modules/access/wasapi.c

   1 /**
   2  * \file wasapi.c
   3  * \brief Windows Audio Session API capture plugin for VLC
   4  */
   5 /*****************************************************************************
   6  * Copyright (C) 2014-2015 Rémi Denis-Courmont
   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 #ifdef HAVE_CONFIG_H
  24 # include "config.h"
  25 #endif
  26
  27 #define INITGUID
  28 #define COBJMACROS
  29 #define CONST_VTABLE
  30
  31 #include <assert.h>
  32 #include <stdlib.h>
  33
  34 #define _DECL_DLLMAIN
  35 #include <vlc_common.h>
  36 #include <vlc_aout.h>
  37 #include <vlc_demux.h>
  38 #include <vlc_plugin.h>
  39 #include <mmdeviceapi.h>
  40 #include <audioclient.h>
  41
  42 static LARGE_INTEGER freq; /* performance counters frequency */
  43
  44 BOOL WINAPI DllMain(HANDLE dll, DWORD reason, LPVOID reserved)
  45 {
  46     (void) dll;
  47     (void) reserved;
  48
  49     switch (reason)
  50     {
  51         case DLL_PROCESS_ATTACH:
  52             if (!QueryPerformanceFrequency(&freq))
  53                 return FALSE;
  54             break;
  55     }
  56     return TRUE;
  57 }
  58
  59 static msftime_t GetQPC(void)
  60 {
  61     LARGE_INTEGER counter;
  62
  63     if (!QueryPerformanceCounter(&counter))
  64         abort();
  65
  66     lldiv_t d = lldiv(counter.QuadPart, freq.QuadPart);
  67     return (d.quot * 10000000) + ((d.rem * 10000000) / freq.QuadPart);
  68 }
  69
  70 static_assert(CLOCK_FREQ * 10 == 10000000,
  71               "REFERENCE_TIME conversion broken");
  72
  73 static EDataFlow GetDeviceFlow(IMMDevice *dev)
  74 {
  75     void *pv;
  76
  77     if (FAILED(IMMDevice_QueryInterface(dev, &IID_IMMEndpoint, &pv)))
  78         return false;
  79
  80     IMMEndpoint *ep = pv;
  81     EDataFlow flow;
  82
  83     if (SUCCEEDED(IMMEndpoint_GetDataFlow(ep, &flow)))
  84         flow = eAll;
  85     IMMEndpoint_Release(ep);
  86     return flow;
  87 }
  88
  89 static IAudioClient *GetClient(demux_t *demux, bool *restrict loopbackp)
  90 {
  91     IMMDeviceEnumerator *e;
  92     IMMDevice *dev;
  93     void *pv;
  94     HRESULT hr;
  95
  96     hr = CoCreateInstance(&CLSID_MMDeviceEnumerator, NULL, CLSCTX_ALL,
  97                           &IID_IMMDeviceEnumerator, &pv);
  98     if (FAILED(hr))
  99     {
 100         msg_Err(demux, "cannot create device enumerator (error 0x%lX)", hr);
 101         return NULL;
 102     }
 103     e = pv;
 104
 105     bool loopback = var_InheritBool(demux, "wasapi-loopback");
 106     EDataFlow flow = loopback ? eRender : eCapture;
 107     ERole role = loopback ? eConsole : eCommunications;
 108
 109     hr = IMMDeviceEnumerator_GetDefaultAudioEndpoint(e, flow, role, &dev);
 110     IMMDeviceEnumerator_Release(e);
 111     if (FAILED(hr))
 112     {
 113         msg_Err(demux, "cannot get default device (error 0x%lX)", hr);
 114         return NULL;
 115     }
 116
 117     hr = IMMDevice_Activate(dev, &IID_IAudioClient, CLSCTX_ALL, NULL, &pv);
 118     *loopbackp = GetDeviceFlow(dev) == eRender;
 119     IMMDevice_Release(dev);
 120     if (FAILED(hr))
 121         msg_Err(demux, "cannot activate device (error 0x%lX)", hr);
 122     return pv;
 123 }
 124
 125 static int vlc_FromWave(const WAVEFORMATEX *restrict wf,
 126                         audio_sample_format_t *restrict fmt)
 127 {
 128     fmt->i_rate = wf->nSamplesPerSec;
 129
 130     /* As per MSDN, IAudioClient::GetMixFormat() always uses this format. */
 131     assert(wf->wFormatTag == WAVE_FORMAT_EXTENSIBLE);
 132
 133     const WAVEFORMATEXTENSIBLE *wfe = (void *)wf;
 134
 135     fmt->i_physical_channels = 0;
 136     if (wfe->dwChannelMask & SPEAKER_FRONT_LEFT)
 137         fmt->i_physical_channels |= AOUT_CHAN_LEFT;
 138     if (wfe->dwChannelMask & SPEAKER_FRONT_RIGHT)
 139         fmt->i_physical_channels |= AOUT_CHAN_RIGHT;
 140     if (wfe->dwChannelMask & SPEAKER_FRONT_CENTER)
 141         fmt->i_physical_channels |= AOUT_CHAN_CENTER;
 142     if (wfe->dwChannelMask & SPEAKER_LOW_FREQUENCY)
 143         fmt->i_physical_channels |= AOUT_CHAN_LFE;
 144
 145     assert(vlc_popcount(wfe->dwChannelMask) == wf->nChannels);
 146
 147     if (IsEqualIID(&wfe->SubFormat, &KSDATAFORMAT_SUBTYPE_PCM))
 148     {
 149         switch (wf->wBitsPerSample)
 150         {
 151             case 32:
 152                 switch (wfe->Samples.wValidBitsPerSample)
 153                 {
 154                     case 32:
 155                         fmt->i_format = VLC_CODEC_S32N;
 156                         break;
 157                     case 24:
 158 #ifdef WORDS_BIGENDIAN
 159                         fmt->i_format = VLC_CODEC_S24B32;
 160 #else
 161                         fmt->i_format = VLC_CODEC_S24L32;
 162 #endif
 163                         break;
 164                     default:
 165                         return -1;
 166                 }
 167                 break;
 168             case 24:
 169                 if (wfe->Samples.wValidBitsPerSample == 24)
 170                     fmt->i_format = VLC_CODEC_S24N;
 171                 else
 172                     return -1;
 173                 break;
 174             case 16:
 175                 if (wfe->Samples.wValidBitsPerSample == 16)
 176                     fmt->i_format = VLC_CODEC_S16N;
 177                 else
 178                     return -1;
 179                 break;
 180             case 8:
 181                 if (wfe->Samples.wValidBitsPerSample == 8)
 182                     fmt->i_format = VLC_CODEC_S8;
 183                 else
 184                     return -1;
 185                 break;
 186             default:
 187                 return -1;
 188         }
 189     }
 190     else if (IsEqualIID(&wfe->SubFormat, &KSDATAFORMAT_SUBTYPE_IEEE_FLOAT))
 191     {
 192         if (wf->wBitsPerSample != wfe->Samples.wValidBitsPerSample)
 193             return -1;
 194
 195         switch (wf->wBitsPerSample)
 196         {
 197             case 64:
 198                 fmt->i_format = VLC_CODEC_FL64;
 199                 break;
 200             case 32:
 201                 fmt->i_format = VLC_CODEC_FL32;
 202                 break;
 203             default:
 204                 return -1;
 205         }
 206     }
 207     /*else if (IsEqualIID(&wfe->Subformat, &KSDATAFORMAT_SUBTYPE_DRM)) {} */
 208     else if (IsEqualIID(&wfe->SubFormat, &KSDATAFORMAT_SUBTYPE_ALAW))
 209         fmt->i_format = VLC_CODEC_ALAW;
 210     else if (IsEqualIID(&wfe->SubFormat, &KSDATAFORMAT_SUBTYPE_MULAW))
 211         fmt->i_format = VLC_CODEC_MULAW;
 212     else if (IsEqualIID(&wfe->SubFormat, &KSDATAFORMAT_SUBTYPE_ADPCM))
 213         fmt->i_format = VLC_CODEC_ADPCM_MS;
 214     else
 215         return -1;
 216
 217     aout_FormatPrepare(fmt);
 218     if (wf->nChannels != fmt->i_channels)
 219         return -1;
 220
 221     return 0;
 222 }
 223
 224 static es_out_id_t *CreateES(demux_t *demux, IAudioClient *client, bool loop,
 225                              vlc_tick_t caching, size_t *restrict frame_size)
 226 {
 227     es_format_t fmt;
 228     WAVEFORMATEX *pwf;
 229     HRESULT hr;
 230
 231     hr = IAudioClient_GetMixFormat(client, &pwf);
 232     if (FAILED(hr))
 233     {
 234         msg_Err(demux, "cannot get mix format (error 0x%lX)", hr);
 235         return NULL;
 236     }
 237
 238     es_format_Init(&fmt, AUDIO_ES, 0);
 239     if (vlc_FromWave(pwf, &fmt.audio))
 240     {
 241         msg_Err(demux, "unsupported mix format");
 242         CoTaskMemFree(pwf);
 243         return NULL;
 244     }
 245
 246     fmt.i_codec = fmt.audio.i_format;
 247     fmt.i_bitrate = fmt.audio.i_bitspersample * fmt.audio.i_channels
 248                                               * fmt.audio.i_rate;
 249     *frame_size = fmt.audio.i_bitspersample * fmt.audio.i_channels / 8;
 250
 251     DWORD flags = AUDCLNT_STREAMFLAGS_EVENTCALLBACK;
 252     if (loop)
 253         flags |= AUDCLNT_STREAMFLAGS_LOOPBACK;
 254
 255     /* Request at least thrice the PTS delay */
 256     REFERENCE_TIME bufsize = MSFTIME_FROM_VLC_TICK( caching ) * 3;
 257
 258     hr = IAudioClient_Initialize(client, AUDCLNT_SHAREMODE_SHARED, flags,
 259                                  bufsize, 0, pwf, NULL);
 260     CoTaskMemFree(pwf);
 261     if (FAILED(hr))
 262     {
 263         msg_Err(demux, "cannot initialize audio client (error 0x%lX)", hr);
 264         return NULL;
 265     }
 266     return es_out_Add(demux->out, &fmt);
 267 }
 268
 269 typedef struct
 270 {
 271     IAudioClient *client;
 272     es_out_id_t *es;
 273
 274     size_t frame_size;
 275     vlc_tick_t caching;
 276     vlc_tick_t start_time;
 277
 278     HANDLE events[2];
 279     union {
 280         HANDLE thread;
 281         HANDLE ready;
 282     };
 283 } demux_sys_t;
 284
 285 static unsigned __stdcall Thread(void *data)
 286 {
 287     demux_t *demux = data;
 288     demux_sys_t *sys = demux->p_sys;
 289     IAudioCaptureClient *capture = NULL;
 290     void *pv;
 291     HRESULT hr;
 292
 293     hr = CoInitializeEx(NULL, COINIT_MULTITHREADED);
 294     assert(SUCCEEDED(hr)); /* COM already allocated by parent thread */
 295     SetEvent(sys->ready);
 296
 297     hr = IAudioClient_GetService(sys->client, &IID_IAudioCaptureClient, &pv);
 298     if (FAILED(hr))
 299     {
 300         msg_Err(demux, "cannot get capture client (error 0x%lX)", hr);
 301         goto out;
 302     }
 303     capture = pv;
 304
 305     hr = IAudioClient_Start(sys->client);
 306     if (FAILED(hr))
 307     {
 308         msg_Err(demux, "cannot start client (error 0x%lX)", hr);
 309         IAudioCaptureClient_Release(capture);
 310         goto out;
 311     }
 312
 313     while (WaitForMultipleObjects(2, sys->events, FALSE, INFINITE)
 314             != WAIT_OBJECT_0)
 315     {
 316         BYTE *buf;
 317         UINT32 frames;
 318         DWORD flags;
 319         UINT64 qpc;
 320         vlc_tick_t pts;
 321
 322         hr = IAudioCaptureClient_GetBuffer(capture, &buf, &frames, &flags,
 323                                            NULL, &qpc);
 324         if (hr != S_OK)
 325             continue;
 326
 327         pts = vlc_tick_now() - VLC_TICK_FROM_MSFTIME(GetQPC() - qpc);
 328
 329         es_out_SetPCR(demux->out, pts);
 330
 331         size_t bytes = frames * sys->frame_size;
 332         block_t *block = block_Alloc(bytes);
 333
 334         if (likely(block != NULL)) {
 335             memcpy(block->p_buffer, buf, bytes);
 336             block->i_nb_samples = frames;
 337             block->i_pts = block->i_dts = pts;
 338             es_out_Send(demux->out, sys->es, block);
 339         }
 340
 341         IAudioCaptureClient_ReleaseBuffer(capture, frames);
 342     }
 343
 344     IAudioClient_Stop(sys->client);
 345     IAudioCaptureClient_Release(capture);
 346 out:
 347     CoUninitialize();
 348     return 0;
 349 }
 350
 351 static int Control(demux_t *demux, int query, va_list ap)
 352 {
 353     demux_sys_t *sys = demux->p_sys;
 354
 355     switch (query)
 356     {
 357         case DEMUX_GET_TIME:
 358             *(va_arg(ap, vlc_tick_t *)) = vlc_tick_now() - sys->start_time;
 359             break;
 360
 361         case DEMUX_GET_PTS_DELAY:
 362             *(va_arg(ap, vlc_tick_t *)) = sys->caching;
 363             break;
 364
 365         case DEMUX_HAS_UNSUPPORTED_META:
 366         case DEMUX_CAN_RECORD:
 367         case DEMUX_CAN_PAUSE:
 368         case DEMUX_CAN_CONTROL_PACE:
 369         case DEMUX_CAN_CONTROL_RATE:
 370         case DEMUX_CAN_SEEK:
 371             *(va_arg(ap, bool *)) = false;
 372             break;
 373
 374         default:
 375             return VLC_EGENERIC;
 376     }
 377
 378     return VLC_SUCCESS;
 379 }
 380
 381 static int Open(vlc_object_t *obj)
 382 {
 383     demux_t *demux = (demux_t *)obj;
 384     HRESULT hr;
 385
 386     if (demux->out == NULL)
 387         return VLC_EGENERIC;
 388
 389     if (demux->psz_location != NULL && *demux->psz_location != '\0')
 390         return VLC_EGENERIC; /* TODO non-default device */
 391
 392     demux_sys_t *sys = vlc_obj_malloc(obj, sizeof (*sys));
 393     if (unlikely(sys == NULL))
 394         return VLC_ENOMEM;
 395
 396     sys->client = NULL;
 397     sys->es = NULL;
 398     sys->caching = VLC_TICK_FROM_MS( var_InheritInteger(obj, "live-caching") );
 399     sys->start_time = vlc_tick_now();
 400     for (unsigned i = 0; i < 2; i++)
 401         sys->events[i] = NULL;
 402
 403     for (unsigned i = 0; i < 2; i++) {
 404         sys->events[i] = CreateEvent(NULL, FALSE, FALSE, NULL);
 405         if (sys->events[i] == NULL)
 406             goto error;
 407     }
 408
 409     hr = CoInitializeEx(NULL, COINIT_MULTITHREADED);
 410     if (unlikely(FAILED(hr))) {
 411         msg_Err(demux, "cannot initialize COM (error 0x%lX)", hr);
 412         goto error;
 413     }
 414
 415     bool loopback;
 416     sys->client = GetClient(demux, &loopback);
 417     if (sys->client == NULL) {
 418         CoUninitialize();
 419         goto error;
 420     }
 421
 422     sys->es = CreateES(demux, sys->client, loopback, sys->caching,
 423                        &sys->frame_size);
 424     if (sys->es == NULL)
 425         goto error;
 426
 427     hr = IAudioClient_SetEventHandle(sys->client, sys->events[1]);
 428     if (FAILED(hr)) {
 429         msg_Err(demux, "cannot set event handle (error 0x%lX)", hr);
 430         goto error;
 431     }
 432
 433     demux->p_sys = sys;
 434
 435     sys->ready = CreateEvent(NULL, FALSE, FALSE, NULL);
 436     if (sys->ready == NULL)
 437         goto error;
 438
 439     uintptr_t h = _beginthreadex(NULL, 0, Thread, demux, 0, NULL);
 440     if (h != 0)
 441         WaitForSingleObject(sys->ready, INFINITE);
 442     CloseHandle(sys->ready);
 443
 444     sys->thread = (HANDLE)h;
 445     if (sys->thread == NULL)
 446         goto error;
 447     CoUninitialize();
 448
 449     demux->pf_demux = NULL;
 450     demux->pf_control = Control;
 451     return VLC_SUCCESS;
 452
 453 error:
 454     if (sys->es != NULL)
 455         es_out_Del(demux->out, sys->es);
 456     if (sys->client != NULL)
 457     {
 458         IAudioClient_Release(sys->client);
 459         CoUninitialize();
 460     }
 461     for (unsigned i = 0; i < 2; i++)
 462         if (sys->events[i] != NULL)
 463             CloseHandle(sys->events[i]);
 464     return VLC_ENOMEM;
 465 }
 466
 467 static void Close (vlc_object_t *obj)
 468 {
 469     demux_t *demux = (demux_t *)obj;
 470     demux_sys_t *sys = demux->p_sys;
 471     HRESULT hr;
 472
 473     hr = CoInitializeEx(NULL, COINIT_MULTITHREADED);
 474     assert(SUCCEEDED(hr));
 475
 476     SetEvent(sys->events[0]);
 477     WaitForSingleObject(sys->thread, INFINITE);
 478     CloseHandle(sys->thread);
 479
 480     es_out_Del(demux->out, sys->es);
 481     IAudioClient_Release(sys->client);
 482     CoUninitialize();
 483     for (unsigned i = 0; i < 2; i++)
 484         CloseHandle(sys->events[i]);
 485 }
 486
 487 #define LOOPBACK_TEXT N_("Loopback mode")
 488 #define LOOPBACK_LONGTEXT N_("Record an audio rendering endpoint.")
 489
 490 vlc_module_begin()
 491     set_shortname(N_("WASAPI"))
 492     set_description(N_("Windows Audio Session API input"))
 493     set_capability("access", 0)
 494     set_category(CAT_INPUT)
 495     set_subcategory(SUBCAT_INPUT_ACCESS)
 496
 497     add_bool("wasapi-loopback", false, LOOPBACK_TEXT, LOOPBACK_LONGTEXT, true)
 498
 499     add_shortcut("wasapi")
 500     set_callbacks(Open, Close)
 501 vlc_module_end()