libao2/ao_dsound.c

   1 /*
   2  * Windows DirectSound interface
   3  *
   4  * Copyright (c) 2004 Gabor Szecsi <deje@miki.hu>
   5  *
   6  * This file is part of MPlayer.
   7  *
   8  * MPlayer is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * MPlayer 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 General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with MPlayer; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22
  23 /**
  24 \todo verify/extend multichannel support
  25 */
  26
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <windows.h>
  31 #define DIRECTSOUND_VERSION 0x0600
  32 #include <dsound.h>
  33 #include <math.h>
  34
  35 #include "config.h"
  36 #include "libaf/af_format.h"
  37 #include "audio_out.h"
  38 #include "audio_out_internal.h"
  39 #include "mp_msg.h"
  40 #include "libvo/fastmemcpy.h"
  41 #include "osdep/timer.h"
  42 #include "subopt-helper.h"
  43
  44
  45 static const ao_info_t info =
  46 {
  47         "Windows DirectSound audio output",
  48         "dsound",
  49         "Gabor Szecsi <deje@miki.hu>",
  50         ""
  51 };
  52
  53 LIBAO_EXTERN(dsound)
  54
  55 /**
  56 \todo use the definitions from the win32 api headers when they define these
  57 */
  58 #define WAVE_FORMAT_IEEE_FLOAT 0x0003
  59 #define WAVE_FORMAT_DOLBY_AC3_SPDIF 0x0092
  60 #define WAVE_FORMAT_EXTENSIBLE 0xFFFE
  61
  62 static const GUID KSDATAFORMAT_SUBTYPE_PCM = {0x1,0x0000,0x0010, {0x80,0x00,0x00,0xaa,0x00,0x38,0x9b,0x71}};
  63
  64 #define SPEAKER_FRONT_LEFT             0x1
  65 #define SPEAKER_FRONT_RIGHT            0x2
  66 #define SPEAKER_FRONT_CENTER           0x4
  67 #define SPEAKER_LOW_FREQUENCY          0x8
  68 #define SPEAKER_BACK_LEFT              0x10
  69 #define SPEAKER_BACK_RIGHT             0x20
  70 #define SPEAKER_FRONT_LEFT_OF_CENTER   0x40
  71 #define SPEAKER_FRONT_RIGHT_OF_CENTER  0x80
  72 #define SPEAKER_BACK_CENTER            0x100
  73 #define SPEAKER_SIDE_LEFT              0x200
  74 #define SPEAKER_SIDE_RIGHT             0x400
  75 #define SPEAKER_TOP_CENTER             0x800
  76 #define SPEAKER_TOP_FRONT_LEFT         0x1000
  77 #define SPEAKER_TOP_FRONT_CENTER       0x2000
  78 #define SPEAKER_TOP_FRONT_RIGHT        0x4000
  79 #define SPEAKER_TOP_BACK_LEFT          0x8000
  80 #define SPEAKER_TOP_BACK_CENTER        0x10000
  81 #define SPEAKER_TOP_BACK_RIGHT         0x20000
  82 #define SPEAKER_RESERVED               0x80000000
  83
  84 #if 0
  85 #define DSSPEAKER_HEADPHONE         0x00000001
  86 #define DSSPEAKER_MONO              0x00000002
  87 #define DSSPEAKER_QUAD              0x00000003
  88 #define DSSPEAKER_STEREO            0x00000004
  89 #define DSSPEAKER_SURROUND          0x00000005
  90 #define DSSPEAKER_5POINT1           0x00000006
  91 #endif
  92
  93 #ifndef _WAVEFORMATEXTENSIBLE_
  94 typedef struct {
  95     WAVEFORMATEX    Format;
  96     union {
  97         WORD wValidBitsPerSample;       /* bits of precision  */
  98         WORD wSamplesPerBlock;          /* valid if wBitsPerSample==0 */
  99         WORD wReserved;                 /* If neither applies, set to zero. */
 100     } Samples;
 101     DWORD           dwChannelMask;      /* which channels are */
 102                                         /* present in stream  */
 103     GUID            SubFormat;
 104 } WAVEFORMATEXTENSIBLE, *PWAVEFORMATEXTENSIBLE;
 105 #endif
 106
 107 static const int channel_mask[] = {
 108   SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_RIGHT  | SPEAKER_LOW_FREQUENCY,
 109   SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_RIGHT  | SPEAKER_BACK_LEFT    | SPEAKER_BACK_RIGHT,
 110   SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_RIGHT  | SPEAKER_BACK_LEFT    | SPEAKER_BACK_RIGHT   | SPEAKER_LOW_FREQUENCY,
 111   SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_CENTER | SPEAKER_FRONT_RIGHT  | SPEAKER_BACK_LEFT    | SPEAKER_BACK_RIGHT     | SPEAKER_LOW_FREQUENCY
 112 };
 113
 114 static HINSTANCE hdsound_dll = NULL;      ///handle to the dll
 115 static LPDIRECTSOUND hds = NULL;          ///direct sound object
 116 static LPDIRECTSOUNDBUFFER hdspribuf = NULL; ///primary direct sound buffer
 117 static LPDIRECTSOUNDBUFFER hdsbuf = NULL; ///secondary direct sound buffer (stream buffer)
 118 static int buffer_size = 0;               ///size in bytes of the direct sound buffer
 119 static int write_offset = 0;              ///offset of the write cursor in the direct sound buffer
 120 static int min_free_space = 0;            ///if the free space is below this value get_space() will return 0
 121                                           ///there will always be at least this amout of free space to prevent
 122                                           ///get_space() from returning wrong values when buffer is 100% full.
 123                                           ///will be replaced with nBlockAlign in init()
 124 static int device_num = 0;                ///wanted device number
 125 static GUID device;                       ///guid of the device
 126
 127 /***************************************************************************************/
 128
 129 /**
 130 \brief output error message
 131 \param err error code
 132 \return string with the error message
 133 */
 134 static char * dserr2str(int err)
 135 {
 136         switch (err) {
 137                 case DS_OK: return "DS_OK";
 138                 case DS_NO_VIRTUALIZATION: return "DS_NO_VIRTUALIZATION";
 139                 case DSERR_ALLOCATED: return "DS_NO_VIRTUALIZATION";
 140                 case DSERR_CONTROLUNAVAIL: return "DSERR_CONTROLUNAVAIL";
 141                 case DSERR_INVALIDPARAM: return "DSERR_INVALIDPARAM";
 142                 case DSERR_INVALIDCALL: return "DSERR_INVALIDCALL";
 143                 case DSERR_GENERIC: return "DSERR_GENERIC";
 144                 case DSERR_PRIOLEVELNEEDED: return "DSERR_PRIOLEVELNEEDED";
 145                 case DSERR_OUTOFMEMORY: return "DSERR_OUTOFMEMORY";
 146                 case DSERR_BADFORMAT: return "DSERR_BADFORMAT";
 147                 case DSERR_UNSUPPORTED: return "DSERR_UNSUPPORTED";
 148                 case DSERR_NODRIVER: return "DSERR_NODRIVER";
 149                 case DSERR_ALREADYINITIALIZED: return "DSERR_ALREADYINITIALIZED";
 150                 case DSERR_NOAGGREGATION: return "DSERR_NOAGGREGATION";
 151                 case DSERR_BUFFERLOST: return "DSERR_BUFFERLOST";
 152                 case DSERR_OTHERAPPHASPRIO: return "DSERR_OTHERAPPHASPRIO";
 153                 case DSERR_UNINITIALIZED: return "DSERR_UNINITIALIZED";
 154                 case DSERR_NOINTERFACE: return "DSERR_NOINTERFACE";
 155                 case DSERR_ACCESSDENIED: return "DSERR_ACCESSDENIED";
 156                 default: return "unknown";
 157         }
 158 }
 159
 160 /**
 161 \brief uninitialize direct sound
 162 */
 163 static void UninitDirectSound(void)
 164 {
 165     // finally release the DirectSound object
 166     if (hds) {
 167         IDirectSound_Release(hds);
 168         hds = NULL;
 169     }
 170     // free DSOUND.DLL
 171     if (hdsound_dll) {
 172         FreeLibrary(hdsound_dll);
 173         hdsound_dll = NULL;
 174     }
 175         mp_msg(MSGT_AO, MSGL_V, "ao_dsound: DirectSound uninitialized\n");
 176 }
 177
 178 /**
 179 \brief print the commandline help
 180 */
 181 static void print_help(void)
 182 {
 183   mp_msg(MSGT_AO, MSGL_FATAL,
 184            "\n-ao dsound commandline help:\n"
 185            "Example: mplayer -ao dsound:device=1\n"
 186            "  sets 1st device\n"
 187            "\nOptions:\n"
 188            "  device=<device-number>\n"
 189            "    Sets device number, use -v to get a list\n");
 190 }
 191
 192
 193 /**
 194 \brief enumerate direct sound devices
 195 \return TRUE to continue with the enumeration
 196 */
 197 static BOOL CALLBACK DirectSoundEnum(LPGUID guid,LPCSTR desc,LPCSTR module,LPVOID context)
 198 {
 199     int* device_index=context;
 200     mp_msg(MSGT_AO, MSGL_V,"%i %s ",*device_index,desc);
 201     if(device_num==*device_index){
 202         mp_msg(MSGT_AO, MSGL_V,"<--");
 203         if(guid){
 204             memcpy(&device,guid,sizeof(GUID));
 205         }
 206     }
 207     mp_msg(MSGT_AO, MSGL_V,"\n");
 208     (*device_index)++;
 209     return TRUE;
 210 }
 211
 212
 213 /**
 214 \brief initilize direct sound
 215 \return 0 if error, 1 if ok
 216 */
 217 static int InitDirectSound(void)
 218 {
 219         DSCAPS dscaps;
 220
 221         // initialize directsound
 222     HRESULT (WINAPI *OurDirectSoundCreate)(LPGUID, LPDIRECTSOUND *, LPUNKNOWN);
 223         HRESULT (WINAPI *OurDirectSoundEnumerate)(LPDSENUMCALLBACKA, LPVOID);
 224         int device_index=0;
 225         const opt_t subopts[] = {
 226           {"device", OPT_ARG_INT, &device_num,NULL},
 227           {NULL}
 228         };
 229         if (subopt_parse(ao_subdevice, subopts) != 0) {
 230                 print_help();
 231                 return 0;
 232         }
 233
 234         hdsound_dll = LoadLibrary("DSOUND.DLL");
 235         if (hdsound_dll == NULL) {
 236                 mp_msg(MSGT_AO, MSGL_ERR, "ao_dsound: cannot load DSOUND.DLL\n");
 237                 return 0;
 238         }
 239         OurDirectSoundCreate = (void*)GetProcAddress(hdsound_dll, "DirectSoundCreate");
 240         OurDirectSoundEnumerate = (void*)GetProcAddress(hdsound_dll, "DirectSoundEnumerateA");
 241
 242         if (OurDirectSoundCreate == NULL || OurDirectSoundEnumerate == NULL) {
 243                 mp_msg(MSGT_AO, MSGL_ERR, "ao_dsound: GetProcAddress FAILED\n");
 244                 FreeLibrary(hdsound_dll);
 245                 return 0;
 246         }
 247
 248         // Enumerate all directsound devices
 249         mp_msg(MSGT_AO, MSGL_V,"ao_dsound: Output Devices:\n");
 250         OurDirectSoundEnumerate(DirectSoundEnum,&device_index);
 251
 252         // Create the direct sound object
 253         if FAILED(OurDirectSoundCreate((device_num)?&device:NULL, &hds, NULL )) {
 254                 mp_msg(MSGT_AO, MSGL_ERR, "ao_dsound: cannot create a DirectSound device\n");
 255                 FreeLibrary(hdsound_dll);
 256                 return 0;
 257         }
 258
 259         /* Set DirectSound Cooperative level, ie what control we want over Windows
 260          * sound device. In our case, DSSCL_EXCLUSIVE means that we can modify the
 261          * settings of the primary buffer, but also that only the sound of our
 262          * application will be hearable when it will have the focus.
 263          * !!! (this is not really working as intended yet because to set the
 264          * cooperative level you need the window handle of your application, and
 265          * I don't know of any easy way to get it. Especially since we might play
 266          * sound without any video, and so what window handle should we use ???
 267          * The hack for now is to use the Desktop window handle - it seems to be
 268          * working */
 269         if (IDirectSound_SetCooperativeLevel(hds, GetDesktopWindow(), DSSCL_EXCLUSIVE)) {
 270                 mp_msg(MSGT_AO, MSGL_ERR, "ao_dsound: cannot set direct sound cooperative level\n");
 271                 IDirectSound_Release(hds);
 272                 FreeLibrary(hdsound_dll);
 273                 return 0;
 274         }
 275         mp_msg(MSGT_AO, MSGL_V, "ao_dsound: DirectSound initialized\n");
 276
 277         memset(&dscaps, 0, sizeof(DSCAPS));
 278         dscaps.dwSize = sizeof(DSCAPS);
 279         if (DS_OK == IDirectSound_GetCaps(hds, &dscaps)) {
 280                 if (dscaps.dwFlags & DSCAPS_EMULDRIVER) mp_msg(MSGT_AO, MSGL_V, "ao_dsound: DirectSound is emulated, waveOut may give better performance\n");
 281         } else {
 282                 mp_msg(MSGT_AO, MSGL_V, "ao_dsound: cannot get device capabilities\n");
 283         }
 284
 285         return 1;
 286 }
 287
 288 /**
 289 \brief destroy the direct sound buffer
 290 */
 291 static void DestroyBuffer(void)
 292 {
 293         if (hdsbuf) {
 294                 IDirectSoundBuffer_Release(hdsbuf);
 295                 hdsbuf = NULL;
 296         }
 297         if (hdspribuf) {
 298                 IDirectSoundBuffer_Release(hdspribuf);
 299                 hdspribuf = NULL;
 300         }
 301 }
 302
 303 /**
 304 \brief fill sound buffer
 305 \param data pointer to the sound data to copy
 306 \param len length of the data to copy in bytes
 307 \return number of copyed bytes
 308 */
 309 static int write_buffer(unsigned char *data, int len)
 310 {
 311   HRESULT res;
 312   LPVOID lpvPtr1;
 313   DWORD dwBytes1;
 314   LPVOID lpvPtr2;
 315   DWORD dwBytes2;
 316
 317   // Lock the buffer
 318   res = IDirectSoundBuffer_Lock(hdsbuf,write_offset, len, &lpvPtr1, &dwBytes1, &lpvPtr2, &dwBytes2, 0);
 319   // If the buffer was lost, restore and retry lock.
 320   if (DSERR_BUFFERLOST == res)
 321   {
 322     IDirectSoundBuffer_Restore(hdsbuf);
 323         res = IDirectSoundBuffer_Lock(hdsbuf,write_offset, len, &lpvPtr1, &dwBytes1, &lpvPtr2, &dwBytes2, 0);
 324   }
 325
 326
 327   if (SUCCEEDED(res))
 328   {
 329         if( (ao_data.channels == 6) && !AF_FORMAT_IS_AC3(ao_data.format) ) {
 330             // reorder channels while writing to pointers.
 331             // it's this easy because buffer size and len are always
 332             // aligned to multiples of channels*bytespersample
 333             // there's probably some room for speed improvements here
 334             const int chantable[6] = {0, 1, 4, 5, 2, 3}; // reorder "matrix"
 335             int i, j;
 336             int numsamp,sampsize;
 337
 338             sampsize = af_fmt2bits(ao_data.format)>>3; // bytes per sample
 339             numsamp = dwBytes1 / (ao_data.channels * sampsize);  // number of samples for each channel in this buffer
 340
 341             for( i = 0; i < numsamp; i++ ) for( j = 0; j < ao_data.channels; j++ ) {
 342                 memcpy((char*)lpvPtr1+(i*ao_data.channels*sampsize)+(chantable[j]*sampsize),data+(i*ao_data.channels*sampsize)+(j*sampsize),sampsize);
 343             }
 344
 345             if (NULL != lpvPtr2 )
 346             {
 347                 numsamp = dwBytes2 / (ao_data.channels * sampsize);
 348                 for( i = 0; i < numsamp; i++ ) for( j = 0; j < ao_data.channels; j++ ) {
 349                     memcpy((char*)lpvPtr2+(i*ao_data.channels*sampsize)+(chantable[j]*sampsize),data+dwBytes1+(i*ao_data.channels*sampsize)+(j*sampsize),sampsize);
 350                 }
 351             }
 352
 353             write_offset+=dwBytes1+dwBytes2;
 354             if(write_offset>=buffer_size)write_offset=dwBytes2;
 355         } else {
 356             // Write to pointers without reordering.
 357         fast_memcpy(lpvPtr1,data,dwBytes1);
 358     if (NULL != lpvPtr2 )fast_memcpy(lpvPtr2,data+dwBytes1,dwBytes2);
 359         write_offset+=dwBytes1+dwBytes2;
 360     if(write_offset>=buffer_size)write_offset=dwBytes2;
 361         }
 362
 363    // Release the data back to DirectSound.
 364     res = IDirectSoundBuffer_Unlock(hdsbuf,lpvPtr1,dwBytes1,lpvPtr2,dwBytes2);
 365     if (SUCCEEDED(res))
 366     {
 367           // Success.
 368           DWORD status;
 369           IDirectSoundBuffer_GetStatus(hdsbuf, &status);
 370       if (!(status & DSBSTATUS_PLAYING)){
 371             res = IDirectSoundBuffer_Play(hdsbuf, 0, 0, DSBPLAY_LOOPING);
 372           }
 373           return dwBytes1+dwBytes2;
 374     }
 375   }
 376   // Lock, Unlock, or Restore failed.
 377   return 0;
 378 }
 379
 380 /***************************************************************************************/
 381
 382 /**
 383 \brief handle control commands
 384 \param cmd command
 385 \param arg argument
 386 \return CONTROL_OK or -1 in case the command can't be handled
 387 */
 388 static int control(int cmd, void *arg)
 389 {
 390         DWORD volume;
 391         switch (cmd) {
 392                 case AOCONTROL_GET_VOLUME: {
 393                         ao_control_vol_t* vol = (ao_control_vol_t*)arg;
 394                         IDirectSoundBuffer_GetVolume(hdsbuf, &volume);
 395                         vol->left = vol->right = pow(10.0, (float)(volume+10000) / 5000.0);
 396                         //printf("ao_dsound: volume: %f\n",vol->left);
 397                         return CONTROL_OK;
 398                 }
 399                 case AOCONTROL_SET_VOLUME: {
 400                         ao_control_vol_t* vol = (ao_control_vol_t*)arg;
 401                         volume = (DWORD)(log10(vol->right) * 5000.0) - 10000;
 402                         IDirectSoundBuffer_SetVolume(hdsbuf, volume);
 403                         //printf("ao_dsound: volume: %f\n",vol->left);
 404                         return CONTROL_OK;
 405                 }
 406         }
 407         return -1;
 408 }
 409
 410 /**
 411 \brief setup sound device
 412 \param rate samplerate
 413 \param channels number of channels
 414 \param format format
 415 \param flags unused
 416 \return 1=success 0=fail
 417 */
 418 static int init(int rate, int channels, int format, int flags)
 419 {
 420     int res;
 421         if (!InitDirectSound()) return 0;
 422
 423         // ok, now create the buffers
 424         WAVEFORMATEXTENSIBLE wformat;
 425         DSBUFFERDESC dsbpridesc;
 426         DSBUFFERDESC dsbdesc;
 427
 428         //check if the channel count and format is supported in general
 429         if (channels > 6) {
 430                 UninitDirectSound();
 431                 mp_msg(MSGT_AO, MSGL_ERR, "ao_dsound: 8 channel audio not yet supported\n");
 432                 return 0;
 433         }
 434
 435         if (AF_FORMAT_IS_AC3(format))
 436                 format = AF_FORMAT_AC3_NE;
 437         switch(format){
 438                 case AF_FORMAT_AC3_NE:
 439                 case AF_FORMAT_S24_LE:
 440                 case AF_FORMAT_S16_LE:
 441                 case AF_FORMAT_U8:
 442                         break;
 443                 default:
 444                         mp_msg(MSGT_AO, MSGL_V,"ao_dsound: format %s not supported defaulting to Signed 16-bit Little-Endian\n",af_fmt2str_short(format));
 445                         format=AF_FORMAT_S16_LE;
 446         }
 447         //fill global ao_data
 448         ao_data.channels = channels;
 449         ao_data.samplerate = rate;
 450         ao_data.format = format;
 451         ao_data.bps = channels * rate * (af_fmt2bits(format)>>3);
 452         if(ao_data.buffersize==-1) ao_data.buffersize = ao_data.bps; // space for 1 sec
 453         mp_msg(MSGT_AO, MSGL_V,"ao_dsound: Samplerate:%iHz Channels:%i Format:%s\n", rate, channels, af_fmt2str_short(format));
 454         mp_msg(MSGT_AO, MSGL_V,"ao_dsound: Buffersize:%d bytes (%d msec)\n", ao_data.buffersize, ao_data.buffersize / ao_data.bps * 1000);
 455
 456         //fill waveformatex
 457         ZeroMemory(&wformat, sizeof(WAVEFORMATEXTENSIBLE));
 458         wformat.Format.cbSize          = (channels > 2) ? sizeof(WAVEFORMATEXTENSIBLE)-sizeof(WAVEFORMATEX) : 0;
 459         wformat.Format.nChannels       = channels;
 460         wformat.Format.nSamplesPerSec  = rate;
 461         if (AF_FORMAT_IS_AC3(format)) {
 462                 wformat.Format.wFormatTag      = WAVE_FORMAT_DOLBY_AC3_SPDIF;
 463                 wformat.Format.wBitsPerSample  = 16;
 464                 wformat.Format.nBlockAlign     = 4;
 465         } else {
 466                 wformat.Format.wFormatTag      = (channels > 2) ? WAVE_FORMAT_EXTENSIBLE : WAVE_FORMAT_PCM;
 467                 wformat.Format.wBitsPerSample  = af_fmt2bits(format);
 468                 wformat.Format.nBlockAlign     = wformat.Format.nChannels * (wformat.Format.wBitsPerSample >> 3);
 469         }
 470
 471         // fill in primary sound buffer descriptor
 472         memset(&dsbpridesc, 0, sizeof(DSBUFFERDESC));
 473         dsbpridesc.dwSize = sizeof(DSBUFFERDESC);
 474         dsbpridesc.dwFlags       = DSBCAPS_PRIMARYBUFFER;
 475         dsbpridesc.dwBufferBytes = 0;
 476         dsbpridesc.lpwfxFormat   = NULL;
 477
 478
 479         // fill in the secondary sound buffer (=stream buffer) descriptor
 480         memset(&dsbdesc, 0, sizeof(DSBUFFERDESC));
 481         dsbdesc.dwSize = sizeof(DSBUFFERDESC);
 482         dsbdesc.dwFlags = DSBCAPS_GETCURRENTPOSITION2 /** Better position accuracy */
 483                         | DSBCAPS_GLOBALFOCUS         /** Allows background playing */
 484                         | DSBCAPS_CTRLVOLUME;         /** volume control enabled */
 485
 486         if (channels > 2) {
 487                 wformat.dwChannelMask = channel_mask[channels - 3];
 488                 wformat.SubFormat = KSDATAFORMAT_SUBTYPE_PCM;
 489                 wformat.Samples.wValidBitsPerSample = wformat.Format.wBitsPerSample;
 490                 // Needed for 5.1 on emu101k - shit soundblaster
 491                 dsbdesc.dwFlags |= DSBCAPS_LOCHARDWARE;
 492         }
 493         wformat.Format.nAvgBytesPerSec = wformat.Format.nSamplesPerSec * wformat.Format.nBlockAlign;
 494
 495         dsbdesc.dwBufferBytes = ao_data.buffersize;
 496         dsbdesc.lpwfxFormat = (WAVEFORMATEX *)&wformat;
 497         buffer_size = dsbdesc.dwBufferBytes;
 498         write_offset = 0;
 499         min_free_space = wformat.Format.nBlockAlign;
 500         ao_data.outburst = wformat.Format.nBlockAlign * 512;
 501
 502         // create primary buffer and set its format
 503
 504         res = IDirectSound_CreateSoundBuffer( hds, &dsbpridesc, &hdspribuf, NULL );
 505         if ( res != DS_OK ) {
 506                 UninitDirectSound();
 507                 mp_msg(MSGT_AO, MSGL_ERR,"ao_dsound: cannot create primary buffer (%s)\n", dserr2str(res));
 508                 return 0;
 509         }
 510         res = IDirectSoundBuffer_SetFormat( hdspribuf, (WAVEFORMATEX *)&wformat );
 511         if ( res != DS_OK ) mp_msg(MSGT_AO, MSGL_WARN,"ao_dsound: cannot set primary buffer format (%s), using standard setting (bad quality)", dserr2str(res));
 512
 513         mp_msg(MSGT_AO, MSGL_V, "ao_dsound: primary buffer created\n");
 514
 515         // now create the stream buffer
 516
 517         res = IDirectSound_CreateSoundBuffer(hds, &dsbdesc, &hdsbuf, NULL);
 518         if (res != DS_OK) {
 519                 if (dsbdesc.dwFlags & DSBCAPS_LOCHARDWARE) {
 520                         // Try without DSBCAPS_LOCHARDWARE
 521                         dsbdesc.dwFlags &= ~DSBCAPS_LOCHARDWARE;
 522                         res = IDirectSound_CreateSoundBuffer(hds, &dsbdesc, &hdsbuf, NULL);
 523                 }
 524                 if (res != DS_OK) {
 525                         UninitDirectSound();
 526                         mp_msg(MSGT_AO, MSGL_ERR, "ao_dsound: cannot create secondary (stream)buffer (%s)\n", dserr2str(res));
 527                         return 0;
 528                 }
 529         }
 530         mp_msg(MSGT_AO, MSGL_V, "ao_dsound: secondary (stream)buffer created\n");
 531         return 1;
 532 }
 533
 534
 535
 536 /**
 537 \brief stop playing and empty buffers (for seeking/pause)
 538 */
 539 static void reset(void)
 540 {
 541         IDirectSoundBuffer_Stop(hdsbuf);
 542         // reset directsound buffer
 543         IDirectSoundBuffer_SetCurrentPosition(hdsbuf, 0);
 544         write_offset=0;
 545 }
 546
 547 /**
 548 \brief stop playing, keep buffers (for pause)
 549 */
 550 static void audio_pause(void)
 551 {
 552         IDirectSoundBuffer_Stop(hdsbuf);
 553 }
 554
 555 /**
 556 \brief resume playing, after audio_pause()
 557 */
 558 static void audio_resume(void)
 559 {
 560         IDirectSoundBuffer_Play(hdsbuf, 0, 0, DSBPLAY_LOOPING);
 561 }
 562
 563 /**
 564 \brief close audio device
 565 \param immed stop playback immediately
 566 */
 567 static void uninit(int immed)
 568 {
 569         if(immed)reset();
 570         else{
 571                 DWORD status;
 572                 IDirectSoundBuffer_Play(hdsbuf, 0, 0, 0);
 573                 while(!IDirectSoundBuffer_GetStatus(hdsbuf,&status) && (status&DSBSTATUS_PLAYING))
 574                         usec_sleep(20000);
 575         }
 576         DestroyBuffer();
 577         UninitDirectSound();
 578 }
 579
 580 /**
 581 \brief find out how many bytes can be written into the audio buffer without
 582 \return free space in bytes, has to return 0 if the buffer is almost full
 583 */
 584 static int get_space(void)
 585 {
 586         int space;
 587         DWORD play_offset;
 588         IDirectSoundBuffer_GetCurrentPosition(hdsbuf,&play_offset,NULL);
 589         space=buffer_size-(write_offset-play_offset);
 590         //                |                                                      | <-- const --> |                |                 |
 591         //                buffer start                                           play_cursor     write_cursor     write_offset      buffer end
 592         // play_cursor is the actual postion of the play cursor
 593         // write_cursor is the position after which it is assumed to be save to write data
 594         // write_offset is the postion where we actually write the data to
 595         if(space > buffer_size)space -= buffer_size; // write_offset < play_offset
 596         if(space < min_free_space)return 0;
 597         return space-min_free_space;
 598 }
 599
 600 /**
 601 \brief play 'len' bytes of 'data'
 602 \param data pointer to the data to play
 603 \param len size in bytes of the data buffer, gets rounded down to outburst*n
 604 \param flags currently unused
 605 \return number of played bytes
 606 */
 607 static int play(void* data, int len, int flags)
 608 {
 609         DWORD play_offset;
 610         int space;
 611
 612         // make sure we have enough space to write data
 613         IDirectSoundBuffer_GetCurrentPosition(hdsbuf,&play_offset,NULL);
 614         space=buffer_size-(write_offset-play_offset);
 615         if(space > buffer_size)space -= buffer_size; // write_offset < play_offset
 616         if(space < len) len = space;
 617
 618         if (!(flags & AOPLAY_FINAL_CHUNK))
 619         len = (len / ao_data.outburst) * ao_data.outburst;
 620         return write_buffer(data, len);
 621 }
 622
 623 /**
 624 \brief get the delay between the first and last sample in the buffer
 625 \return delay in seconds
 626 */
 627 static float get_delay(void)
 628 {
 629         DWORD play_offset;
 630         int space;
 631         IDirectSoundBuffer_GetCurrentPosition(hdsbuf,&play_offset,NULL);
 632         space=play_offset-write_offset;
 633         if(space <= 0)space += buffer_size;
 634         return (float)(buffer_size - space) / (float)ao_data.bps;
 635 }