Silence detection test for the Windows audio capturer.

remoting/host/audio_capturer_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.
+
+#include <audioclient.h>
+#include <mmdeviceapi.h>
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/timer.h"
+#include "base/win/scoped_co_mem.h"
+#include "base/win/scoped_com_initializer.h"
+#include "base/win/scoped_comptr.h"
+#include "remoting/host/audio_capturer.h"
+#include "remoting/proto/audio.pb.h"
+
+namespace remoting {
+
+class AudioCapturerWin : public AudioCapturer {
+ public:
+  AudioCapturerWin();
+  virtual ~AudioCapturerWin();
+
+  // AudioCapturer interface.
+  virtual bool Start(const PacketCapturedCallback& callback) OVERRIDE;
+  virtual void Stop() OVERRIDE;
+  virtual bool IsRunning() OVERRIDE;
+
+  static bool IsPacketOfSilence(const int16* samples, int number_of_samples);
+
+ private:
+  // Receives all packets from the audio capture endpoint buffer and pushes them
+  // to the network.
+  void DoCapture();
+
+  PacketCapturedCallback callback_;
+
+  AudioPacket::SamplingRate sampling_rate_;
+
+  scoped_ptr<base::RepeatingTimer<AudioCapturerWin> > capture_timer_;
+  base::TimeDelta audio_device_period_;
+
+  base::win::ScopedCoMem<WAVEFORMATEX> wave_format_ex_;
+  base::win::ScopedComPtr<IAudioCaptureClient> audio_capture_client_;
+  base::win::ScopedComPtr<IAudioClient> audio_client_;
+  base::win::ScopedComPtr<IMMDevice> mm_device_;
+  scoped_ptr<base::win::ScopedCOMInitializer> com_initializer_;
+
+  base::ThreadChecker thread_checker_;
+
+  DISALLOW_COPY_AND_ASSIGN(AudioCapturerWin);
+};
+
+}  // namespace remoting