int CreateDSBuffer( aout_instance_t *p_aout, int i_format,
 672                            int i_channels, int i_nb_channels, int i_rate,
 673                            int i_bytes_per_frame, vlc_bool_t b_probe )
 674 {
 675     WAVEFORMATEXTENSIBLE waveformat;
 676     DSBUFFERDESC         dsbdesc;
 677     unsigned int         i;
 678
 679     /* First set the sound buffer format */
 680     waveformat.dwChannelMask = 0;
 681     for( i = 0; i < sizeof(pi_channels_in)/sizeof(uint32_t); i++ )
 682     {
 683         if( i_channels & pi_channels_in[i] )
 684             waveformat.dwChannelMask |= pi_channels_out[i];
 685     }
 686
 687     switch( i_format )
 688     {
 689     case VLC_FOURCC('s','p','d','i'):
 690         i_nb_channels = 2;
 691         /* To prevent channel re-ordering */
 692         waveformat.dwChannelMask = SPEAKER_FRONT_LEFT | SPEAKER_FRONT_RIGHT;
 693         waveformat.Format.wBitsPerSample = 16;
 694         waveformat.Samples.wValidBitsPerSample =
 695             waveformat.Format.wBitsPerSample;
 696         waveformat.Format.wFormatTag = WAVE_FORMAT_DOLBY_AC3_SPDIF;
 697         waveformat.SubFormat = _KSDATAFORMAT_SUBTYPE_DOLBY_AC3_SPDIF;
 698         break;
 699
 700     case VLC_FOURCC('f','l','3','2'):
 701         waveformat.Format.wBitsPerSample = sizeof(float) * 8;
 702         waveformat.Samples.wValidBitsPerSample =
 703             waveformat.Format.wBitsPerSample;
 704         waveformat.Format.wFormatTag = WAVE_FORMAT_IEEE_FLOAT;
 705         waveformat.SubFormat = _KSDATAFORMAT_SUBTYPE_IEEE_FLOAT;
 706         break;
 707
 708     case VLC_FOURCC('s','1','6','l'):
 709         waveformat.Format.wBitsPerSample = 16;
 710         waveformat.Samples.wValidBitsPerSample =
 711             waveformat.Format.wBitsPerSample;
 712         waveformat.Format.wFormatTag = WAVE_FORMAT_PCM;
 713         waveformat.SubFormat = _KSDATAFORMAT_SUBTYPE_PCM;
 714         break;
 715     }
 716
 717     waveformat.Format.nChannels = i_nb_channels;
 718     waveformat.Format.nSamplesPerSec = i_rate;
 719     waveformat.Format.nBlockAlign =
 720         waveformat.Format.wBitsPerSample / 8 * i_nb_channels;
 721     waveformat.Format.nAvgBytesPerSec =
 722         waveformat.Format.nSamplesPerSec * waveformat.Format.nBlockAlign;
 723
 724     /* Only use the new WAVE_FORMAT_EXTENSIBLE format for multichannel audio */
 725     if( i_nb_channels <= 2 )
 726     {
 727         waveformat.Format.cbSize = 0;
 728     }
 729     else
 730     {
 731         waveformat.Format.wFormatTag = WAVE_FORMAT_EXTENSIBLE;
 732         waveformat.Format.cbSize =
 733             sizeof(WAVEFORMATEXTENSIBLE) - sizeof(WAVEFORMATEX);
 734     }
 735
 736
 737     /* Then fill in the direct sound descriptor */
 738     memset(&dsbdesc, 0, sizeof(DSBUFFERDESC));
 739     dsbdesc.dwSize = sizeof(DSBUFFERDESC);
 740     dsbdesc.dwFlags = DSBCAPS_GETCURRENTPOSITION2/* Better position accuracy */
 741                     | DSBCAPS_CTRLPOSITIONNOTIFY     /* We need notification */
 742                     | DSBCAPS_GLOBALFOCUS       /* Allows background playing */
 743                     | DSBCAPS_LOCHARDWARE;      /* Needed for 5.1 on emu101k */
 744     dsbdesc.dwBufferBytes = FRAMES_NUM * i_bytes_per_frame;   /* buffer size */
 745     dsbdesc.lpwfxFormat = (WAVEFORMATEX *)&waveformat;
 746
 747     if FAILED( IDirectSound_CreateSoundBuffer(
 748                    p_aout->output.p_sys->p_dsobject, &dsbdesc,
 749                    &p_aout->output.p_sys->p_dsbuffer, NULL) )
 750     {
 751         /* Try without DSBCAPS_LOCHARDWARE */
 752         dsbdesc.dwFlags &= ~DSBCAPS_LOCHARDWARE;
 753         if FAILED( IDirectSound_CreateSoundBuffer(
 754                    p_aout->output.p_sys->p_dsobject, &dsbdesc,
 755                    &p_aout->output.p_sys->p_dsbuffer, NULL) )
 756         {
 757             return VLC_EGENERIC;
 758         }
 759         if( !b_probe ) msg_Dbg( p_aout, "couldn't use hardware sound buffer" );
 760     }
 761
 762     /* Stop here if we were just probing */
 763     if( b_probe )
 764     {
 765         IDirectSoundBuffer_Release( p_aout->output.p_sys->p_dsbuffer );
 766         p_aout->output.p_sys->p_dsbuffer = NULL;
 767         return VLC_SUCCESS;
 768     }
 769
 770     /* Backup the size of a frame */
 771     p_aout->output.p_sys->p_notif->i_frame_size = i_bytes_per_frame;
 772
 773     /* Now the secondary buffer is created, we need to setup its position
 774      * notification */
 775     for( i = 0; i < FRAMES_NUM; i++ )
 776     {
 777         p_aout->output.p_sys->p_notif->p_events[i].dwOffset = i *
 778             p_aout->output.p_sys->p_notif->i_frame_size;
 779
 780         p_aout->output.p_sys->p_notif->i_frame_status[i] = FRAME_EMPTY;
 781     }
 782
 783     /* Get the IDirectSoundNotify interface */
 784     if FAILED( IDirectSoundBuffer_QueryInterface(
 785                                 p_aout->output.p_sys->p_dsbuffer,
 786                                 &IID_IDirectSoundNotify,
 787                                 (LPVOID *)&p_aout->output.p_sys->p_dsnotify ) )
 788     {
 789         msg_Err( p_aout, "cannot get IDirectSoundNotify interface" );
 790         goto error;
 791     }
 792
 793     if FAILED( IDirectSoundNotify_SetNotificationPositions(
 794                                     p_aout->output.p_sys->p_dsnotify,
 795                                     FRAMES_NUM,
 796                                     p_aout->output.p_sys->p_notif->p_events ) )
 797     {
 798         msg_Err( p_aout, "cannot set position notification" );
 799         goto error;
 800     }
 801
 802     p_aout->output.p_sys->i_channel_mask = waveformat.dwChannelMask;
 803     CheckReordering( p_aout, i_nb_channels );
 804
 805     return VLC_SUCCESS;
 806
 807  error:
 808     DestroyDSBuffer( p_aout );
 809     return VLC_EGENERIC;
 810 }
 811
 812 /*****************************************************************************
 813  * CreateDSBufferPCM: creates a PCM direct sound buffer.
 814  *****************************************************************************
 815  * We first try to create a WAVE_FORMAT_IEEE_FLOAT buffer if supported by
 816  * the hardware, otherwise we create a WAVE_FORMAT_PCM buffer.
 817  ****************************************************************************/
 818 static int CreateDSBufferPCM( aout_instance_t *p_aout, int *i_format,
 819                               int i_channels, int i_nb_channels, int i_rate,
 820                               vlc_bool_t b_probe )
 821 {
 822     /* Float32 audio samples are not supported for 5.1 output on the emu101k */
 823
 824     if( i_nb_channels > 2 ||
 825         CreateDSBuffer( p_aout, VLC_FOURCC('f','l','3','2'),
 826                         i_channels, i_nb_channels, i_rate,
 827                         FRAME_SIZE * 4 * i_nb_channels, b_probe )
 828         != VLC_SUCCESS )
 829     {
 830         if ( CreateDSBuffer( p_aout, VLC_FOURCC('s','1','6','l'),
 831                              i_channels, i_nb_channels, i_rate,
 832                              FRAME_SIZE * 2 * i_nb_channels, b_probe )
 833              != VLC_SUCCESS )
 834         {
 835             return VLC_EGENERIC;
 836         }
 837         else
 838         {
 839             *i_format = VLC_FOURCC('s','1','6','l');
 840             return VLC_SUCCESS;
 841         }
 842     }
 843     else
 844     {
 845         *i_format = VLC_FOURCC('f','l','3','2');
 846         return VLC_SUCCESS;
 847     }
 848 }
 849
 850 /*****************************************************************************
 851  * DestroyDSBuffer
 852  *****************************************************************************
 853  * This function destroys the secondary buffer.
 854  *****************************************************************************/
 855 static void DestroyDSBuffer( aout_instance_t *p_aout )
 856 {
 857     if( p_aout->output.p_sys->p_dsnotify )
 858     {
 859         IDirectSoundNotify_Release( p_aout->output.p_sys->p_dsnotify );
 860         p_aout->output.p_sys->p_dsnotify = NULL;
 861     }
 862
 863     if( p_aout->output.p_sys->p_dsbuffer )
 864     {
 865         IDirectSoundBuffer_Release( p_aout->output.p_sys->p_dsbuffer );
 866         p_aout->output.p_sys->p_dsbuffer = NULL;
 867     }
 868 }
 869
 870 /*****************************************************************************
 871  * FillBuffer: Fill in one of the direct sound frame buffers.
 872  *****************************************************************************
 873  * Returns VLC_SUCCESS on success.
 874  *****************************************************************************/
 875 static int FillBuffer( aout_instance_t *p_aout, int i_frame,
 876                        aout_buffer_t *p_buffer )
 877 {
 878     notification_thread_t *p_notif = p_aout->output.p_sys->p_notif;
 879     void *p_write_position, *p_wrap_around;
 880     long l_bytes1, l_bytes2;
 881     HRESULT dsresult;
 882
 883     /* Before copying anything, we have to lock the buffer */
 884     dsresult = IDirectSoundBuffer_Lock(
 885                 p_aout->output.p_sys->p_dsbuffer,               /* DS buffer */
 886                 i_frame * p_notif->i_frame_size,             /* Start offset */
 887                 p_notif->i_frame_size,                    /* Number of bytes */
 888                 &p_write_position,                  /* Address of lock start */
 889                 &l_bytes1,       /* Count of bytes locked before wrap around */
 890                 &p_wrap_around,            /* Buffer adress (if wrap around) */
 891                 &l_bytes2,               /* Count of bytes after wrap around */
 892                 0 );                                                /* Flags */
 893     if( dsresult == DSERR_BUFFERLOST )
 894     {
 895         IDirectSoundBuffer_Restore( p_aout->output.p_sys->p_dsbuffer );
 896         dsresult = IDirectSoundBuffer_Lock(
 897                                p_aout->output.p_sys->p_dsbuffer,
 898                                i_frame * p_notif->i_frame_size,
 899                                p_notif->i_frame_size,
 900                                &p_write_position,
 901                                &l_bytes1,
 902                                &p_wrap_around,
 903                                &l_bytes2,
 904                                0 );
 905     }
 906     if( dsresult != DS_OK )
 907     {
 908         msg_Warn( p_notif, "cannot lock buffer" );
 909         if( p_buffer ) aout_BufferFree( p_buffer );
 910         return VLC_EGENERIC;
 911     }
 912
 913     if( p_buffer == NULL )
 914     {
 915         memset( p_write_position, 0, l_bytes1 );
 916     }
 917     else if( p_aout->output.p_sys->b_chan_reorder )
 918     {
 919         /* Do the channel reordering here */
 920
 921         if( p_aout->output.output.i_format ==  VLC_FOURCC('s','1','6','l') )
 922           InterleaveS16( (int16_t *)p_buffer->p_buffer,
 923                          (int16_t *)p_write_position,
 924                          p_aout->output.p_sys->pi_chan_table,
 925                          aout_FormatNbChannels( &p_aout->output.output ) );
 926         else
 927           InterleaveFloat32( (float *)p_buffer->p_buffer,
 928                              (float *)p_write_position,
 929                              p_aout->output.p_sys->pi_chan_table,
 930                              aout_FormatNbChannels( &p_aout->output.output ) );
 931
 932         aout_BufferFree( p_buffer );
 933     }
 934     else
 935     {
 936         p_aout->p_vlc->pf_memcpy( p_write_position, p_buffer->p_buffer,
 937                                   l_bytes1 );
 938         aout_BufferFree( p_buffer );
 939     }
 940
 941     /* Now the data has been copied, unlock the buffer */
 942     IDirectSoundBuffer_Unlock( p_aout->output.p_sys->p_dsbuffer,
 943                                p_write_position, l_bytes1,
 944                                p_wrap_around, l_bytes2 );
 945
 946     return VLC_SUCCESS;
 947 }
 948
 949 /*****************************************************************************
 950  * DirectSoundThread: this thread will capture play notification events.
 951  *****************************************************************************
 952  * We use this thread to emulate a callback mechanism. The thread probes for
 953  * event notification and fills up the DS secondary buffer when needed.
 954  *****************************************************************************/
 955 static void DirectSoundThread( notification_thread_t *p_notif )
 956 {
 957     HANDLE  notification_events[FRAMES_NUM];
 958     HRESULT dsresult;
 959     aout_instance_t *p_aout = p_notif->p_aout;
 960     int i, i_which_frame, i_last_frame, i_next_frame;
 961     mtime_t mtime;
 962     vlc_bool_t b_sleek;
 963
 964     for( i = 0; i < FRAMES_NUM; i++ )
 965         notification_events[i] = p_notif->p_events[i].hEventNotify;
 966
 967     /* We don't want any resampling when using S/PDIF output */
 968     b_sleek = p_aout->output.output.i_format == VLC_FOURCC('s','p','d','i');
 969
 970     /* Tell the main thread that we are ready */
 971     vlc_thread_ready( p_notif );
 972
 973     msg_Dbg( p_notif, "DirectSoundThread ready" );
 974
 975     /* Wait here until Play() is called */
 976     WaitForSingleObject( notification_events[0], INFINITE );
 977
 978     if( !p_notif->b_die )
 979     {
 980         mwait( p_notif->start_date - AOUT_PTS_TOLERANCE / 2 );
 981
 982         /* start playing the buffer */
 983         dsresult = IDirectSoundBuffer_Play( p_aout->output.p_sys->p_dsbuffer,
 984                                         0,                         /* Unused */
 985                                         0,                         /* Unused */
 986                                         DSBPLAY_LOOPING );          /* Flags */
 987         if( dsresult == DSERR_BUFFERLOST )
 988         {
 989             IDirectSoundBuffer_Restore( p_aout->output.p_sys->p_dsbuffer );
 990             dsresult = IDirectSoundBuffer_Play(
 991                                             p_aout->output.p_sys->p_dsbuffer,
 992                                             0,                     /* Unused */
 993                                             0,                     /* Unused */
 994                                             DSBPLAY_LOOPING );      /* Flags */
 995         }
 996         if( dsresult != DS_OK )
 997         {
 998             msg_Err( p_aout, "cannot start playing buffer" );
 999         }
1000     }
1001
1002     while( !p_notif->b_die )
1003     {
1004         aout_buffer_t *p_buffer;
1005         long l_latency;
1006
1007         /* wait for the position notification */
1008         i_which_frame = WaitForMultipleObjects( FRAMES_NUM,
1009                                                 notification_events, 0,
1010                                                 INFINITE ) - WAIT_OBJECT_0;
1011
1012         if( p_notif->b_die )
1013             break;
1014
1015         mtime = mdate();
1016
1017         /* We take into account the current latency */
1018         if SUCCEEDED( IDirectSoundBuffer_GetCurrentPosition(
1019                         p_aout->output.p_sys->p_dsbuffer,
1020                         &l_latency, NULL ) )
1021         {
1022             if( l_latency > (i_which_frame * FRAME_SIZE)
1023                   && l_latency < ((i_which_frame+1) * FRAME_SIZE) )
1024             {
1025                 l_latency = - ( l_latency /
1026                                 p_aout->output.output.i_bytes_per_frame %
1027                                 FRAME_SIZE );
1028             }
1029             else
1030             {
1031                 l_latency = FRAME_SIZE - ( l_latency /
1032                                       p_aout->output.output.i_bytes_per_frame %
1033                                       FRAME_SIZE );
1034             }
1035         }
1036         else
1037         {
1038             l_latency = 0;
1039         }
1040
1041         /* Mark last frame as empty */
1042         i_last_frame = (i_which_frame + FRAMES_NUM -1) % FRAMES_NUM;
1043         i_next_frame = (i_which_frame + 1) % FRAMES_NUM;
1044         p_notif->i_frame_status[i_last_frame] = FRAME_EMPTY;
1045
1046         /* Try to fill in as many frame buffers as possible */
1047         for( i = i_next_frame; (i % FRAMES_NUM) != i_which_frame; i++ )
1048         {
1049
1050             /* Check if frame buf is already filled */
1051             if( p_notif->i_frame_status[i % FRAMES_NUM] == FRAME_QUEUED )
1052                 continue;
1053
1054             p_buffer = aout_OutputNextBuffer( p_aout,
1055                 mtime + 1000000 / p_aout->output.output.i_rate *
1056                 ((i - i_next_frame + 1) * FRAME_SIZE + l_latency), b_sleek );
1057
1058             /* If there is no audio data available and we have some buffered
1059              * already, then just wait for the next time */
1060             if( !p_buffer && (i != i_next_frame) )
1061             {
1062                 //msg_Err( p_aout, "only %i frame buffers filled!",
1063                 //         i - i_next_frame );
1064                 break;
1065             }
1066
1067             if( FillBuffer( p_aout, (i%FRAMES_NUM), p_buffer )
1068                 != VLC_SUCCESS )
1069                 break;
1070
1071             /* Mark the frame buffer as QUEUED */
1072             p_notif->i_frame_status[i%FRAMES_NUM] = FRAME_QUEUED;
1073         }
1074
1075     }
1076
1077     /* make sure the buffer isn't playing */
1078     IDirectSoundBuffer_Stop( p_aout->output.p_sys->p_dsbuffer );
1079
1080     /* free the events */
1081     for( i = 0; i < FRAMES_NUM; i++ )
1082         CloseHandle( notification_events[i] );
1083
1084     msg_Dbg( p_notif, "DirectSoundThread exiting" );
1085 }
1086
1087 /*****************************************************************************
1088  * CheckReordering: Check if we need to do some channel re-ordering (the ac3
1089  *                  channel order is different from the one chosen by
1090  *                  Microsoft).
1091  *****************************************************************************/
1092 static void CheckReordering( aout_instance_t *p_aout, int i_nb_channels )
1093 {
1094     int i, j, k, l;
1095
1096 #define i_channel_mask p_aout->output.p_sys->i_channel_mask
1097 #define pi_chan_table p_aout->output.p_sys->pi_chan_table
1098
1099     p_aout->output.p_sys->b_chan_reorder = VLC_FALSE;
1100
1101     pi_chan_table = malloc( i_nb_channels * sizeof(int) );
1102     if( !pi_chan_table )
1103     {
1104         return;
1105     }
1106
1107     for( i = 0, j = 0;
1108          i < (int)(sizeof(pi_channels_out)/sizeof(uint32_t)); i++ )
1109     {
1110         if( i_channel_mask & pi_channels_out[i] )
1111         {
1112             for( k = 0, l = 0;
1113                  pi_channels_out[i] != pi_channels_ordered[k]; k++ )
1114             {
1115                 if( i_channel_mask & pi_channels_ordered[k] )
1116                 {
1117                     l++;
1118                 }
1119             }
1120
1121             pi_chan_table[j] = l;
1122
1123             j++;
1124         }
1125     }
1126
1127     for( i = 0; i < i_nb_channels; i++ )
1128     {
1129         if( pi_chan_table[i] != i )
1130         {
1131             p_aout->output.p_sys->b_chan_reorder = VLC_TRUE;
1132         }
1133     }
1134
1135     if( p_aout->output.p_sys->b_chan_reorder )
1136     {
1137         msg_Dbg( p_aout, "channel reordering needed" );
1138     }
1139
1140 #undef pi_chan_table
1141 #undef waveformat
1142 }
1143
1144 /*****************************************************************************
1145  * InterleaveFloat32/S16: change the channel order to the Microsoft one.
1146  *****************************************************************************/
1147 static void InterleaveFloat32( float *p_buf, float *p_buf_out,
1148                                int *pi_chan_table, int i_nb_channels )
1149 {
1150     int i, j;
1151
1152     for( i = 0; i < FRAME_SIZE; i++ )
1153     {
1154         for( j = 0; j < i_nb_channels; j++ )
1155         {
1156             p_buf_out[i*i_nb_channels + pi_chan_table[j]] =
1157                 p_buf[i*i_nb_channels + j];
1158         }
1159     }
1160 }
1161
1162 static void InterleaveS16( int16_t *p_buf, int16_t *p_buf_out,
1163                            int *pi_chan_table, int i_nb_channels )
1164 {
1165     int i, j;
1166
1167     for( i = 0; i < FRAME_SIZE; i++ )
1168     {
1169         for( j = 0; j < i_nb_channels; j++ )
1170         {
1171             p_buf_out[ i*i_nb_channels + pi_chan_table[j]] =
1172                 p_buf[i*i_nb_channels + j];
1173         }
1174     }
1175 }