media/audio/win/wavein_input_win.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/audio/win/wavein_input_win.h"
   6
   7 #pragma comment(lib, "winmm.lib")
   8
   9 #include "base/logging.h"
  10 #include "media/audio/audio_io.h"
  11 #include "media/audio/audio_util.h"
  12 #include "media/audio/win/audio_manager_win.h"
  13 #include "media/audio/win/device_enumeration_win.h"
  14
  15 namespace media {
  16
  17 // Our sound buffers are allocated once and kept in a linked list using the
  18 // the WAVEHDR::dwUser variable. The last buffer points to the first buffer.
  19 static WAVEHDR* GetNextBuffer(WAVEHDR* current) {
  20   return reinterpret_cast<WAVEHDR*>(current->dwUser);
  21 }
  22
  23 PCMWaveInAudioInputStream::PCMWaveInAudioInputStream(
  24     AudioManagerWin* manager, const AudioParameters& params, int num_buffers,
  25     const std::string& device_id)
  26     : state_(kStateEmpty),
  27       manager_(manager),
  28       device_id_(device_id),
  29       wavein_(NULL),
  30       callback_(NULL),
  31       num_buffers_(num_buffers),
  32       buffer_(NULL),
  33       channels_(params.channels()) {
  34   DCHECK_GT(num_buffers_, 0);
  35   format_.wFormatTag = WAVE_FORMAT_PCM;
  36   format_.nChannels = params.channels() > 2 ? 2 : params.channels();
  37   format_.nSamplesPerSec = params.sample_rate();
  38   format_.wBitsPerSample = params.bits_per_sample();
  39   format_.cbSize = 0;
  40   format_.nBlockAlign = (format_.nChannels * format_.wBitsPerSample) / 8;
  41   format_.nAvgBytesPerSec = format_.nBlockAlign * format_.nSamplesPerSec;
  42   buffer_size_ = params.frames_per_buffer() * format_.nBlockAlign;
  43   // If we don't have a packet size we use 100ms.
  44   if (!buffer_size_)
  45     buffer_size_ = format_.nAvgBytesPerSec / 10;
  46   // The event is auto-reset.
  47   stopped_event_.Set(::CreateEventW(NULL, FALSE, FALSE, NULL));
  48 }
  49
  50 PCMWaveInAudioInputStream::~PCMWaveInAudioInputStream() {
  51   DCHECK(NULL == wavein_);
  52 }
  53
  54 bool PCMWaveInAudioInputStream::Open() {
  55   DCHECK(thread_checker_.CalledOnValidThread());
  56   if (state_ != kStateEmpty)
  57     return false;
  58   if (num_buffers_ < 2 || num_buffers_ > 10)
  59     return false;
  60
  61   // Convert the stored device id string into an unsigned integer
  62   // corresponding to the selected device.
  63   UINT device_id = WAVE_MAPPER;
  64   if (!GetDeviceId(&device_id)) {
  65     return false;
  66   }
  67
  68   // Open the specified input device for recording.
  69   MMRESULT result = MMSYSERR_NOERROR;
  70   result = ::waveInOpen(&wavein_, device_id, &format_,
  71                         reinterpret_cast<DWORD_PTR>(WaveCallback),
  72                         reinterpret_cast<DWORD_PTR>(this),
  73                         CALLBACK_FUNCTION);
  74   if (result != MMSYSERR_NOERROR)
  75     return false;
  76
  77   SetupBuffers();
  78   state_ = kStateReady;
  79   return true;
  80 }
  81
  82 void PCMWaveInAudioInputStream::SetupBuffers() {
  83   WAVEHDR* last = NULL;
  84   WAVEHDR* first = NULL;
  85   for (int ix = 0; ix != num_buffers_; ++ix) {
  86     uint32 sz = sizeof(WAVEHDR) + buffer_size_;
  87     buffer_ =  reinterpret_cast<WAVEHDR*>(new char[sz]);
  88     buffer_->lpData = reinterpret_cast<char*>(buffer_) + sizeof(WAVEHDR);
  89     buffer_->dwBufferLength = buffer_size_;
  90     buffer_->dwBytesRecorded = 0;
  91     buffer_->dwUser = reinterpret_cast<DWORD_PTR>(last);
  92     buffer_->dwFlags = WHDR_DONE;
  93     buffer_->dwLoops = 0;
  94     if (ix == 0)
  95       first = buffer_;
  96     last = buffer_;
  97     ::waveInPrepareHeader(wavein_, buffer_, sizeof(WAVEHDR));
  98   }
  99   // Fix the first buffer to point to the last one.
 100   first->dwUser = reinterpret_cast<DWORD_PTR>(last);
 101 }
 102
 103 void PCMWaveInAudioInputStream::FreeBuffers() {
 104   WAVEHDR* current = buffer_;
 105   for (int ix = 0; ix != num_buffers_; ++ix) {
 106     WAVEHDR* next = GetNextBuffer(current);
 107     if (current->dwFlags & WHDR_PREPARED)
 108       ::waveInUnprepareHeader(wavein_, current, sizeof(WAVEHDR));
 109     delete[] reinterpret_cast<char*>(current);
 110     current = next;
 111   }
 112   buffer_ = NULL;
 113 }
 114
 115 void PCMWaveInAudioInputStream::Start(AudioInputCallback* callback) {
 116   DCHECK(thread_checker_.CalledOnValidThread());
 117   if (state_ != kStateReady)
 118     return;
 119
 120   DCHECK(!callback_);
 121   callback_ = callback;
 122   state_ = kStateRecording;
 123
 124   WAVEHDR* buffer = buffer_;
 125   for (int ix = 0; ix != num_buffers_; ++ix) {
 126     QueueNextPacket(buffer);
 127     buffer = GetNextBuffer(buffer);
 128   }
 129   buffer = buffer_;
 130
 131   MMRESULT result = ::waveInStart(wavein_);
 132   if (result != MMSYSERR_NOERROR) {
 133     HandleError(result);
 134     state_ = kStateReady;
 135     callback_ = NULL;
 136   }
 137 }
 138
 139 // Stopping is tricky. First, no buffer should be locked by the audio driver
 140 // or else the waveInReset() will deadlock and secondly, the callback should
 141 // not be inside the AudioInputCallback's OnData because waveInReset()
 142 // forcefully kills the callback thread.
 143 void PCMWaveInAudioInputStream::Stop() {
 144   DVLOG(1) << "PCMWaveInAudioInputStream::Stop()";
 145   DCHECK(thread_checker_.CalledOnValidThread());
 146   if (state_ != kStateRecording)
 147     return;
 148
 149   bool already_stopped = false;
 150   {
 151     // Tell the callback that we're stopping.
 152     // As a result, |stopped_event_| will be signaled in callback method.
 153     base::AutoLock auto_lock(lock_);
 154     already_stopped = (callback_ == NULL);
 155     callback_ = NULL;
 156   }
 157
 158   if (already_stopped)
 159     return;
 160
 161   // Wait for the callback to finish, it will signal us when ready to be reset.
 162   DWORD wait = ::WaitForSingleObject(stopped_event_, INFINITE);
 163   DCHECK_EQ(wait, WAIT_OBJECT_0);
 164
 165   // Stop input and reset the current position to zero for |wavein_|.
 166   // All pending buffers are marked as done and returned to the application.
 167   MMRESULT res = ::waveInReset(wavein_);
 168   DCHECK_EQ(res, static_cast<MMRESULT>(MMSYSERR_NOERROR));
 169
 170   state_ = kStateReady;
 171 }
 172
 173 void PCMWaveInAudioInputStream::Close() {
 174   DVLOG(1) << "PCMWaveInAudioInputStream::Close()";
 175   DCHECK(thread_checker_.CalledOnValidThread());
 176
 177   // We should not call Close() while recording. Catch it with DCHECK and
 178   // implement auto-stop just in case.
 179   DCHECK_NE(state_, kStateRecording);
 180   Stop();
 181
 182   if (wavein_) {
 183     FreeBuffers();
 184
 185     // waveInClose() generates a WIM_CLOSE callback.  In case Start() was never
 186     // called, force a reset to ensure close succeeds.
 187     MMRESULT res = ::waveInReset(wavein_);
 188     DCHECK_EQ(res, static_cast<MMRESULT>(MMSYSERR_NOERROR));
 189     res = ::waveInClose(wavein_);
 190     DCHECK_EQ(res, static_cast<MMRESULT>(MMSYSERR_NOERROR));
 191     state_ = kStateClosed;
 192     wavein_ = NULL;
 193   }
 194
 195   // Tell the audio manager that we have been released. This can result in
 196   // the manager destroying us in-place so this needs to be the last thing
 197   // we do on this function.
 198   manager_->ReleaseInputStream(this);
 199 }
 200
 201 double PCMWaveInAudioInputStream::GetMaxVolume() {
 202   // TODO(henrika): Add volume support using the Audio Mixer API.
 203   return 0.0;
 204 }
 205
 206 void PCMWaveInAudioInputStream::SetVolume(double volume) {
 207   // TODO(henrika): Add volume support using the Audio Mixer API.
 208 }
 209
 210 double PCMWaveInAudioInputStream::GetVolume() {
 211   // TODO(henrika): Add volume support using the Audio Mixer API.
 212   return 0.0;
 213 }
 214
 215 void PCMWaveInAudioInputStream::SetAutomaticGainControl(bool enabled) {
 216   // TODO(henrika): Add AGC support when volume control has been added.
 217   NOTIMPLEMENTED();
 218 }
 219
 220 bool PCMWaveInAudioInputStream::GetAutomaticGainControl() {
 221   // TODO(henrika): Add AGC support when volume control has been added.
 222   NOTIMPLEMENTED();
 223   return false;
 224 }
 225
 226 void PCMWaveInAudioInputStream::HandleError(MMRESULT error) {
 227   DLOG(WARNING) << "PCMWaveInAudio error " << error;
 228   callback_->OnError(this);
 229 }
 230
 231 void PCMWaveInAudioInputStream::QueueNextPacket(WAVEHDR *buffer) {
 232   MMRESULT res = ::waveInAddBuffer(wavein_, buffer, sizeof(WAVEHDR));
 233   if (res != MMSYSERR_NOERROR)
 234     HandleError(res);
 235 }
 236
 237 bool PCMWaveInAudioInputStream::GetDeviceId(UINT* device_index) {
 238   // Deliver the default input device id (WAVE_MAPPER) if the default
 239   // device has been selected.
 240   if (device_id_ == AudioManagerBase::kDefaultDeviceId) {
 241     *device_index = WAVE_MAPPER;
 242     return true;
 243   }
 244
 245   // Get list of all available and active devices.
 246   AudioDeviceNames device_names;
 247   if (!media::GetInputDeviceNamesWinXP(&device_names))
 248     return false;
 249
 250   if (device_names.empty())
 251     return false;
 252
 253   // Search the full list of devices and compare with the specified
 254   // device id which was specified in the constructor. Stop comparing
 255   // when a match is found and return the corresponding index.
 256   UINT index = 0;
 257   bool found_device = false;
 258   AudioDeviceNames::const_iterator it = device_names.begin();
 259   while (it != device_names.end()) {
 260     if (it->unique_id.compare(device_id_) == 0) {
 261       *device_index = index;
 262       found_device = true;
 263       break;
 264     }
 265     ++index;
 266     ++it;
 267   }
 268
 269   return found_device;
 270 }
 271
 272 // Windows calls us back in this function when some events happen. Most notably
 273 // when it has an audio buffer with recorded data.
 274 void PCMWaveInAudioInputStream::WaveCallback(HWAVEIN hwi, UINT msg,
 275                                              DWORD_PTR instance,
 276                                              DWORD_PTR param1, DWORD_PTR) {
 277   PCMWaveInAudioInputStream* obj =
 278       reinterpret_cast<PCMWaveInAudioInputStream*>(instance);
 279
 280   // The lock ensures that Stop() can't be called during a callback.
 281   base::AutoLock auto_lock(obj->lock_);
 282
 283   if (msg == WIM_DATA) {
 284     // The WIM_DATA message is sent when waveform-audio data is present in
 285     // the input buffer and the buffer is being returned to the application.
 286     // The message can be sent when the buffer is full or after the
 287     // waveInReset function is called.
 288     if (obj->callback_) {
 289       // TODO(henrika): the |volume| parameter is always set to zero since
 290       // there is currently no support for controlling the microphone volume
 291       // level.
 292       WAVEHDR* buffer = reinterpret_cast<WAVEHDR*>(param1);
 293       obj->callback_->OnData(obj,
 294                              reinterpret_cast<const uint8*>(buffer->lpData),
 295                              buffer->dwBytesRecorded,
 296                              buffer->dwBytesRecorded,
 297                              0.0);
 298
 299       // Queue the finished buffer back with the audio driver. Since we are
 300       // reusing the same buffers we can get away without calling
 301       // waveInPrepareHeader.
 302       obj->QueueNextPacket(buffer);
 303     } else {
 304       // Main thread has called Stop() and set |callback_| to NULL and is
 305       // now waiting to issue waveInReset which will kill this thread.
 306       // We should not call AudioSourceCallback code anymore.
 307       ::SetEvent(obj->stopped_event_);
 308     }
 309   } else if (msg == WIM_CLOSE) {
 310     // Intentionaly no-op for now.
 311   } else if (msg == WIM_OPEN) {
 312     // Intentionaly no-op for now.
 313   }
 314 }
 315
 316 }  // namespace media