MuteSource Audio During Full Screen Cast

media/audio/win/audio_low_latency_input_win.h

Index: media/audio/win/audio_low_latency_input_win.h
diff --git a/media/audio/win/audio_low_latency_input_win.h b/media/audio/win/audio_low_latency_input_win.h
index 2f718f91523b09cbbfe1ed58c7440825e16606e9..633531df278ee4e450b378bc4d58f363c59f1e88 100644
--- a/media/audio/win/audio_low_latency_input_win.h
+++ b/media/audio/win/audio_low_latency_input_win.h
@@ -1,215 +1,226 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-//
-// Implementation of AudioInputStream for Windows using Windows Core Audio
-// WASAPI for low latency capturing.
-//
-// Overview of operation:
-//
-// - An object of WASAPIAudioInputStream is created by the AudioManager
-//   factory.
-// - Next some thread will call Open(), at that point the underlying
-//   Core Audio APIs are utilized to create two WASAPI interfaces called
-//   IAudioClient and IAudioCaptureClient.
-// - Then some thread will call Start(sink).
-//   A thread called "wasapi_capture_thread" is started and this thread listens
-//   on an event signal which is set periodically by the audio engine for
-//   each recorded data packet. As a result, data samples will be provided
-//   to the registered sink.
-// - At some point, a thread will call Stop(), which stops and joins the
-//   capture thread and at the same time stops audio streaming.
-// - The same thread that called stop will call Close() where we cleanup
-//   and notify the audio manager, which likely will destroy this object.
-//
-// Implementation notes:
-//
-// - The minimum supported client is Windows Vista.
-// - This implementation is single-threaded, hence:
-//    o Construction and destruction must take place from the same thread.
-//    o It is recommended to call all APIs from the same thread as well.
-// - It is recommended to first acquire the native sample rate of the default
-//   input device and then use the same rate when creating this object. Use
-//   WASAPIAudioInputStream::HardwareSampleRate() to retrieve the sample rate.
-// - Calling Close() also leads to self destruction.
-//
-// Core Audio API details:
-//
-// - Utilized MMDevice interfaces:
-//     o IMMDeviceEnumerator
-//     o IMMDevice
-// - Utilized WASAPI interfaces:
-//     o IAudioClient
-//     o IAudioCaptureClient
-// - The stream is initialized in shared mode and the processing of the
-//   audio buffer is event driven.
-// - The Multimedia Class Scheduler service (MMCSS) is utilized to boost
-//   the priority of the capture thread.
-// - Audio applications that use the MMDevice API and WASAPI typically use
-//   the ISimpleAudioVolume interface to manage stream volume levels on a
-//   per-session basis. It is also possible to use of the IAudioEndpointVolume
-//   interface to control the master volume level of an audio endpoint device.
-//   This implementation is using the ISimpleAudioVolume interface.
-//   MSDN states that "In rare cases, a specialized audio application might
-//   require the use of the IAudioEndpointVolume".
-//
-#ifndef MEDIA_AUDIO_WIN_AUDIO_LOW_LATENCY_INPUT_WIN_H_
-#define MEDIA_AUDIO_WIN_AUDIO_LOW_LATENCY_INPUT_WIN_H_
-
-#include <Audioclient.h>
-#include <MMDeviceAPI.h>
-#include <stddef.h>
-#include <stdint.h>
-
-#include <memory>
-#include <string>
-
-#include "base/compiler_specific.h"
-#include "base/macros.h"
-#include "base/threading/non_thread_safe.h"
-#include "base/threading/platform_thread.h"
-#include "base/threading/simple_thread.h"
-#include "base/win/scoped_co_mem.h"
-#include "base/win/scoped_com_initializer.h"
-#include "base/win/scoped_comptr.h"
-#include "base/win/scoped_handle.h"
-#include "media/audio/agc_audio_stream.h"
-#include "media/base/audio_parameters.h"
-#include "media/base/media_export.h"
-
-namespace media {
-
-class AudioBus;
-class AudioManagerWin;
-
-// AudioInputStream implementation using Windows Core Audio APIs.
-class MEDIA_EXPORT WASAPIAudioInputStream
-    : public AgcAudioStream<AudioInputStream>,
-      public base::DelegateSimpleThread::Delegate,
-      NON_EXPORTED_BASE(public base::NonThreadSafe) {
- public:
-  // The ctor takes all the usual parameters, plus |manager| which is the
-  // the audio manager who is creating this object.
-  WASAPIAudioInputStream(AudioManagerWin* manager,
-                         const AudioParameters& params,
-                         const std::string& device_id);
-
-  // The dtor is typically called by the AudioManager only and it is usually
-  // triggered by calling AudioInputStream::Close().
-  ~WASAPIAudioInputStream() override;
-
-  // Implementation of AudioInputStream.
-  bool Open() override;
-  void Start(AudioInputCallback* callback) override;
-  void Stop() override;
-  void Close() override;
-  double GetMaxVolume() override;
-  void SetVolume(double volume) override;
-  double GetVolume() override;
-  bool IsMuted() override;
-
-  bool started() const { return started_; }
-
- private:
-  // DelegateSimpleThread::Delegate implementation.
-  void Run() override;
-
-  // Issues the OnError() callback to the |sink_|.
-  void HandleError(HRESULT err);
-
-  // The Open() method is divided into these sub methods.
-  HRESULT SetCaptureDevice();
-  HRESULT ActivateCaptureDevice();
-  HRESULT GetAudioEngineStreamFormat();
-  bool DesiredFormatIsSupported();
-  HRESULT InitializeAudioEngine();
-
-  // Our creator, the audio manager needs to be notified when we close.
-  AudioManagerWin* manager_;
-
-  // Capturing is driven by this thread (which has no message loop).
-  // All OnData() callbacks will be called from this thread.
-  base::DelegateSimpleThread* capture_thread_;
-
-  // Contains the desired audio format which is set up at construction.
-  WAVEFORMATEX format_;
-
-  bool opened_;
-  bool started_;
-
-  // Size in bytes of each audio frame (4 bytes for 16-bit stereo PCM)
-  size_t frame_size_;
-
-  // Size in audio frames of each audio packet where an audio packet
-  // is defined as the block of data which the user received in each
-  // OnData() callback.
-  size_t packet_size_frames_;
-
-  // Size in bytes of each audio packet.
-  size_t packet_size_bytes_;
-
-  // Length of the audio endpoint buffer.
-  uint32_t endpoint_buffer_size_frames_;
-
-  // Contains the unique name of the selected endpoint device.
-  // Note that AudioDeviceDescription::kDefaultDeviceId represents the default
-  // device role and is not a valid ID as such.
-  std::string device_id_;
-
-  // Conversion factor used in delay-estimation calculations.
-  // Converts a raw performance counter value to 100-nanosecond unit.
-  double perf_count_to_100ns_units_;
-
-  // Conversion factor used in delay-estimation calculations.
-  // Converts from milliseconds to audio frames.
-  double ms_to_frame_count_;
-
-  // Pointer to the object that will receive the recorded audio samples.
-  AudioInputCallback* sink_;
-
-  // Windows Multimedia Device (MMDevice) API interfaces.
-
-  // An IMMDevice interface which represents an audio endpoint device.
-  base::win::ScopedComPtr<IMMDevice> endpoint_device_;
-
-  // Windows Audio Session API (WASAPI) interfaces.
-
-  // An IAudioClient interface which enables a client to create and initialize
-  // an audio stream between an audio application and the audio engine.
-  base::win::ScopedComPtr<IAudioClient> audio_client_;
-
-  // Loopback IAudioClient doesn't support event-driven mode, so a separate
-  // IAudioClient is needed to receive notifications when data is available in
-  // the buffer. For loopback input |audio_client_| is used to receive data,
-  // while |audio_render_client_for_loopback_| is used to get notifications
-  // when a new buffer is ready. See comment in InitializeAudioEngine() for
-  // details.
-  base::win::ScopedComPtr<IAudioClient> audio_render_client_for_loopback_;
-
-  // The IAudioCaptureClient interface enables a client to read input data
-  // from a capture endpoint buffer.
-  base::win::ScopedComPtr<IAudioCaptureClient> audio_capture_client_;
-
-  // The ISimpleAudioVolume interface enables a client to control the
-  // master volume level of an audio session.
-  // The volume-level is a value in the range 0.0 to 1.0.
-  // This interface does only work with shared-mode streams.
-  base::win::ScopedComPtr<ISimpleAudioVolume> simple_audio_volume_;
-
-  // The audio engine will signal this event each time a buffer has been
-  // recorded.
-  base::win::ScopedHandle audio_samples_ready_event_;
-
-  // This event will be signaled when capturing shall stop.
-  base::win::ScopedHandle stop_capture_event_;
-
-  // Extra audio bus used for storage of deinterleaved data for the OnData
-  // callback.
-  std::unique_ptr<media::AudioBus> audio_bus_;
-
-  DISALLOW_COPY_AND_ASSIGN(WASAPIAudioInputStream);
-};
-
-}  // namespace media
-
-#endif  // MEDIA_AUDIO_WIN_AUDIO_LOW_LATENCY_INPUT_WIN_H_
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Implementation of AudioInputStream for Windows using Windows Core Audio
+// WASAPI for low latency capturing.
+//
+// Overview of operation:
+//
+// - An object of WASAPIAudioInputStream is created by the AudioManager
+//   factory.
+// - Next some thread will call Open(), at that point the underlying
+//   Core Audio APIs are utilized to create two WASAPI interfaces called
+//   IAudioClient and IAudioCaptureClient.
+// - Then some thread will call Start(sink).
+//   A thread called "wasapi_capture_thread" is started and this thread listens
+//   on an event signal which is set periodically by the audio engine for
+//   each recorded data packet. As a result, data samples will be provided
+//   to the registered sink.
+// - At some point, a thread will call Stop(), which stops and joins the
+//   capture thread and at the same time stops audio streaming.
+// - The same thread that called stop will call Close() where we cleanup
+//   and notify the audio manager, which likely will destroy this object.
+//
+// Implementation notes:
+//
+// - The minimum supported client is Windows Vista.
+// - This implementation is single-threaded, hence:
+//    o Construction and destruction must take place from the same thread.
+//    o It is recommended to call all APIs from the same thread as well.
+// - It is recommended to first acquire the native sample rate of the default
+//   input device and then use the same rate when creating this object. Use
+//   WASAPIAudioInputStream::HardwareSampleRate() to retrieve the sample rate.
+// - Calling Close() also leads to self destruction.
+//
+// Core Audio API details:
+//
+// - Utilized MMDevice interfaces:
+//     o IMMDeviceEnumerator
+//     o IMMDevice
+// - Utilized WASAPI interfaces:
+//     o IAudioClient
+//     o IAudioCaptureClient
+// - The stream is initialized in shared mode and the processing of the
+//   audio buffer is event driven.
+// - The Multimedia Class Scheduler service (MMCSS) is utilized to boost
+//   the priority of the capture thread.
+// - Audio applications that use the MMDevice API and WASAPI typically use
+//   the ISimpleAudioVolume interface to manage stream volume levels on a
+//   per-session basis. It is also possible to use of the IAudioEndpointVolume
+//   interface to control the master volume level of an audio endpoint device.
+//   This implementation is using the ISimpleAudioVolume interface.
+//   MSDN states that "In rare cases, a specialized audio application might
+//   require the use of the IAudioEndpointVolume".
+//
+#ifndef MEDIA_AUDIO_WIN_AUDIO_LOW_LATENCY_INPUT_WIN_H_
+#define MEDIA_AUDIO_WIN_AUDIO_LOW_LATENCY_INPUT_WIN_H_
+
+#include <Audioclient.h>
+#include <MMDeviceAPI.h>
+#include <endpointvolume.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include <memory>
+#include <string>
+
+#include "base/compiler_specific.h"
+#include "base/macros.h"
+#include "base/threading/non_thread_safe.h"
+#include "base/threading/platform_thread.h"
+#include "base/threading/simple_thread.h"
+#include "base/win/scoped_co_mem.h"
+#include "base/win/scoped_com_initializer.h"
+#include "base/win/scoped_comptr.h"
+#include "base/win/scoped_handle.h"
+#include "media/audio/agc_audio_stream.h"
+#include "media/base/audio_parameters.h"
+#include "media/base/media_export.h"
+
+namespace media {
+
+class AudioBus;
+class AudioManagerWin;
+
+// AudioInputStream implementation using Windows Core Audio APIs.
+class MEDIA_EXPORT WASAPIAudioInputStream
+    : public AgcAudioStream<AudioInputStream>,
+      public base::DelegateSimpleThread::Delegate,
+      NON_EXPORTED_BASE(public base::NonThreadSafe) {
+ public:
+  // The ctor takes all the usual parameters, plus |manager| which is the
+  // the audio manager who is creating this object.
+  WASAPIAudioInputStream(AudioManagerWin* manager,
+                         const AudioParameters& params,
+                         const std::string& device_id);
+
+  // The dtor is typically called by the AudioManager only and it is usually
+  // triggered by calling AudioInputStream::Close().
+  ~WASAPIAudioInputStream() override;
+
+  // Implementation of AudioInputStream.
+  bool Open() override;
+  void Start(AudioInputCallback* callback) override;
+  void Stop() override;
+  void Close() override;
+  double GetMaxVolume() override;
+  void SetVolume(double volume) override;
+  double GetVolume() override;
+  bool IsMuted() override;
+
+  bool started() const { return started_; }
+
+ private:
+  // DelegateSimpleThread::Delegate implementation.
+  void Run() override;
+
+  // Issues the OnError() callback to the |sink_|.
+  void HandleError(HRESULT err);
+
+  // The Open() method is divided into these sub methods.
+  HRESULT SetCaptureDevice();
+  HRESULT ActivateCaptureDevice();
+  HRESULT GetAudioEngineStreamFormat();
+  bool DesiredFormatIsSupported();
+  HRESULT InitializeAudioEngine();
+
+  // Our creator, the audio manager needs to be notified when we close.
+  AudioManagerWin* manager_;
+
+  // Capturing is driven by this thread (which has no message loop).
+  // All OnData() callbacks will be called from this thread.
+  base::DelegateSimpleThread* capture_thread_;
+
+  // Contains the desired audio format which is set up at construction.
+  WAVEFORMATEX format_;
+
+  bool opened_;
+  bool started_;
+
+  // Size in bytes of each audio frame (4 bytes for 16-bit stereo PCM)
+  size_t frame_size_;
+
+  // Size in audio frames of each audio packet where an audio packet
+  // is defined as the block of data which the user received in each
+  // OnData() callback.
+  size_t packet_size_frames_;
+
+  // Size in bytes of each audio packet.
+  size_t packet_size_bytes_;
+
+  // Length of the audio endpoint buffer.
+  uint32_t endpoint_buffer_size_frames_;
+
+  // Contains the unique name of the selected endpoint device.
+  // Note that AudioDeviceDescription::kDefaultDeviceId represents the default
+  // device role and is not a valid ID as such.
+  std::string device_id_;
+
+  // Conversion factor used in delay-estimation calculations.
+  // Converts a raw performance counter value to 100-nanosecond unit.
+  double perf_count_to_100ns_units_;
+
+  // Conversion factor used in delay-estimation calculations.
+  // Converts from milliseconds to audio frames.
+  double ms_to_frame_count_;
+
+  // Pointer to the object that will receive the recorded audio samples.
+  AudioInputCallback* sink_;
+
+  // Windows Multimedia Device (MMDevice) API interfaces.
+
+  // An IMMDevice interface which represents an audio endpoint device.
+  base::win::ScopedComPtr<IMMDevice> endpoint_device_;
+
+  // Windows Audio Session API (WASAPI) interfaces.
+
+  // An IAudioClient interface which enables a client to create and initialize
+  // an audio stream between an audio application and the audio engine.
+  base::win::ScopedComPtr<IAudioClient> audio_client_;
+
+  // Loopback IAudioClient doesn't support event-driven mode, so a separate
+  // IAudioClient is needed to receive notifications when data is available in
+  // the buffer. For loopback input |audio_client_| is used to receive data,
+  // while |audio_render_client_for_loopback_| is used to get notifications
+  // when a new buffer is ready. See comment in InitializeAudioEngine() for
+  // details.
+  base::win::ScopedComPtr<IAudioClient> audio_render_client_for_loopback_;
+
+  // The IAudioCaptureClient interface enables a client to read input data
+  // from a capture endpoint buffer.
+  base::win::ScopedComPtr<IAudioCaptureClient> audio_capture_client_;
+
+  // The ISimpleAudioVolume interface enables a client to control the
+  // master volume level of an audio session.
+  // The volume-level is a value in the range 0.0 to 1.0.
+  // This interface does only work with shared-mode streams.
+  base::win::ScopedComPtr<ISimpleAudioVolume> simple_audio_volume_;
+
+  // The IAudioEndpointVolume allows a client to control the volume level of
+  // the whole system.
+  base::win::ScopedComPtr<IAudioEndpointVolume> system_audio_volume_;
+
+  // The audio engine will signal this event each time a buffer has been
+  // recorded.
+  base::win::ScopedHandle audio_samples_ready_event_;
+
+  // This event will be signaled when capturing shall stop.
+  base::win::ScopedHandle stop_capture_event_;
+
+  // Extra audio bus used for storage of deinterleaved data for the OnData
+  // callback.
+  std::unique_ptr<media::AudioBus> audio_bus_;
+
+  // Never set it through external API. Only used when |device_id_| ==
+  // kLoopbackWithMuteDeviceId.
+  // True, if we have muted the system audio for the stream capturing, and
+  // indicate we need to unmute the system audio when stopping capturing.

[henrika (OOO until Aug 14), 2016/07/26 10:04:25]

..and indicates that we need to...

[qiangchen, 2016/07/26 16:53:02]

Done.

+  bool mute_done_;
+
+  DISALLOW_COPY_AND_ASSIGN(WASAPIAudioInputStream);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_AUDIO_WIN_AUDIO_LOW_LATENCY_INPUT_WIN_H_