fake_audio_output_stream.cc 2.6 KB

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  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. #include "media/audio/fake_audio_output_stream.h"
  5. #include "base/bind.h"
  6. #include "base/callback_helpers.h"
  7. #include "base/check.h"
  8. #include "base/task/single_thread_task_runner.h"
  9. #include "base/time/time.h"
  10. #include "media/audio/audio_manager_base.h"
  11. namespace media {
  12. // static
  13. AudioOutputStream* FakeAudioOutputStream::MakeFakeStream(
  14. AudioManagerBase* manager, const AudioParameters& params) {
  15. return new FakeAudioOutputStream(manager, params);
  16. }
  17. FakeAudioOutputStream::FakeAudioOutputStream(AudioManagerBase* manager,
  18. const AudioParameters& params)
  19. : audio_manager_(manager),
  20. fixed_data_delay_(FakeAudioWorker::ComputeFakeOutputDelay(params)),
  21. callback_(nullptr),
  22. fake_worker_(manager->GetWorkerTaskRunner(), params),
  23. audio_bus_(AudioBus::Create(params)) {}
  24. FakeAudioOutputStream::~FakeAudioOutputStream() {
  25. DCHECK(!callback_);
  26. }
  27. bool FakeAudioOutputStream::Open() {
  28. DCHECK(audio_manager_->GetTaskRunner()->BelongsToCurrentThread());
  29. audio_bus_->Zero();
  30. return true;
  31. }
  32. void FakeAudioOutputStream::Start(AudioSourceCallback* callback) {
  33. DCHECK(audio_manager_->GetTaskRunner()->BelongsToCurrentThread());
  34. callback_ = callback;
  35. fake_worker_.Start(base::BindRepeating(&FakeAudioOutputStream::CallOnMoreData,
  36. base::Unretained(this)));
  37. }
  38. void FakeAudioOutputStream::Stop() {
  39. DCHECK(audio_manager_->GetTaskRunner()->BelongsToCurrentThread());
  40. fake_worker_.Stop();
  41. callback_ = nullptr;
  42. }
  43. void FakeAudioOutputStream::Close() {
  44. DCHECK(!callback_);
  45. DCHECK(audio_manager_->GetTaskRunner()->BelongsToCurrentThread());
  46. audio_manager_->ReleaseOutputStream(this);
  47. }
  48. void FakeAudioOutputStream::Flush() {}
  49. void FakeAudioOutputStream::SetVolume(double volume) {}
  50. void FakeAudioOutputStream::GetVolume(double* volume) {
  51. *volume = 0;
  52. }
  53. void FakeAudioOutputStream::CallOnMoreData(base::TimeTicks ideal_time,
  54. base::TimeTicks now) {
  55. DCHECK(audio_manager_->GetWorkerTaskRunner()->BelongsToCurrentThread());
  56. // Real streams provide small tweaks to their delay values, alongside the
  57. // current system time; and so the same is done here.
  58. const auto delay =
  59. fixed_data_delay_ + std::max(base::TimeDelta(), ideal_time - now);
  60. callback_->OnMoreData(delay, now, 0, audio_bus_.get());
  61. }
  62. void FakeAudioOutputStream::SetMute(bool muted) {}
  63. } // namespace media