Move media/audio files into media namespace

BUG=115187
TEST=compiles and runs without breaking audio tag; media_unittests, content_unittests

Review URL: https://chromiumcodereview.appspot.com/9805001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@130180 0039d316-1c4b-4281-b951-d872f2087c98

128 files changed, 535 insertions, 203 deletions

diff --git a/content/browser/browser_main_loop.cc b/content/browser/browser_main_loop.cc
index 78a971b..466c177 100644
--- a/content/browser/browser_main_loop.cc
+++ b/content/browser/browser_main_loop.cc
@@ -206,7 +206,7 @@ void ImmediateShutdownAndExitProcess() {
 }
 
 // static
-AudioManager* BrowserMainLoop::GetAudioManager() {
+media::AudioManager* BrowserMainLoop::GetAudioManager() {
   return g_current_browser_main_loop->audio_manager_.get();
 }
 
@@ -327,7 +327,7 @@ void BrowserMainLoop::MainMessageLoopStart() {
   hi_res_timer_manager_.reset(new HighResolutionTimerManager);
 
   network_change_notifier_.reset(net::NetworkChangeNotifier::Create());
-  audio_manager_.reset(AudioManager::Create());
+  audio_manager_.reset(media::AudioManager::Create());
   online_state_observer_.reset(new BrowserOnlineStateObserver);
 
 #if defined(OS_WIN)
diff --git a/content/browser/browser_main_loop.h b/content/browser/browser_main_loop.h
index 138d11e..f43e6eb 100644
--- a/content/browser/browser_main_loop.h
+++ b/content/browser/browser_main_loop.h
@@ -14,7 +14,6 @@
 #include "ui/base/win/scoped_ole_initializer.h"
 #endif
 
-class AudioManager;
 class BrowserOnlineStateObserver;
 class CommandLine;
 class HighResolutionTimerManager;
@@ -25,6 +24,10 @@ namespace base {
 class SystemMonitor;
 }
 
+namespace media {
+class AudioManager;
+}
+
 namespace net {
 class NetworkChangeNotifier;
 }
@@ -66,7 +69,7 @@ class BrowserMainLoop {
   int GetResultCode() const { return result_code_; }
 
   // Can be called on any thread.
-  static AudioManager* GetAudioManager();
+  static media::AudioManager* GetAudioManager();
 
  private:
   // For ShutdownThreadsAndCleanUp.
@@ -89,7 +92,7 @@ class BrowserMainLoop {
   scoped_ptr<base::SystemMonitor> system_monitor_;
   scoped_ptr<HighResolutionTimerManager> hi_res_timer_manager_;
   scoped_ptr<net::NetworkChangeNotifier> network_change_notifier_;
-  scoped_ptr<AudioManager> audio_manager_;
+  scoped_ptr<media::AudioManager> audio_manager_;
   // Per-process listener for online state changes.
   scoped_ptr<BrowserOnlineStateObserver> online_state_observer_;
 #if defined(OS_WIN)
diff --git a/content/browser/renderer_host/media/audio_input_device_manager.cc b/content/browser/renderer_host/media/audio_input_device_manager.cc
index d30ec3b..00e37f9a 100644
--- a/content/browser/renderer_host/media/audio_input_device_manager.cc
+++ b/content/browser/renderer_host/media/audio_input_device_manager.cc
@@ -21,7 +21,8 @@ const char AudioInputDeviceManager::kInvalidDeviceId[] = "";
 // Starting id for the first capture session.
 const int kFirstSessionId = AudioInputDeviceManager::kFakeOpenSessionId + 1;
 
-AudioInputDeviceManager::AudioInputDeviceManager(AudioManager* audio_manager)
+AudioInputDeviceManager::AudioInputDeviceManager(
+    media::AudioManager* audio_manager)
     : listener_(NULL),
       next_capture_session_id_(kFirstSessionId),
       audio_manager_(audio_manager) {
@@ -127,7 +128,7 @@ void AudioInputDeviceManager::Start(
   // the callback immediately.
   if (session_id == kFakeOpenSessionId) {
     event_handler->OnDeviceStarted(session_id,
-                                   AudioManagerBase::kDefaultDeviceId);
+                                   media::AudioManagerBase::kDefaultDeviceId);
     return;
   }
 
diff --git a/content/browser/renderer_host/media/audio_input_device_manager.h b/content/browser/renderer_host/media/audio_input_device_manager.h
index 5c8a396..96bff65 100644
--- a/content/browser/renderer_host/media/audio_input_device_manager.h
+++ b/content/browser/renderer_host/media/audio_input_device_manager.h
@@ -21,7 +21,9 @@
 #include "content/common/media/media_stream_options.h"
 #include "media/audio/audio_device_name.h"
 
+namespace media {
 class AudioManager;
+}
 
 namespace media_stream {
 
@@ -39,7 +41,7 @@ class CONTENT_EXPORT AudioInputDeviceManager
   static const int kInvalidSessionId;
   static const char kInvalidDeviceId[];
 
-  explicit AudioInputDeviceManager(AudioManager* audio_manager);
+  explicit AudioInputDeviceManager(media::AudioManager* audio_manager);
 
   // MediaStreamProvider implementation, called on IO thread.
   virtual void Register(MediaStreamProviderListener* listener) OVERRIDE;
@@ -72,7 +74,7 @@ class CONTENT_EXPORT AudioInputDeviceManager
   typedef std::map<int, media::AudioDeviceName> AudioInputDeviceMap;
   AudioInputDeviceMap devices_;
   // TODO(tommi): Is it necessary to store this as a member?
-  AudioManager* audio_manager_;
+  media::AudioManager* audio_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioInputDeviceManager);
 };
diff --git a/content/browser/renderer_host/media/audio_input_device_manager_unittest.cc b/content/browser/renderer_host/media/audio_input_device_manager_unittest.cc
index 173606a..fe57150 100644
--- a/content/browser/renderer_host/media/audio_input_device_manager_unittest.cc
+++ b/content/browser/renderer_host/media/audio_input_device_manager_unittest.cc
@@ -105,7 +105,7 @@ class AudioInputDeviceManagerTest : public testing::Test {
     message_loop_.reset(new MessageLoop(MessageLoop::TYPE_IO));
     io_thread_.reset(new BrowserThreadImpl(BrowserThread::IO,
                                            message_loop_.get()));
-    audio_manager_.reset(AudioManager::Create());
+    audio_manager_.reset(media::AudioManager::Create());
 
     manager_ = new AudioInputDeviceManager(audio_manager_.get());
     audio_input_listener_.reset(new MockAudioInputDeviceManagerListener());
@@ -129,7 +129,7 @@ class AudioInputDeviceManagerTest : public testing::Test {
   scoped_ptr<BrowserThreadImpl> io_thread_;
   scoped_refptr<AudioInputDeviceManager> manager_;
   scoped_ptr<MockAudioInputDeviceManagerListener> audio_input_listener_;
-  scoped_ptr<AudioManager> audio_manager_;
+  scoped_ptr<media::AudioManager> audio_manager_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AudioInputDeviceManagerTest);
@@ -414,11 +414,11 @@ TEST_F(AudioInputDeviceManagerTest, StartDeviceTwice) {
   manager_->Start(second_session_id, second_event_handler.get());
   EXPECT_CALL(*first_event_handler,
               DeviceStarted(first_session_id,
-                            AudioManagerBase::kDefaultDeviceId))
+                            media::AudioManagerBase::kDefaultDeviceId))
       .Times(1);
   EXPECT_CALL(*second_event_handler,
               DeviceStarted(second_session_id,
-                            AudioManagerBase::kDefaultDeviceId))
+                            media::AudioManagerBase::kDefaultDeviceId))
       .Times(1);
   message_loop_->RunAllPending();
 
@@ -502,7 +502,7 @@ TEST_F(AudioInputDeviceManagerTest, StartSessionTwice) {
   manager_->Start(session_id, audio_input_event_handler.get());
   EXPECT_CALL(*audio_input_event_handler,
               DeviceStarted(session_id,
-                            AudioManagerBase::kDefaultDeviceId))
+                            media::AudioManagerBase::kDefaultDeviceId))
       .Times(1);
   message_loop_->RunAllPending();
 
diff --git a/content/browser/renderer_host/media/audio_input_renderer_host.cc b/content/browser/renderer_host/media/audio_input_renderer_host.cc
index 121a5ac..3465202 100644
--- a/content/browser/renderer_host/media/audio_input_renderer_host.cc
+++ b/content/browser/renderer_host/media/audio_input_renderer_host.cc
@@ -25,7 +25,7 @@ AudioInputRendererHost::AudioEntry::~AudioEntry() {}
 
 AudioInputRendererHost::AudioInputRendererHost(
     content::ResourceContext* resource_context,
-    AudioManager* audio_manager)
+    media::AudioManager* audio_manager)
     : resource_context_(resource_context),
       audio_manager_(audio_manager) {
 }
@@ -114,8 +114,8 @@ void AudioInputRendererHost::DoCompleteCreation(
     return;
   }
 
-  AudioInputSyncWriter* writer =
-      static_cast<AudioInputSyncWriter*>(entry->writer.get());
+  media::AudioInputSyncWriter* writer =
+      static_cast<media::AudioInputSyncWriter*>(entry->writer.get());
 
 #if defined(OS_WIN)
   base::SyncSocket::Handle foreign_socket_handle;
@@ -197,16 +197,15 @@ void AudioInputRendererHost::OnStartDevice(int stream_id, int session_id) {
   audio_input_man->Start(session_id, this);
 }
 
-void AudioInputRendererHost::OnCreateStream(int stream_id,
-                                            const AudioParameters& params,
-                                            const std::string& device_id,
-                                            bool automatic_gain_control) {
+void AudioInputRendererHost::OnCreateStream(
+    int stream_id, const media::AudioParameters& params,
+    const std::string& device_id, bool automatic_gain_control) {
   VLOG(1) << "AudioInputRendererHost::OnCreateStream(stream_id="
           << stream_id << ")";
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   DCHECK(LookupById(stream_id) == NULL);
 
-  AudioParameters audio_params(params);
+  media::AudioParameters audio_params(params);
 
   DCHECK_GT(audio_params.frames_per_buffer(), 0);
   uint32 buffer_size = audio_params.GetBytesPerBuffer();
@@ -214,7 +213,7 @@ void AudioInputRendererHost::OnCreateStream(int stream_id,
   // Create a new AudioEntry structure.
   scoped_ptr<AudioEntry> entry(new AudioEntry());
 
-  uint32 mem_size = sizeof(AudioInputBufferParameters) + buffer_size;
+  uint32 mem_size = sizeof(media::AudioInputBufferParameters) + buffer_size;
 
   // Create the shared memory and share it with the renderer process
   // using a new SyncWriter object.
@@ -224,8 +223,8 @@ void AudioInputRendererHost::OnCreateStream(int stream_id,
     return;
   }
 
-  scoped_ptr<AudioInputSyncWriter> writer(
-      new AudioInputSyncWriter(&entry->shared_memory));
+  scoped_ptr<media::AudioInputSyncWriter> writer(
+      new media::AudioInputSyncWriter(&entry->shared_memory));
 
   if (!writer->Init()) {
     SendErrorMessage(stream_id);
diff --git a/content/browser/renderer_host/media/audio_input_renderer_host.h b/content/browser/renderer_host/media/audio_input_renderer_host.h
index 5a9cc6b..f8351c8 100644
--- a/content/browser/renderer_host/media/audio_input_renderer_host.h
+++ b/content/browser/renderer_host/media/audio_input_renderer_host.h
@@ -68,8 +68,10 @@ namespace content {
 class ResourceContext;
 }
 
+namespace media {
 class AudioManager;
 class AudioParameters;
+}
 
 class CONTENT_EXPORT AudioInputRendererHost
     : public content::BrowserMessageFilter,
@@ -99,7 +101,7 @@ class CONTENT_EXPORT AudioInputRendererHost
 
   // Called from UI thread from the owner of this object.
   AudioInputRendererHost(content::ResourceContext* resource_context,
-                         AudioManager* audio_manager);
+                         media::AudioManager* audio_manager);
 
   // content::BrowserMessageFilter implementation.
   virtual void OnChannelClosing() OVERRIDE;
@@ -139,7 +141,7 @@ class CONTENT_EXPORT AudioInputRendererHost
   // successful this object would keep an internal entry of the stream for the
   // required properties.
   void OnCreateStream(int stream_id,
-                      const AudioParameters& params,
+                      const media::AudioParameters& params,
                       const std::string& device_id,
                       bool automatic_gain_control);
 
@@ -197,7 +199,7 @@ class CONTENT_EXPORT AudioInputRendererHost
 
   // Used to get an instance of AudioInputDeviceManager.
   content::ResourceContext* resource_context_;
-  AudioManager* audio_manager_;
+  media::AudioManager* audio_manager_;
 
   // A map of stream IDs to audio sources.
   typedef std::map<int, AudioEntry*> AudioEntryMap;
diff --git a/content/browser/renderer_host/media/audio_input_sync_writer.cc b/content/browser/renderer_host/media/audio_input_sync_writer.cc
index d720017..87751d7 100644
--- a/content/browser/renderer_host/media/audio_input_sync_writer.cc
+++ b/content/browser/renderer_host/media/audio_input_sync_writer.cc
@@ -9,6 +9,8 @@
 #include "base/process_util.h"
 #include "base/shared_memory.h"
 
+namespace media {
+
 AudioInputSyncWriter::AudioInputSyncWriter(base::SharedMemory* shared_memory)
     : shared_memory_(shared_memory) {
 }
@@ -64,3 +66,5 @@ bool AudioInputSyncWriter::PrepareForeignSocketHandle(
 }
 
 #endif
+
+}  // namespace media
diff --git a/content/browser/renderer_host/media/audio_input_sync_writer.h b/content/browser/renderer_host/media/audio_input_sync_writer.h
index 77acd50..1b7a609 100644
--- a/content/browser/renderer_host/media/audio_input_sync_writer.h
+++ b/content/browser/renderer_host/media/audio_input_sync_writer.h
@@ -15,6 +15,7 @@ namespace base {
 class SharedMemory;
 }
 
+namespace media {
 // A AudioInputController::SyncWriter implementation using SyncSocket. This
 // is used by AudioInputController to provide a low latency data source for
 // transmitting audio packets between the browser process and the renderer
@@ -51,4 +52,6 @@ class AudioInputSyncWriter : public media::AudioInputController::SyncWriter {
   DISALLOW_IMPLICIT_CONSTRUCTORS(AudioInputSyncWriter);
 };
 
+}  // namespace media
+
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_INPUT_SYNC_WRITER_H_
diff --git a/content/browser/renderer_host/media/audio_renderer_host.cc b/content/browser/renderer_host/media/audio_renderer_host.cc
index 290b94a..c59ef44 100644
--- a/content/browser/renderer_host/media/audio_renderer_host.cc
+++ b/content/browser/renderer_host/media/audio_renderer_host.cc
@@ -27,7 +27,7 @@ AudioRendererHost::AudioEntry::~AudioEntry() {}
 ///////////////////////////////////////////////////////////////////////////////
 // AudioRendererHost implementations.
 AudioRendererHost::AudioRendererHost(
-    AudioManager* audio_manager,
+    media::AudioManager* audio_manager,
     content::MediaObserver* media_observer)
     : audio_manager_(audio_manager),
       media_observer_(media_observer) {
@@ -192,11 +192,11 @@ bool AudioRendererHost::OnMessageReceived(const IPC::Message& message,
 }
 
 void AudioRendererHost::OnCreateStream(
-    int stream_id, const AudioParameters& params) {
+    int stream_id, const media::AudioParameters& params) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   DCHECK(LookupById(stream_id) == NULL);
 
-  AudioParameters audio_params(params);
+  media::AudioParameters audio_params(params);
   DCHECK_GT(audio_params.frames_per_buffer(), 0);
 
   uint32 buffer_size = audio_params.GetBytesPerBuffer();
diff --git a/content/browser/renderer_host/media/audio_renderer_host.h b/content/browser/renderer_host/media/audio_renderer_host.h
index a506531..cea2f3a 100644
--- a/content/browser/renderer_host/media/audio_renderer_host.h
+++ b/content/browser/renderer_host/media/audio_renderer_host.h
@@ -53,14 +53,16 @@
 #include "media/audio/audio_output_controller.h"
 #include "media/audio/simple_sources.h"
 
-class AudioManager;
-class AudioParameters;
-
 namespace content {
 class MediaObserver;
 class ResourceContext;
 }  // namespace content
 
+namespace media {
+class AudioManager;
+class AudioParameters;
+}
+
 class CONTENT_EXPORT AudioRendererHost
     : public content::BrowserMessageFilter,
       public media::AudioOutputController::EventHandler {
@@ -89,7 +91,7 @@ class CONTENT_EXPORT AudioRendererHost
   typedef std::map<int, AudioEntry*> AudioEntryMap;
 
   // Called from UI thread from the owner of this object.
-  AudioRendererHost(AudioManager* audio_manager,
+  AudioRendererHost(media::AudioManager* audio_manager,
                     content::MediaObserver* media_observer);
 
   // content::BrowserMessageFilter implementation.
@@ -121,7 +123,7 @@ class CONTENT_EXPORT AudioRendererHost
   // Creates an audio output stream with the specified format. If this call is
   // successful this object would keep an internal entry of the stream for the
   // required properties.
-  void OnCreateStream(int stream_id, const AudioParameters& params);
+  void OnCreateStream(int stream_id, const media::AudioParameters& params);
 
   // Play the audio stream referenced by |stream_id|.
   void OnPlayStream(int stream_id);
@@ -178,7 +180,7 @@ class CONTENT_EXPORT AudioRendererHost
   // A map of stream IDs to audio sources.
   AudioEntryMap audio_entries_;
 
-  AudioManager* audio_manager_;
+  media::AudioManager* audio_manager_;
   content::MediaObserver* media_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererHost);
diff --git a/content/browser/renderer_host/media/audio_renderer_host_unittest.cc b/content/browser/renderer_host/media/audio_renderer_host_unittest.cc
index 71a5063..6a1287a 100644
--- a/content/browser/renderer_host/media/audio_renderer_host_unittest.cc
+++ b/content/browser/renderer_host/media/audio_renderer_host_unittest.cc
@@ -43,7 +43,7 @@ static bool IsRunningHeadless() {
 class MockAudioRendererHost : public AudioRendererHost {
  public:
   explicit MockAudioRendererHost(
-      AudioManager* audio_manager,
+      media::AudioManager* audio_manager,
       content::MediaObserver* media_observer)
       : AudioRendererHost(audio_manager, media_observer),
         shared_memory_length_(0) {
@@ -161,7 +161,7 @@ class AudioRendererHostTest : public testing::Test {
                                            message_loop_.get()));
     ui_thread_.reset(new BrowserThreadImpl(BrowserThread::UI,
                                            message_loop_.get()));
-    audio_manager_.reset(AudioManager::Create());
+    audio_manager_.reset(media::AudioManager::Create());
     observer_.reset(new MockMediaObserver());
     host_ = new MockAudioRendererHost(audio_manager_.get(), observer_.get());
 
@@ -195,15 +195,16 @@ class AudioRendererHostTest : public testing::Test {
     EXPECT_CALL(*host_, OnStreamCreated(kStreamId, _))
         .WillOnce(QuitMessageLoop(message_loop_.get()));
 
-    AudioParameters::Format format;
+    media::AudioParameters::Format format;
     if (mock_stream_)
-      format = AudioParameters::AUDIO_MOCK;
+      format = media::AudioParameters::AUDIO_MOCK;
     else
-      format = AudioParameters::AUDIO_PCM_LINEAR;
+      format = media::AudioParameters::AUDIO_PCM_LINEAR;
 
-    AudioParameters params(format, CHANNEL_LAYOUT_STEREO,
-                           AudioParameters::kAudioCDSampleRate, 16,
-                           AudioParameters::kAudioCDSampleRate / 10);
+    media::AudioParameters params(
+        format, CHANNEL_LAYOUT_STEREO,
+        media::AudioParameters::kAudioCDSampleRate, 16,
+        media::AudioParameters::kAudioCDSampleRate / 10);
 
     // Send a create stream message to the audio output stream and wait until
     // we receive the created message.
@@ -279,7 +280,7 @@ class AudioRendererHostTest : public testing::Test {
   }
 
   // Called on the main thread.
-  static void PostQuitOnAudioThread(AudioManager* audio_manager,
+  static void PostQuitOnAudioThread(media::AudioManager* audio_manager,
                                     MessageLoop* message_loop) {
     audio_manager->GetMessageLoop()->PostTask(FROM_HERE,
         base::Bind(&PostQuitMessageLoop, message_loop));
@@ -290,7 +291,7 @@ class AudioRendererHostTest : public testing::Test {
   // current thread. It is used to synchronize with the audio thread when we are
   // closing an audio stream.
   void SyncWithAudioThread() {
-    // Don't use scoped_refptr to addref the AudioManager when posting
+    // Don't use scoped_refptr to addref the media::AudioManager when posting
     // to the thread that itself owns.
     message_loop_->PostTask(
         FROM_HERE, base::Bind(&PostQuitOnAudioThread,
@@ -310,7 +311,7 @@ class AudioRendererHostTest : public testing::Test {
   scoped_ptr<MessageLoop> message_loop_;
   scoped_ptr<BrowserThreadImpl> io_thread_;
   scoped_ptr<BrowserThreadImpl> ui_thread_;
-  scoped_ptr<AudioManager> audio_manager_;
+  scoped_ptr<media::AudioManager> audio_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererHostTest);
 };
@@ -361,7 +362,8 @@ TEST_F(AudioRendererHostTest, SetVolume) {
 
   // Expect the volume is set.
   if (IsRunningHeadless()) {
-    EXPECT_EQ(0.5, FakeAudioOutputStream::GetCurrentFakeStream()->volume());
+    EXPECT_EQ(0.5,
+              media::FakeAudioOutputStream::GetCurrentFakeStream()->volume());
   }
   Close();
 }
diff --git a/content/browser/renderer_host/media/media_stream_dispatcher_host.cc b/content/browser/renderer_host/media/media_stream_dispatcher_host.cc
index f48f826..67b7044 100644
--- a/content/browser/renderer_host/media/media_stream_dispatcher_host.cc
+++ b/content/browser/renderer_host/media/media_stream_dispatcher_host.cc
@@ -26,7 +26,7 @@ struct MediaStreamDispatcherHost::StreamRequest {
 MediaStreamDispatcherHost::MediaStreamDispatcherHost(
     content::ResourceContext* resource_context,
     int render_process_id,
-    AudioManager* audio_manager)
+    media::AudioManager* audio_manager)
     : resource_context_(resource_context),
       render_process_id_(render_process_id),
       audio_manager_(audio_manager) {
diff --git a/content/browser/renderer_host/media/media_stream_dispatcher_host.h b/content/browser/renderer_host/media/media_stream_dispatcher_host.h
index aa44969..1ecd13d 100644
--- a/content/browser/renderer_host/media/media_stream_dispatcher_host.h
+++ b/content/browser/renderer_host/media/media_stream_dispatcher_host.h
@@ -30,7 +30,7 @@ class CONTENT_EXPORT MediaStreamDispatcherHost
  public:
   MediaStreamDispatcherHost(content::ResourceContext* resource_context,
                             int render_process_id,
-                            AudioManager* audio_manager);
+                            media::AudioManager* audio_manager);
   virtual ~MediaStreamDispatcherHost();
 
   // MediaStreamRequester implementation.
@@ -80,7 +80,7 @@ class CONTENT_EXPORT MediaStreamDispatcherHost
 
   content::ResourceContext* resource_context_;
   int render_process_id_;
-  AudioManager* audio_manager_;
+  media::AudioManager* audio_manager_;
 
   struct StreamRequest;
   typedef std::map<std::string, StreamRequest> StreamMap;
diff --git a/content/browser/renderer_host/media/media_stream_dispatcher_host_unittest.cc b/content/browser/renderer_host/media/media_stream_dispatcher_host_unittest.cc
index 9c699ed..50f7356 100644
--- a/content/browser/renderer_host/media/media_stream_dispatcher_host_unittest.cc
+++ b/content/browser/renderer_host/media/media_stream_dispatcher_host_unittest.cc
@@ -37,7 +37,7 @@ class MockMediaStreamDispatcherHost : public MediaStreamDispatcherHost {
  public:
   MockMediaStreamDispatcherHost(content::ResourceContext* resource_context,
                                 MessageLoop* message_loop,
-                                AudioManager* audio_manager)
+                                media::AudioManager* audio_manager)
       : MediaStreamDispatcherHost(resource_context, kProcessId, audio_manager),
         message_loop_(message_loop) {}
   virtual ~MockMediaStreamDispatcherHost() {}
@@ -153,7 +153,7 @@ class MediaStreamDispatcherHostTest : public testing::Test {
     io_thread_.reset(new BrowserThreadImpl(BrowserThread::IO,
                                            message_loop_.get()));
 
-    audio_manager_.reset(AudioManager::Create());
+    audio_manager_.reset(media::AudioManager::Create());
 
     // Make sure we use fake devices to avoid long delays.
     MediaStreamManager::GetForResourceContext(
@@ -201,7 +201,7 @@ class MediaStreamDispatcherHostTest : public testing::Test {
   scoped_ptr<MessageLoop> message_loop_;
   scoped_ptr<BrowserThreadImpl> ui_thread_;
   scoped_ptr<BrowserThreadImpl> io_thread_;
-  scoped_ptr<AudioManager> audio_manager_;
+  scoped_ptr<media::AudioManager> audio_manager_;
   content::MockResourceContext resource_context_;
 };
 
diff --git a/content/browser/renderer_host/media/media_stream_manager.cc b/content/browser/renderer_host/media/media_stream_manager.cc
index 82c0763..994725b 100644
--- a/content/browser/renderer_host/media/media_stream_manager.cc
+++ b/content/browser/renderer_host/media/media_stream_manager.cc
@@ -101,7 +101,7 @@ struct MediaStreamManager::DeviceRequest {
 // static
 MediaStreamManager* MediaStreamManager::GetForResourceContext(
     content::ResourceContext* resource_context,
-    AudioManager* audio_manager) {
+    media::AudioManager* audio_manager) {
   MediaStreamManager* rv = static_cast<MediaStreamManager*>(
       resource_context->GetUserData(kMediaStreamManagerKeyName));
   if (!rv) {
@@ -111,7 +111,7 @@ MediaStreamManager* MediaStreamManager::GetForResourceContext(
   return rv;
 }
 
-MediaStreamManager::MediaStreamManager(AudioManager* audio_manager)
+MediaStreamManager::MediaStreamManager(media::AudioManager* audio_manager)
     : ALLOW_THIS_IN_INITIALIZER_LIST(
           device_settings_(new MediaStreamDeviceSettings(this))),
       enumeration_in_progress_(content::NUM_MEDIA_STREAM_DEVICE_TYPES, false),
diff --git a/content/browser/renderer_host/media/media_stream_manager.h b/content/browser/renderer_host/media/media_stream_manager.h
index b73e670..d1e9ccc 100644
--- a/content/browser/renderer_host/media/media_stream_manager.h
+++ b/content/browser/renderer_host/media/media_stream_manager.h
@@ -35,12 +35,14 @@
 #include "content/common/media/media_stream_options.h"
 #include "content/common/content_export.h"
 
-class AudioManager;
-
 namespace content {
 class ResourceContext;
 }
 
+namespace media {
+class AudioManager;
+}
+
 namespace media_stream {
 
 class AudioInputDeviceManager;
@@ -61,9 +63,9 @@ class CONTENT_EXPORT MediaStreamManager
   // been created yet, it will be constructed with the given AudioManager.
   static MediaStreamManager* GetForResourceContext(
       content::ResourceContext* resource_context,
-      AudioManager* audio_manager);
+      media::AudioManager* audio_manager);
 
-  explicit MediaStreamManager(AudioManager* audio_manager);
+  explicit MediaStreamManager(media::AudioManager* audio_manager);
   virtual ~MediaStreamManager();
 
   // Used to access VideoCaptureManager.
@@ -151,7 +153,7 @@ class CONTENT_EXPORT MediaStreamManager
   // All non-closed request.
   typedef std::map<std::string, DeviceRequest> DeviceRequests;
   DeviceRequests requests_;
-  AudioManager* audio_manager_;
+  media::AudioManager* audio_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaStreamManager);
 };
diff --git a/content/browser/renderer_host/media/video_capture_host.cc b/content/browser/renderer_host/media/video_capture_host.cc
index 3efcd7c..09f6981 100644
--- a/content/browser/renderer_host/media/video_capture_host.cc
+++ b/content/browser/renderer_host/media/video_capture_host.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -38,7 +38,7 @@ struct VideoCaptureHost::Entry {
 };
 
 VideoCaptureHost::VideoCaptureHost(content::ResourceContext* resource_context,
-                                   AudioManager* audio_manager)
+                                   media::AudioManager* audio_manager)
     : resource_context_(resource_context),
       audio_manager_(audio_manager) {
 }
diff --git a/content/browser/renderer_host/media/video_capture_host.h b/content/browser/renderer_host/media/video_capture_host.h
index bea1657..5e59722 100644
--- a/content/browser/renderer_host/media/video_capture_host.h
+++ b/content/browser/renderer_host/media/video_capture_host.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 //
@@ -45,18 +45,20 @@
 #include "content/public/browser/browser_message_filter.h"
 #include "ipc/ipc_message.h"
 
-class AudioManager;
-
 namespace content {
 class ResourceContext;
 }  // namespace content
 
+namespace media {
+class AudioManager;
+}
+
 class CONTENT_EXPORT VideoCaptureHost
     : public content::BrowserMessageFilter,
       public VideoCaptureControllerEventHandler {
  public:
   explicit VideoCaptureHost(content::ResourceContext* resource_context,
-                            AudioManager* audio_manager);
+                            media::AudioManager* audio_manager);
 
   // content::BrowserMessageFilter implementation.
   virtual void OnChannelClosing() OVERRIDE;
@@ -145,7 +147,7 @@ class CONTENT_EXPORT VideoCaptureHost
 
   // Used to get a pointer to VideoCaptureManager to start/stop capture devices.
   content::ResourceContext* resource_context_;
-  AudioManager* audio_manager_;
+  media::AudioManager* audio_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoCaptureHost);
 };
diff --git a/content/browser/renderer_host/media/video_capture_host_unittest.cc b/content/browser/renderer_host/media/video_capture_host_unittest.cc
index 4b91bf4..635b1bd 100644
--- a/content/browser/renderer_host/media/video_capture_host_unittest.cc
+++ b/content/browser/renderer_host/media/video_capture_host_unittest.cc
@@ -72,7 +72,7 @@ class DumpVideo {
 class MockVideoCaptureHost : public VideoCaptureHost {
  public:
   MockVideoCaptureHost(content::ResourceContext* resource_context,
-                       AudioManager* audio_manager)
+                       media::AudioManager* audio_manager)
       : VideoCaptureHost(resource_context, audio_manager),
         return_buffers_(false),
         dump_video_(false) {}
@@ -205,7 +205,7 @@ class VideoCaptureHostTest : public testing::Test {
     io_thread_.reset(new BrowserThreadImpl(BrowserThread::IO,
                                            message_loop_.get()));
 
-    audio_manager_.reset(AudioManager::Create());
+    audio_manager_.reset(media::AudioManager::Create());
 
 #ifndef TEST_REAL_CAPTURE_DEVICE
     media_stream::MediaStreamManager::GetForResourceContext(
@@ -246,7 +246,7 @@ class VideoCaptureHostTest : public testing::Test {
   // Called on the main thread.
   static void PostQuitOnVideoCaptureManagerThread(
       MessageLoop* message_loop, content::ResourceContext* resource_context,
-      AudioManager* audio_manager) {
+      media:: AudioManager* audio_manager) {
     media_stream::MediaStreamManager* manager =
         media_stream::MediaStreamManager::GetForResourceContext(
             resource_context, audio_manager);
@@ -362,7 +362,7 @@ class VideoCaptureHostTest : public testing::Test {
   scoped_ptr<MessageLoop> message_loop_;
   scoped_ptr<BrowserThreadImpl> ui_thread_;
   scoped_ptr<BrowserThreadImpl> io_thread_;
-  scoped_ptr<AudioManager> audio_manager_;
+  scoped_ptr<media::AudioManager> audio_manager_;
   content::MockResourceContext resource_context_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoCaptureHostTest);
diff --git a/content/browser/renderer_host/render_message_filter.cc b/content/browser/renderer_host/render_message_filter.cc
index a0dc2a3..91f37ae 100644
--- a/content/browser/renderer_host/render_message_filter.cc
+++ b/content/browser/renderer_host/render_message_filter.cc
@@ -692,7 +692,7 @@ void RenderMessageFilter::OnGetHardwareBufferSize(uint32* buffer_size) {
 void RenderMessageFilter::OnGetHardwareInputSampleRate(int* sample_rate) {
   // TODO(henrika): add support for all available input devices.
   *sample_rate = media::GetAudioInputHardwareSampleRate(
-      AudioManagerBase::kDefaultDeviceId);
+      media::AudioManagerBase::kDefaultDeviceId);
 }
 
 void RenderMessageFilter::OnGetHardwareSampleRate(int* sample_rate) {
@@ -703,7 +703,7 @@ void RenderMessageFilter::OnGetHardwareInputChannelLayout(
     ChannelLayout* layout) {
   // TODO(henrika): add support for all available input devices.
   *layout = media::GetAudioInputHardwareChannelLayout(
-      AudioManagerBase::kDefaultDeviceId);
+      media::AudioManagerBase::kDefaultDeviceId);
 }
 
 void RenderMessageFilter::OnDownloadUrl(const IPC::Message& message,
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index a3fa88a..57edc18 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -471,7 +471,8 @@ void RenderProcessHostImpl::CreateMessageFilters() {
 #if !defined(OS_ANDROID)
   // TODO(dtrainor, klobag): Enable this when content::BrowserMainLoop gets
   // included in Android builds.  Tracked via 115941.
-  AudioManager* audio_manager = content::BrowserMainLoop::GetAudioManager();
+  media::AudioManager* audio_manager =
+      content::BrowserMainLoop::GetAudioManager();
   channel_->AddFilter(new AudioInputRendererHost(
       resource_context, audio_manager));
   channel_->AddFilter(new AudioRendererHost(audio_manager, media_observer));
diff --git a/content/browser/speech/input_tag_speech_dispatcher_host.cc b/content/browser/speech/input_tag_speech_dispatcher_host.cc
index 7c10270..6ec3be0 100644
--- a/content/browser/speech/input_tag_speech_dispatcher_host.cc
+++ b/content/browser/speech/input_tag_speech_dispatcher_host.cc
@@ -118,7 +118,7 @@ InputTagSpeechDispatcherHost::InputTagSpeechDispatcherHost(
     int render_process_id,
     net::URLRequestContextGetter* context_getter,
     content::SpeechRecognitionPreferences* recognition_preferences,
-    AudioManager* audio_manager)
+    media::AudioManager* audio_manager)
     : render_process_id_(render_process_id),
       may_have_pending_requests_(false),
       context_getter_(context_getter),
diff --git a/content/browser/speech/input_tag_speech_dispatcher_host.h b/content/browser/speech/input_tag_speech_dispatcher_host.h
index 61d68b0..c988faf 100644
--- a/content/browser/speech/input_tag_speech_dispatcher_host.h
+++ b/content/browser/speech/input_tag_speech_dispatcher_host.h
@@ -10,7 +10,6 @@
 #include "content/public/browser/browser_message_filter.h"
 #include "net/url_request/url_request_context_getter.h"
 
-class AudioManager;
 struct InputTagSpeechHostMsg_StartRecognition_Params;
 
 namespace content {
@@ -18,6 +17,10 @@ class SpeechRecognitionPreferences;
 struct SpeechRecognitionResult;
 }
 
+namespace media {
+class AudioManager;
+}
+
 namespace speech {
 
 class SpeechRecognitionManagerImpl;
@@ -34,7 +37,7 @@ class CONTENT_EXPORT InputTagSpeechDispatcherHost
       int render_process_id,
       net::URLRequestContextGetter* context_getter,
       content::SpeechRecognitionPreferences* recognition_preferences,
-      AudioManager* audio_manager);
+      media::AudioManager* audio_manager);
 
   // Methods called by SpeechRecognitionManagerImpl.
   void SetRecognitionResult(int caller_id,
@@ -66,7 +69,7 @@ class CONTENT_EXPORT InputTagSpeechDispatcherHost
 
   scoped_refptr<net::URLRequestContextGetter> context_getter_;
   scoped_refptr<content::SpeechRecognitionPreferences> recognition_preferences_;
-  AudioManager* audio_manager_;
+  media::AudioManager* audio_manager_;
 
   static SpeechRecognitionManagerImpl* manager_;
 
diff --git a/content/browser/speech/speech_recognition_manager_impl.cc b/content/browser/speech/speech_recognition_manager_impl.cc
index e9d9d01..7600b50 100644
--- a/content/browser/speech/speech_recognition_manager_impl.cc
+++ b/content/browser/speech/speech_recognition_manager_impl.cc
@@ -114,7 +114,7 @@ void SpeechRecognitionManagerImpl::ShowAudioInputSettings() {
     return;
   }
 
-  AudioManager* audio_manager = BrowserMainLoop::GetAudioManager();
+  media::AudioManager* audio_manager = BrowserMainLoop::GetAudioManager();
   DCHECK(audio_manager->CanShowAudioInputSettings());
   if (audio_manager->CanShowAudioInputSettings())
     audio_manager->ShowAudioInputSettings();
diff --git a/content/browser/speech/speech_recognizer_impl.cc b/content/browser/speech/speech_recognizer_impl.cc
index 05f81e7..07bd75e 100644
--- a/content/browser/speech/speech_recognizer_impl.cc
+++ b/content/browser/speech/speech_recognizer_impl.cc
@@ -23,6 +23,7 @@ using content::SpeechRecognitionEventListener;
 using content::SpeechRecognitionResult;
 using content::SpeechRecognizer;
 using media::AudioInputController;
+using media::AudioManager;
 
 namespace {
 
@@ -137,13 +138,12 @@ void SpeechRecognizerImpl::StartRecognition() {
   endpointer_.SetEnvironmentEstimationMode();
 
   AudioManager* audio_manager = (testing_audio_manager_ != NULL) ?
-                                 testing_audio_manager_ :
-                                 BrowserMainLoop::GetAudioManager();
+      testing_audio_manager_ : BrowserMainLoop::GetAudioManager();
   const int samples_per_packet = kAudioSampleRate *
       GoogleOneShotRemoteEngine::kAudioPacketIntervalMs / 1000;
-  AudioParameters params(AudioParameters::AUDIO_PCM_LINEAR, kChannelLayout,
-                         kAudioSampleRate, kNumBitsPerAudioSample,
-                         samples_per_packet);
+  media::AudioParameters params(
+      media::AudioParameters::AUDIO_PCM_LINEAR, kChannelLayout,
+      kAudioSampleRate, kNumBitsPerAudioSample, samples_per_packet);
   audio_controller_ = AudioInputController::Create(audio_manager, this, params);
   DCHECK(audio_controller_.get());
   VLOG(1) << "SpeechRecognizer starting record.";
diff --git a/content/browser/speech/speech_recognizer_impl.h b/content/browser/speech/speech_recognizer_impl.h
index eed04bc..516dfea 100644
--- a/content/browser/speech/speech_recognizer_impl.h
+++ b/content/browser/speech/speech_recognizer_impl.h
@@ -22,6 +22,7 @@ struct SpeechRecognitionResult;
 
 namespace media {
 class AudioInputController;
+class AudioManager;
 }
 
 namespace speech {
@@ -91,10 +92,10 @@ class CONTENT_EXPORT SpeechRecognizerImpl
   // without blocking the IO thread.
   void CloseAudioControllerAsynchronously();
 
-  void SetAudioManagerForTesting(AudioManager* audio_manager);
+  void SetAudioManagerForTesting(media::AudioManager* audio_manager);
 
   content::SpeechRecognitionEventListener* listener_;
-  AudioManager* testing_audio_manager_;
+  media::AudioManager* testing_audio_manager_;
   scoped_ptr<SpeechRecognitionEngine> recognition_engine_;
   Endpointer endpointer_;
   scoped_refptr<media::AudioInputController> audio_controller_;
diff --git a/content/browser/speech/speech_recognizer_impl_unittest.cc b/content/browser/speech/speech_recognizer_impl_unittest.cc
index d553064..01b7e4c 100644
--- a/content/browser/speech/speech_recognizer_impl_unittest.cc
+++ b/content/browser/speech/speech_recognizer_impl_unittest.cc
@@ -20,12 +20,16 @@
 using content::BrowserThread;
 using content::BrowserThreadImpl;
 using media::AudioInputController;
+using media::AudioInputStream;
+using media::AudioManager;
+using media::AudioOutputStream;
+using media::AudioParameters;
 using media::TestAudioInputController;
 using media::TestAudioInputControllerFactory;
 
 namespace {
 
-class MockAudioManager : public AudioManagerBase {
+class MockAudioManager : public media::AudioManagerBase {
  public:
   MockAudioManager() {
     audio_thread_.reset(new base::Thread("MockAudioThread"));
@@ -40,7 +44,7 @@ class MockAudioManager : public AudioManagerBase {
       media::AudioDeviceNames* device_names) OVERRIDE {}
   virtual AudioOutputStream* MakeAudioOutputStream(
         const AudioParameters& params) OVERRIDE {
-    return FakeAudioOutputStream::MakeFakeStream(this, params);
+    return media::FakeAudioOutputStream::MakeFakeStream(this, params);
   }
   virtual AudioOutputStream* MakeAudioOutputStreamProxy(
         const AudioParameters& params) OVERRIDE {
@@ -49,7 +53,7 @@ class MockAudioManager : public AudioManagerBase {
   }
   virtual AudioInputStream* MakeAudioInputStream(
         const AudioParameters& params, const std::string& device_id) OVERRIDE {
-    return FakeAudioInputStream::MakeFakeStream(this, params);
+    return media::FakeAudioInputStream::MakeFakeStream(this, params);
   }
   virtual AudioOutputStream* MakeLinearOutputStream(
       const AudioParameters& params) OVERRIDE {
diff --git a/content/common/media/audio_messages.h b/content/common/media/audio_messages.h
index 0acb35c..ce0d4bd 100644
--- a/content/common/media/audio_messages.h
+++ b/content/common/media/audio_messages.h
@@ -23,7 +23,7 @@
 
 IPC_ENUM_TRAITS(AudioStreamState)
 
-IPC_STRUCT_TRAITS_BEGIN(AudioBuffersState)
+IPC_STRUCT_TRAITS_BEGIN(media::AudioBuffersState)
   IPC_STRUCT_TRAITS_MEMBER(pending_bytes)
   IPC_STRUCT_TRAITS_MEMBER(hardware_delay_bytes)
 IPC_STRUCT_TRAITS_END()
@@ -90,12 +90,12 @@ IPC_MESSAGE_CONTROL2(AudioInputMsg_NotifyDeviceStarted,
 // Request that got sent to browser for creating an audio output stream
 IPC_MESSAGE_CONTROL2(AudioHostMsg_CreateStream,
                      int /* stream_id */,
-                     AudioParameters /* params */)
+                     media::AudioParameters /* params */)
 
 // Request that got sent to browser for creating an audio input stream
 IPC_MESSAGE_CONTROL4(AudioInputHostMsg_CreateStream,
                      int /* stream_id */,
-                     AudioParameters /* params */,
+                     media::AudioParameters /* params */,
                      std::string /* device_id */,
                      bool /* automatic_gain_control */)
 
diff --git a/content/common/media/audio_param_traits.cc b/content/common/media/audio_param_traits.cc
index 049037f..7092540 100644
--- a/content/common/media/audio_param_traits.cc
+++ b/content/common/media/audio_param_traits.cc
@@ -7,6 +7,8 @@
 #include "base/stringprintf.h"
 #include "media/audio/audio_parameters.h"
 
+using media::AudioParameters;
+
 namespace IPC {
 
 void ParamTraits<AudioParameters>::Write(Message* m,
diff --git a/content/common/media/audio_param_traits.h b/content/common/media/audio_param_traits.h
index 13c1139..578f9a3 100644
--- a/content/common/media/audio_param_traits.h
+++ b/content/common/media/audio_param_traits.h
@@ -9,13 +9,15 @@
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_param_traits.h"
 
+namespace media {
 class AudioParameters;
+}
 
 namespace IPC {
 
 template <>
-struct ParamTraits<AudioParameters> {
-  typedef AudioParameters param_type;
+struct ParamTraits<media::AudioParameters> {
+  typedef media::AudioParameters param_type;
   static void Write(Message* m, const param_type& p);
   static bool Read(const Message* m, PickleIterator* iter, param_type* r);
   static void Log(const param_type& p, std::string* l);
diff --git a/content/renderer/media/audio_device.cc b/content/renderer/media/audio_device.cc
index b1e5cdf..60e36a7 100644
--- a/content/renderer/media/audio_device.cc
+++ b/content/renderer/media/audio_device.cc
@@ -23,7 +23,7 @@ using media::AudioRendererSink;
 class AudioDevice::AudioThreadCallback
     : public AudioDeviceThread::Callback {
  public:
-  AudioThreadCallback(const AudioParameters& audio_parameters,
+  AudioThreadCallback(const media::AudioParameters& audio_parameters,
                       base::SharedMemoryHandle memory,
                       int memory_length,
                       AudioRendererSink::RenderCallback* render_callback);
@@ -49,7 +49,7 @@ AudioDevice::AudioDevice()
   filter_ = RenderThreadImpl::current()->audio_message_filter();
 }
 
-AudioDevice::AudioDevice(const AudioParameters& params,
+AudioDevice::AudioDevice(const media::AudioParameters& params,
                          RenderCallback* callback)
     : ScopedLoopObserver(ChildProcess::current()->io_message_loop()),
       audio_parameters_(params),
@@ -61,7 +61,7 @@ AudioDevice::AudioDevice(const AudioParameters& params,
   filter_ = RenderThreadImpl::current()->audio_message_filter();
 }
 
-void AudioDevice::Initialize(const AudioParameters& params,
+void AudioDevice::Initialize(const media::AudioParameters& params,
                              RenderCallback* callback) {
   CHECK_EQ(0, stream_id_) <<
       "AudioDevice::Initialize() must be called before Start()";
@@ -130,7 +130,7 @@ void AudioDevice::GetVolume(double* volume) {
   *volume = volume_;
 }
 
-void AudioDevice::InitializeOnIOThread(const AudioParameters& params) {
+void AudioDevice::InitializeOnIOThread(const media::AudioParameters& params) {
   DCHECK(message_loop()->BelongsToCurrentThread());
   // Make sure we don't create the stream more than once.
   DCHECK_EQ(0, stream_id_);
@@ -262,7 +262,7 @@ void AudioDevice::WillDestroyCurrentMessageLoop() {
 // AudioDevice::AudioThreadCallback
 
 AudioDevice::AudioThreadCallback::AudioThreadCallback(
-    const AudioParameters& audio_parameters,
+    const media::AudioParameters& audio_parameters,
     base::SharedMemoryHandle memory,
     int memory_length,
     media::AudioRendererSink::RenderCallback* render_callback)
diff --git a/content/renderer/media/audio_device.h b/content/renderer/media/audio_device.h
index 4cdb946..9410ce7 100644
--- a/content/renderer/media/audio_device.h
+++ b/content/renderer/media/audio_device.h
@@ -76,6 +76,10 @@
 #include "media/audio/audio_parameters.h"
 #include "media/base/audio_renderer_sink.h"
 
+namespace media {
+class AudioParameters;
+}
+
 class CONTENT_EXPORT AudioDevice
     : NON_EXPORTED_BASE(public media::AudioRendererSink),
       public AudioMessageFilter::Delegate,
@@ -86,11 +90,11 @@ class CONTENT_EXPORT AudioDevice
   // Minimal constructor where Initialize() must be called later.
   AudioDevice();
 
-  AudioDevice(const AudioParameters& params, RenderCallback* callback);
+  AudioDevice(const media::AudioParameters& params, RenderCallback* callback);
 
   // AudioRendererSink implementation.
 
-  virtual void Initialize(const AudioParameters& params,
+  virtual void Initialize(const media::AudioParameters& params,
                           RenderCallback* callback) OVERRIDE;
   // Starts audio playback.
   virtual void Start() OVERRIDE;
@@ -132,7 +136,7 @@ class CONTENT_EXPORT AudioDevice
   // The following methods are tasks posted on the IO thread that needs to
   // be executed on that thread. They interact with AudioMessageFilter and
   // sends IPC messages on that thread.
-  void InitializeOnIOThread(const AudioParameters& params);
+  void InitializeOnIOThread(const media::AudioParameters& params);
   void PlayOnIOThread();
   void PauseOnIOThread(bool flush);
   void ShutDownOnIOThread();
@@ -144,7 +148,7 @@ class CONTENT_EXPORT AudioDevice
   // If the IO loop dies before we do, we shut down the audio thread from here.
   virtual void WillDestroyCurrentMessageLoop() OVERRIDE;
 
-  AudioParameters audio_parameters_;
+  media::AudioParameters audio_parameters_;
 
   RenderCallback* callback_;
 
diff --git a/content/renderer/media/audio_device_thread.cc b/content/renderer/media/audio_device_thread.cc
index 77f37dcf..c3cb6ce 100644
--- a/content/renderer/media/audio_device_thread.cc
+++ b/content/renderer/media/audio_device_thread.cc
@@ -170,9 +170,9 @@ void AudioDeviceThread::Thread::Run() {
 
 // AudioDeviceThread::Callback implementation
 
-AudioDeviceThread::Callback::Callback(const AudioParameters& audio_parameters,
-                                      base::SharedMemoryHandle memory,
-                                      int memory_length)
+AudioDeviceThread::Callback::Callback(
+    const media::AudioParameters& audio_parameters,
+    base::SharedMemoryHandle memory, int memory_length)
     : audio_parameters_(audio_parameters),
       samples_per_ms_(audio_parameters.sample_rate() / 1000),
       bytes_per_ms_(audio_parameters.channels() *
diff --git a/content/renderer/media/audio_device_thread.h b/content/renderer/media/audio_device_thread.h
index 51c6fda..0b9f82e 100644
--- a/content/renderer/media/audio_device_thread.h
+++ b/content/renderer/media/audio_device_thread.h
@@ -35,7 +35,7 @@ class CONTENT_EXPORT AudioDeviceThread {
   // AudioDevice thread.
   class Callback {
    public:
-    Callback(const AudioParameters& audio_parameters,
+    Callback(const media::AudioParameters& audio_parameters,
              base::SharedMemoryHandle memory,
              int memory_length);
     virtual ~Callback();
@@ -54,7 +54,7 @@ class CONTENT_EXPORT AudioDeviceThread {
     // Protected so that derived classes can access directly.
     // The variables are 'const' since values are calculated/set in the
     // constructor and must never change.
-    const AudioParameters audio_parameters_;
+    const media::AudioParameters audio_parameters_;
     const int samples_per_ms_;
     const int bytes_per_ms_;
 
diff --git a/content/renderer/media/audio_input_device.cc b/content/renderer/media/audio_input_device.cc
index 11a3938..09c0ba7 100644
--- a/content/renderer/media/audio_input_device.cc
+++ b/content/renderer/media/audio_input_device.cc
@@ -21,7 +21,7 @@
 class AudioInputDevice::AudioThreadCallback
     : public AudioDeviceThread::Callback {
  public:
-  AudioThreadCallback(const AudioParameters& audio_parameters,
+  AudioThreadCallback(const media::AudioParameters& audio_parameters,
                       base::SharedMemoryHandle memory,
                       int memory_length,
                       CaptureCallback* capture_callback);
@@ -37,7 +37,7 @@ class AudioInputDevice::AudioThreadCallback
   DISALLOW_COPY_AND_ASSIGN(AudioThreadCallback);
 };
 
-AudioInputDevice::AudioInputDevice(const AudioParameters& params,
+AudioInputDevice::AudioInputDevice(const media::AudioParameters& params,
                                    CaptureCallback* callback,
                                    CaptureEventHandler* event_handler)
     : ScopedLoopObserver(ChildProcess::current()->io_message_loop()),
@@ -117,7 +117,8 @@ void AudioInputDevice::InitializeOnIOThread() {
   // and create the stream when getting a OnDeviceReady() callback.
   if (!session_id_) {
     Send(new AudioInputHostMsg_CreateStream(
-        stream_id_, audio_parameters_, AudioManagerBase::kDefaultDeviceId,
+        stream_id_, audio_parameters_,
+        media::AudioManagerBase::kDefaultDeviceId,
         agc_is_enabled_));
   } else {
     Send(new AudioInputHostMsg_StartDevice(stream_id_, session_id_));
@@ -297,7 +298,7 @@ void AudioInputDevice::WillDestroyCurrentMessageLoop() {
 
 // AudioInputDevice::AudioThreadCallback
 AudioInputDevice::AudioThreadCallback::AudioThreadCallback(
-    const AudioParameters& audio_parameters,
+    const media::AudioParameters& audio_parameters,
     base::SharedMemoryHandle memory,
     int memory_length,
     CaptureCallback* capture_callback)
@@ -316,10 +317,10 @@ void AudioInputDevice::AudioThreadCallback::Process(int pending_data) {
   // The shared memory represents parameters, size of the data buffer and the
   // actual data buffer containing audio data. Map the memory into this
   // structure and parse out parameters and the data area.
-  AudioInputBuffer* buffer =
-      reinterpret_cast<AudioInputBuffer*>(shared_memory_.memory());
+  media::AudioInputBuffer* buffer =
+      reinterpret_cast<media::AudioInputBuffer*>(shared_memory_.memory());
   uint32 size = buffer->params.size;
-  DCHECK_EQ(size, memory_length_ - sizeof(AudioInputBufferParameters));
+  DCHECK_EQ(size, memory_length_ - sizeof(media::AudioInputBufferParameters));
   double volume = buffer->params.volume;
 
   int audio_delay_milliseconds = pending_data / bytes_per_ms_;
diff --git a/content/renderer/media/audio_input_device.h b/content/renderer/media/audio_input_device.h
index 99cd03c..ac68b96 100644
--- a/content/renderer/media/audio_input_device.h
+++ b/content/renderer/media/audio_input_device.h
@@ -118,7 +118,8 @@ class CONTENT_EXPORT AudioInputDevice
   };
 
   // Methods called on main render thread -------------------------------------
-  AudioInputDevice(const AudioParameters& params, CaptureCallback* callback,
+  AudioInputDevice(const media::AudioParameters& params,
+                   CaptureCallback* callback,
                    CaptureEventHandler* event_handler);
   virtual ~AudioInputDevice();
 
@@ -184,7 +185,7 @@ class CONTENT_EXPORT AudioInputDevice
   virtual void WillDestroyCurrentMessageLoop() OVERRIDE;
 
   // Format
-  AudioParameters audio_parameters_;
+  media::AudioParameters audio_parameters_;
 
   CaptureCallback* callback_;
   CaptureEventHandler* event_handler_;
diff --git a/content/renderer/media/audio_renderer_impl.cc b/content/renderer/media/audio_renderer_impl.cc
index 112be63..81d1cc6 100644
--- a/content/renderer/media/audio_renderer_impl.cc
+++ b/content/renderer/media/audio_renderer_impl.cc
@@ -61,7 +61,7 @@ bool AudioRendererImpl::OnInitialize(int bits_per_channel,
   // Please see: http://code.google.com/p/chromium/issues/detail?id=103627
   // for more details.
   audio_parameters_.Reset(
-      AudioParameters::AUDIO_PCM_LINEAR,
+      media::AudioParameters::AUDIO_PCM_LINEAR,
       channel_layout, sample_rate, bits_per_channel,
       audio_hardware::GetHighLatencyOutputBufferSize(sample_rate));
 
diff --git a/content/renderer/media/audio_renderer_impl.h b/content/renderer/media/audio_renderer_impl.h
index c2f8864..978f5a0 100644
--- a/content/renderer/media/audio_renderer_impl.h
+++ b/content/renderer/media/audio_renderer_impl.h
@@ -129,7 +129,7 @@ class CONTENT_EXPORT AudioRendererImpl
   // than nothing.
   base::Time earliest_end_time_;
 
-  AudioParameters audio_parameters_;
+  media::AudioParameters audio_parameters_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererImpl);
 };
diff --git a/content/renderer/media/render_audiosourceprovider.cc b/content/renderer/media/render_audiosourceprovider.cc
index 5159d4d..a627bfa 100644
--- a/content/renderer/media/render_audiosourceprovider.cc
+++ b/content/renderer/media/render_audiosourceprovider.cc
@@ -73,7 +73,7 @@ void RenderAudioSourceProvider::GetVolume(double* volume) {
 }
 
 void RenderAudioSourceProvider::Initialize(
-    const AudioParameters& params, RenderCallback* renderer) {
+    const media::AudioParameters& params, RenderCallback* renderer) {
   base::AutoLock auto_lock(sink_lock_);
   CHECK(!is_initialized_);
   renderer_ = renderer;
diff --git a/content/renderer/media/render_audiosourceprovider.h b/content/renderer/media/render_audiosourceprovider.h
index c0a3a88..6d842cb 100644
--- a/content/renderer/media/render_audiosourceprovider.h
+++ b/content/renderer/media/render_audiosourceprovider.h
@@ -60,7 +60,7 @@ class RenderAudioSourceProvider
   virtual bool SetVolume(double volume) OVERRIDE;
   virtual void GetVolume(double* volume) OVERRIDE;
   virtual void Initialize(
-      const AudioParameters& params, RenderCallback* renderer) OVERRIDE;
+      const media::AudioParameters& params, RenderCallback* renderer) OVERRIDE;
 
  private:
   // Set to true when Initialize() is called.
diff --git a/content/renderer/media/renderer_webaudiodevice_impl.cc b/content/renderer/media/renderer_webaudiodevice_impl.cc
index d054325..2a90144 100644
--- a/content/renderer/media/renderer_webaudiodevice_impl.cc
+++ b/content/renderer/media/renderer_webaudiodevice_impl.cc
@@ -8,7 +8,8 @@ using WebKit::WebAudioDevice;
 using WebKit::WebVector;
 
 RendererWebAudioDeviceImpl::RendererWebAudioDeviceImpl(
-    const AudioParameters& params, WebAudioDevice::RenderCallback* callback)
+    const media::AudioParameters& params,
+    WebAudioDevice::RenderCallback* callback)
     : is_running_(false),
       client_callback_(callback) {
   audio_device_ = new AudioDevice(params, this);
diff --git a/content/renderer/media/renderer_webaudiodevice_impl.h b/content/renderer/media/renderer_webaudiodevice_impl.h
index 7b66033..a70c0884 100644
--- a/content/renderer/media/renderer_webaudiodevice_impl.h
+++ b/content/renderer/media/renderer_webaudiodevice_impl.h
@@ -12,12 +12,15 @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebAudioDevice.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebVector.h"
 
+namespace media {
 class AudioParameters;
+}
 
-class RendererWebAudioDeviceImpl : public WebKit::WebAudioDevice,
-                                   public AudioDevice::RenderCallback {
+class RendererWebAudioDeviceImpl
+    : public WebKit::WebAudioDevice,
+      public AudioDevice::RenderCallback {
  public:
-  RendererWebAudioDeviceImpl(const AudioParameters& params,
+  RendererWebAudioDeviceImpl(const media::AudioParameters& params,
                              WebKit::WebAudioDevice::RenderCallback* callback);
   virtual ~RendererWebAudioDeviceImpl();
 
diff --git a/content/renderer/media/webrtc_audio_device_impl.cc b/content/renderer/media/webrtc_audio_device_impl.cc
index a25bdca..1eeea33 100644
--- a/content/renderer/media/webrtc_audio_device_impl.cc
+++ b/content/renderer/media/webrtc_audio_device_impl.cc
@@ -11,6 +11,8 @@
 #include "content/renderer/render_thread_impl.h"
 #include "media/audio/audio_util.h"
 
+using media::AudioParameters;
+
 static const int64 kMillisecondsBetweenProcessCalls = 5000;
 static const double kMaxVolumeLevel = 255.0;
 
diff --git a/content/renderer/media/webrtc_audio_device_impl.h b/content/renderer/media/webrtc_audio_device_impl.h
index c00e129..8900ebf 100644
--- a/content/renderer/media/webrtc_audio_device_impl.h
+++ b/content/renderer/media/webrtc_audio_device_impl.h
@@ -416,8 +416,8 @@ class CONTENT_EXPORT WebRtcAudioDeviceImpl
   webrtc::AudioTransport* audio_transport_callback_;
 
   // Cached values of utilized audio parameters. Platform dependent.
-  AudioParameters input_audio_parameters_;
-  AudioParameters output_audio_parameters_;
+  media::AudioParameters input_audio_parameters_;
+  media::AudioParameters output_audio_parameters_;
 
   // Cached value of the current audio delay on the input/capture side.
   int input_delay_ms_;
diff --git a/content/renderer/pepper/pepper_platform_audio_input_impl.cc b/content/renderer/pepper/pepper_platform_audio_input_impl.cc
index 6c42f75..3ac06f2 100644
--- a/content/renderer/pepper/pepper_platform_audio_input_impl.cc
+++ b/content/renderer/pepper/pepper_platform_audio_input_impl.cc
@@ -93,7 +93,7 @@ bool PepperPlatformAudioInputImpl::Initialize(
   plugin_delegate_ = plugin_delegate;
   client_ = client;
 
-  params_.Reset(AudioParameters::AUDIO_PCM_LINEAR, CHANNEL_LAYOUT_MONO,
+  params_.Reset(media::AudioParameters::AUDIO_PCM_LINEAR, CHANNEL_LAYOUT_MONO,
                 sample_rate, 16, frames_per_buffer);
 
   if (device_id.empty()) {
@@ -127,7 +127,8 @@ void PepperPlatformAudioInputImpl::InitializeOnIOThread(int session_id) {
   if (!session_id) {
     // We will be notified by OnStreamCreated().
     filter_->Send(new AudioInputHostMsg_CreateStream(
-        stream_id_, params_, AudioManagerBase::kDefaultDeviceId, false));
+        stream_id_, params_,
+        media::AudioManagerBase::kDefaultDeviceId, false));
   } else {
     // We will be notified by OnDeviceReady().
     filter_->Send(new AudioInputHostMsg_StartDevice(stream_id_, session_id));
diff --git a/content/renderer/pepper/pepper_platform_audio_input_impl.h b/content/renderer/pepper/pepper_platform_audio_input_impl.h
index 15681bb..384a7c6 100644
--- a/content/renderer/pepper/pepper_platform_audio_input_impl.h
+++ b/content/renderer/pepper/pepper_platform_audio_input_impl.h
@@ -15,7 +15,10 @@
 #include "media/audio/audio_parameters.h"
 #include "webkit/plugins/ppapi/plugin_delegate.h"
 
+namespace media {
 class AudioParameters;
+}
+
 class PepperPluginDelegateImpl;
 
 // PepperPlatformAudioInputImpl is operated on two threads: the main thread (the
@@ -25,6 +28,7 @@ class PepperPluginDelegateImpl;
 // also sent on the main thread. Internally, this class sends audio input IPC
 // messages and receives AudioInputMessageFilter::Delegate notifications on the
 // I/O thread.
+
 class PepperPlatformAudioInputImpl
     : public webkit::ppapi::PluginDelegate::PlatformAudioInput,
       public AudioInputMessageFilter::Delegate,
@@ -102,7 +106,7 @@ class PepperPlatformAudioInputImpl
   bool shutdown_called_;
 
   // Initialized on the main thread and accessed on the I/O thread afterwards.
-  AudioParameters params_;
+  media::AudioParameters params_;
 
   DISALLOW_COPY_AND_ASSIGN(PepperPlatformAudioInputImpl);
 };
diff --git a/content/renderer/pepper/pepper_platform_audio_output_impl.cc b/content/renderer/pepper/pepper_platform_audio_output_impl.cc
index be636dc..bab8322 100644
--- a/content/renderer/pepper/pepper_platform_audio_output_impl.cc
+++ b/content/renderer/pepper/pepper_platform_audio_output_impl.cc
@@ -83,20 +83,20 @@ bool PepperPlatformAudioOutputImpl::Initialize(
 
   client_ = client;
 
-  AudioParameters::Format format;
+  media::AudioParameters::Format format;
   const int kMaxFramesForLowLatency = 2048;
   // Use the low latency back end if the client request is compatible, and
   // the sample count is low enough to justify using AUDIO_PCM_LOW_LATENCY.
   if (sample_rate == audio_hardware::GetOutputSampleRate() &&
       frames_per_buffer <= kMaxFramesForLowLatency &&
       frames_per_buffer % audio_hardware::GetOutputBufferSize() == 0) {
-    format = AudioParameters::AUDIO_PCM_LOW_LATENCY;
+    format = media::AudioParameters::AUDIO_PCM_LOW_LATENCY;
   } else {
-    format = AudioParameters::AUDIO_PCM_LINEAR;
+    format = media::AudioParameters::AUDIO_PCM_LINEAR;
   }
 
-  AudioParameters params(format, CHANNEL_LAYOUT_STEREO, sample_rate,
-                         16, frames_per_buffer);
+  media::AudioParameters params(format, CHANNEL_LAYOUT_STEREO, sample_rate, 16,
+                                frames_per_buffer);
 
   ChildProcess::current()->io_message_loop()->PostTask(
       FROM_HERE,
@@ -106,7 +106,7 @@ bool PepperPlatformAudioOutputImpl::Initialize(
 }
 
 void PepperPlatformAudioOutputImpl::InitializeOnIOThread(
-    const AudioParameters& params) {
+    const media::AudioParameters& params) {
   stream_id_ = filter_->AddDelegate(this);
   filter_->Send(new AudioHostMsg_CreateStream(stream_id_, params));
 }
diff --git a/content/renderer/pepper/pepper_platform_audio_output_impl.h b/content/renderer/pepper/pepper_platform_audio_output_impl.h
index f1d5cba..b1609ef 100644
--- a/content/renderer/pepper/pepper_platform_audio_output_impl.h
+++ b/content/renderer/pepper/pepper_platform_audio_output_impl.h
@@ -10,7 +10,9 @@
 #include "content/renderer/media/audio_message_filter.h"
 #include "webkit/plugins/ppapi/plugin_delegate.h"
 
+namespace media{
 class AudioParameters;
+}
 
 namespace base {
 class MessageLoopProxy;
@@ -44,7 +46,7 @@ class PepperPlatformAudioOutputImpl
       webkit::ppapi::PluginDelegate::PlatformAudioOutputClient* client);
 
   // I/O thread backends to above functions.
-  void InitializeOnIOThread(const AudioParameters& params);
+  void InitializeOnIOThread(const media::AudioParameters& params);
   void StartPlaybackOnIOThread();
   void StopPlaybackOnIOThread();
   void ShutDownOnIOThread();
diff --git a/content/renderer/renderer_webkitplatformsupport_impl.cc b/content/renderer/renderer_webkitplatformsupport_impl.cc
index 18c2008..7afb22d 100644
--- a/content/renderer/renderer_webkitplatformsupport_impl.cc
+++ b/content/renderer/renderer_webkitplatformsupport_impl.cc
@@ -658,11 +658,9 @@ RendererWebKitPlatformSupportImpl::createAudioDevice(
       layout = CHANNEL_LAYOUT_STEREO;
   }
 
-  AudioParameters params(AudioParameters::AUDIO_PCM_LOW_LATENCY,
-                         layout,
-                         static_cast<int>(sampleRate),
-                         16,
-                         bufferSize);
+  media::AudioParameters params(
+      media::AudioParameters::AUDIO_PCM_LOW_LATENCY, layout,
+      static_cast<int>(sampleRate), 16, bufferSize);
 
   return new RendererWebAudioDeviceImpl(params, callback);
 }
diff --git a/content/test/webrtc_audio_device_test.cc b/content/test/webrtc_audio_device_test.cc
index cb37584..0f11917 100644
--- a/content/test/webrtc_audio_device_test.cc
+++ b/content/test/webrtc_audio_device_test.cc
@@ -164,7 +164,7 @@ void WebRTCAudioDeviceTest::InitializeIOThread(const char* thread_name) {
   io_thread_.reset(new content::TestBrowserThread(content::BrowserThread::IO,
                                                   MessageLoop::current()));
 
-  audio_manager_.reset(AudioManager::Create());
+  audio_manager_.reset(media::AudioManager::Create());
 
   // Populate our resource context.
   test_request_context_ = new TestURLRequestContext();
@@ -221,7 +221,7 @@ void WebRTCAudioDeviceTest::OnGetHardwareInputSampleRate(int* sample_rate) {
   EXPECT_TRUE(audio_util_callback_);
   *sample_rate = audio_util_callback_ ?
       audio_util_callback_->GetAudioInputHardwareSampleRate(
-          AudioManagerBase::kDefaultDeviceId) : 0;
+          media::AudioManagerBase::kDefaultDeviceId) : 0;
 }
 
 void WebRTCAudioDeviceTest::OnGetHardwareInputChannelLayout(
@@ -229,7 +229,7 @@ void WebRTCAudioDeviceTest::OnGetHardwareInputChannelLayout(
   EXPECT_TRUE(audio_util_callback_);
   *layout = audio_util_callback_ ?
       audio_util_callback_->GetAudioInputHardwareChannelLayout(
-          AudioManagerBase::kDefaultDeviceId) : CHANNEL_LAYOUT_NONE;
+          media::AudioManagerBase::kDefaultDeviceId) : CHANNEL_LAYOUT_NONE;
 }
 
 // IPC::Channel::Listener implementation.
diff --git a/content/test/webrtc_audio_device_test.h b/content/test/webrtc_audio_device_test.h
index bd82c87..dfe9f27 100644
--- a/content/test/webrtc_audio_device_test.h
+++ b/content/test/webrtc_audio_device_test.h
@@ -20,7 +20,6 @@
 #include "third_party/webrtc/common_types.h"
 
 class AudioInputRendererHost;
-class AudioManager;
 class AudioRendererHost;
 class RenderThreadImpl;
 class WebRTCMockRenderProcess;
@@ -38,6 +37,10 @@ class ResourceContext;
 class TestBrowserThread;
 }
 
+namespace media {
+class AudioManager;
+}
+
 namespace media_stream {
 class MediaStreamManager;
 }
@@ -166,7 +169,7 @@ class WebRTCAudioDeviceTest
   scoped_ptr<WebRTCMockRenderProcess> mock_process_;
   scoped_ptr<MockMediaObserver> media_observer_;
   scoped_ptr<media_stream::MediaStreamManager> media_stream_manager_;
-  scoped_ptr<AudioManager> audio_manager_;
+  scoped_ptr<media::AudioManager> audio_manager_;
   scoped_ptr<content::MockResourceContext> resource_context_;
   scoped_refptr<net::URLRequestContext> test_request_context_;
   scoped_ptr<IPC::Channel> channel_;
diff --git a/media/audio/android/audio_manager_android.cc b/media/audio/android/audio_manager_android.cc
index 04a0564..9feb5c7 100644
--- a/media/audio/android/audio_manager_android.cc
+++ b/media/audio/android/audio_manager_android.cc
@@ -11,6 +11,8 @@
 #include "media/audio/audio_manager.h"
 #include "media/audio/fake_audio_input_stream.h"
 
+namespace media {
+
 // Maximum number of output streams that can be open simultaneously.
 static const int kMaxOutputStreams = 10;
 
@@ -65,3 +67,5 @@ AudioInputStream* AudioManagerAndroid::MakeLowLatencyInputStream(
   DCHECK_EQ(AudioParameters::AUDIO_PCM_LOW_LATENCY, params.format());
   return new OpenSLESInputStream(this, params);
 }
+
+}  // namespace media
diff --git a/media/audio/android/audio_manager_android.h b/media/audio/android/audio_manager_android.h
index 5d42270..90e319a 100644
--- a/media/audio/android/audio_manager_android.h
+++ b/media/audio/android/audio_manager_android.h
@@ -7,6 +7,8 @@
 
 #include "media/audio/audio_manager_base.h"
 
+namespace media {
+
 // Android implemention of AudioManager.
 class AudioManagerAndroid : public AudioManagerBase {
  public:
@@ -35,4 +37,6 @@ class AudioManagerAndroid : public AudioManagerBase {
   DISALLOW_COPY_AND_ASSIGN(AudioManagerAndroid);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_ANDROID_AUDIO_MANAGER_ANDROID_H_
diff --git a/media/audio/android/audio_track_output_android.cc b/media/audio/android/audio_track_output_android.cc
index d65ff19..7342750 100644
--- a/media/audio/android/audio_track_output_android.cc
+++ b/media/audio/android/audio_track_output_android.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -12,6 +12,8 @@
 using base::android::AttachCurrentThread;
 using base::android::CheckException;
 
+namespace media {
+
 static const int kTimerIntervalInMilliseconds = 50;
 
 class AudioTrackOutputStream::StreamBuffer {
@@ -309,3 +311,5 @@ void AudioTrackOutputStream::FillAudioBufferTask() {
   CheckException(env);
   env->DeleteLocalRef(buf);
 }
+
+}  // namespace media
diff --git a/media/audio/android/audio_track_output_android.h b/media/audio/android/audio_track_output_android.h
index ddeab43..0ab7647 100644
--- a/media/audio/android/audio_track_output_android.h
+++ b/media/audio/android/audio_track_output_android.h
@@ -14,6 +14,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerAndroid;
 
 // Implements PCM audio output support for Android using the AudioTrack API.
@@ -68,4 +70,6 @@ class AudioTrackOutputStream : public AudioOutputStream {
   DISALLOW_COPY_AND_ASSIGN(AudioTrackOutputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_ANDROID_AUDIO_TRACK_OUTPUT_ANDROID_H_
diff --git a/media/audio/android/audio_track_output_stub_android.cc b/media/audio/android/audio_track_output_stub_android.cc
index 5171591..ab4f9ba 100644
--- a/media/audio/android/audio_track_output_stub_android.cc
+++ b/media/audio/android/audio_track_output_stub_android.cc
@@ -1,9 +1,11 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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 "media/audio/android/audio_track_output_android.h"
 
+namespace media {
+
 // This file was added because there is no Java environment in
 // upstream yet, audio_track_output_android.cc should be used in
 // downstream.
@@ -14,3 +16,5 @@ AudioOutputStream* AudioTrackOutputStream::MakeStream(
     const AudioParameters& params) {
   return NULL;
 }
+
+}  // namespace media
diff --git a/media/audio/audio_buffers_state.cc b/media/audio/audio_buffers_state.cc
index 7e829fe..6c4f950 100644
--- a/media/audio/audio_buffers_state.cc
+++ b/media/audio/audio_buffers_state.cc
@@ -4,6 +4,8 @@
 
 #include "media/audio/audio_buffers_state.h"
 
+namespace media {
+
 AudioBuffersState::AudioBuffersState()
     : pending_bytes(0),
       hardware_delay_bytes(0) {
@@ -14,3 +16,5 @@ AudioBuffersState::AudioBuffersState(int pending_bytes,
     : pending_bytes(pending_bytes),
       hardware_delay_bytes(hardware_delay_bytes) {
 }
+
+}  // namespace media
diff --git a/media/audio/audio_buffers_state.h b/media/audio/audio_buffers_state.h
index a7299e1..79244ae 100644
--- a/media/audio/audio_buffers_state.h
+++ b/media/audio/audio_buffers_state.h
@@ -7,6 +7,8 @@
 
 #include "media/base/media_export.h"
 
+namespace media {
+
 // AudioBuffersState struct stores current state of audio buffers.
 // It is used for audio synchronization.
 struct MEDIA_EXPORT AudioBuffersState {
@@ -25,4 +27,6 @@ struct MEDIA_EXPORT AudioBuffersState {
   int hardware_delay_bytes;
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_AUDIO_BUFFERS_STATE_H_
diff --git a/media/audio/audio_input_device_unittest.cc b/media/audio/audio_input_device_unittest.cc
index 470dbab..c0a4dde 100644
--- a/media/audio/audio_input_device_unittest.cc
+++ b/media/audio/audio_input_device_unittest.cc
@@ -15,7 +15,8 @@
 #endif
 
 using base::win::ScopedCOMInitializer;
-using media::AudioDeviceNames;
+
+namespace media {
 
 // Test fixture which allows us to override the default enumeration API on
 // Windows.
@@ -171,3 +172,5 @@ TEST_F(AudioInputDeviceTest, ConvertToWinXPDeviceId) {
 }
 
 #endif
+
+}  // namespace media
diff --git a/media/audio/audio_input_stream_impl.cc b/media/audio/audio_input_stream_impl.cc
index 529a9c4..f68317c 100644
--- a/media/audio/audio_input_stream_impl.cc
+++ b/media/audio/audio_input_stream_impl.cc
@@ -5,6 +5,8 @@
 #include "base/logging.h"
 #include "media/audio/audio_input_stream_impl.h"
 
+namespace media {
+
 static const int kMinIntervalBetweenVolumeUpdatesMs = 1000;
 
 AudioInputStreamImpl::AudioInputStreamImpl()
@@ -66,3 +68,4 @@ void AudioInputStreamImpl::GetNormalizedVolume() {
   }
 }
 
+}  // namespace media
diff --git a/media/audio/audio_input_stream_impl.h b/media/audio/audio_input_stream_impl.h
index d223985..64980a9 100644
--- a/media/audio/audio_input_stream_impl.h
+++ b/media/audio/audio_input_stream_impl.h
@@ -10,6 +10,8 @@
 #include "base/time.h"
 #include "media/audio/audio_io.h"
 
+namespace media {
+
 // AudioInputStreamImpl implements platform-independent parts of the
 // AudioInputStream interface. Each platform dependent implementation
 // should derive from this class.
@@ -64,4 +66,6 @@ class MEDIA_EXPORT AudioInputStreamImpl : public AudioInputStream {
   DISALLOW_COPY_AND_ASSIGN(AudioInputStreamImpl);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_AUDIO_INPUT_STREAM_IMPL_H_
diff --git a/media/audio/audio_input_unittest.cc b/media/audio/audio_input_unittest.cc
index 8d7b2ac..ee7d6d8 100644
--- a/media/audio/audio_input_unittest.cc
+++ b/media/audio/audio_input_unittest.cc
@@ -11,6 +11,8 @@
 #include "media/audio/audio_manager_base.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+namespace media {
+
 static const int kSamplingRate = 8000;
 static const int kSamplesPerPacket = kSamplingRate / 20;
 
@@ -170,3 +172,5 @@ TEST(AudioInputTest, Record) {
   ais->Stop();
   ais->Close();
 }
+
+}  // namespace media
diff --git a/media/audio/audio_input_volume_unittest.cc b/media/audio/audio_input_volume_unittest.cc
index 99f4e83..c49187e 100644
--- a/media/audio/audio_input_volume_unittest.cc
+++ b/media/audio/audio_input_volume_unittest.cc
@@ -12,7 +12,8 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 using base::win::ScopedCOMInitializer;
-using media::AudioDeviceNames;
+
+namespace media {
 
 class AudioInputVolumeTest : public ::testing::Test {
  protected:
@@ -157,3 +158,5 @@ TEST_F(AudioInputVolumeTest, InputVolumeTest) {
     ais->Close();
   }
 }
+
+}  // namespace media
diff --git a/media/audio/audio_io.h b/media/audio/audio_io.h
index 489e0ab..cb83576 100644
--- a/media/audio/audio_io.h
+++ b/media/audio/audio_io.h
@@ -45,6 +45,9 @@
 // as the data is written to the audio device. Size of each packet is determined
 // by |samples_per_packet| specified in AudioParameters  when the stream is
 // created.
+
+namespace media {
+
 class MEDIA_EXPORT AudioOutputStream {
  public:
   // Audio sources must implement AudioSourceCallback. This interface will be
@@ -173,4 +176,6 @@ class MEDIA_EXPORT AudioInputStream {
   virtual bool GetAutomaticGainControl() = 0;
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_AUDIO_IO_H_
diff --git a/media/audio/audio_low_latency_input_output_unittest.cc b/media/audio/audio_low_latency_input_output_unittest.cc
index 7064063..8d501ca 100644
--- a/media/audio/audio_low_latency_input_output_unittest.cc
+++ b/media/audio/audio_low_latency_input_output_unittest.cc
@@ -29,6 +29,10 @@
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+using base::win::ScopedCOMInitializer;
+
+namespace media {
+
 #if defined(OS_LINUX) || defined(OS_OPENBSD)
 typedef AudioManagerLinux AudioManagerAnyPlatform;
 #elif defined(OS_MACOSX)
@@ -39,9 +43,6 @@ typedef AudioManagerWin AudioManagerAnyPlatform;
 typedef AudioManagerAndroid AudioManagerAnyPlatform;
 #endif
 
-using base::win::ScopedCOMInitializer;
-
-namespace {
 // Limits the number of delay measurements we can store in an array and
 // then write to file at end of the WASAPIAudioInputOutputFullDuplex test.
 static const size_t kMaxDelayMeasurements = 1000;
@@ -122,8 +123,6 @@ class AudioLowLatencyInputOutputTest : public testing::Test {
   DISALLOW_COPY_AND_ASSIGN(AudioLowLatencyInputOutputTest);
 };
 
-}  // namespace
-
 // This audio source/sink implementation should be used for manual tests
 // only since delay measurements are stored on an output text file.
 // All incoming/recorded audio packets are stored in an intermediate media
@@ -463,3 +462,5 @@ TEST_F(AudioLowLatencyInputOutputTest, DISABLED_FullDuplexDelayMeasurement) {
   aos->Close();
   ais->Close();
 }
+
+}  // namespace media
diff --git a/media/audio/audio_manager.cc b/media/audio/audio_manager.cc
index d118789..028b409 100644
--- a/media/audio/audio_manager.cc
+++ b/media/audio/audio_manager.cc
@@ -8,6 +8,8 @@
 #include "base/logging.h"
 #include "base/message_loop.h"
 
+namespace media {
+
 // Forward declaration of the platform specific AudioManager factory function.
 AudioManager* CreateAudioManager();
 
@@ -23,3 +25,5 @@ AudioManager* AudioManager::Create() {
   ret->Init();
   return ret;
 }
+
+}  // namespace media
diff --git a/media/audio/audio_manager.h b/media/audio/audio_manager.h
index e1f0145..704d48f 100644
--- a/media/audio/audio_manager.h
+++ b/media/audio/audio_manager.h
@@ -13,13 +13,17 @@
 #include "media/audio/audio_device_name.h"
 #include "media/audio/audio_parameters.h"
 
-class AudioInputStream;
-class AudioOutputStream;
 class MessageLoop;
+
 namespace base {
 class MessageLoopProxy;
 }
 
+namespace media {
+
+class AudioInputStream;
+class AudioOutputStream;
+
 // Manages all audio resources. In particular it owns the AudioOutputStream
 // objects. Provides some convenience functions that avoid the need to provide
 // iterators over the existing streams.
@@ -57,8 +61,7 @@ class MEDIA_EXPORT AudioManager {
   // Appends a list of available input devices. It is not guaranteed that
   // all the devices in the list support all formats and sample rates for
   // recording.
-  virtual void GetAudioInputDeviceNames(
-      media::AudioDeviceNames* device_names) = 0;
+  virtual void GetAudioInputDeviceNames(AudioDeviceNames* device_names) = 0;
 
   // Factory for all the supported stream formats. |params| defines parameters
   // of the audio stream to be created.
@@ -124,4 +127,6 @@ class MEDIA_EXPORT AudioManager {
   DISALLOW_COPY_AND_ASSIGN(AudioManager);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_AUDIO_MANAGER_H_
diff --git a/media/audio/audio_manager_base.cc b/media/audio/audio_manager_base.cc
index 89191af..45bf0fc 100644
--- a/media/audio/audio_manager_base.cc
+++ b/media/audio/audio_manager_base.cc
@@ -12,6 +12,8 @@
 #include "media/audio/fake_audio_input_stream.h"
 #include "media/audio/fake_audio_output_stream.h"
 
+namespace media {
+
 static const int kStreamCloseDelaySeconds = 5;
 
 // Default maximum number of output streams that can be open simultaneously
@@ -226,3 +228,5 @@ void AudioManagerBase::ShutdownOnAudioThread() {
 
   output_dispatchers_.clear();
 }
+
+}  // namespace media
diff --git a/media/audio/audio_manager_base.h b/media/audio/audio_manager_base.h
index ba27221..acb85b6 100644
--- a/media/audio/audio_manager_base.h
+++ b/media/audio/audio_manager_base.h
@@ -13,12 +13,14 @@
 #include "base/synchronization/lock.h"
 #include "media/audio/audio_manager.h"
 
-class AudioOutputDispatcher;
-
 namespace base {
 class Thread;
 }
 
+namespace media {
+
+class AudioOutputDispatcher;
+
 // AudioManagerBase provides AudioManager functions common for all platforms.
 class MEDIA_EXPORT AudioManagerBase : public AudioManager {
  public:
@@ -124,4 +126,6 @@ class MEDIA_EXPORT AudioManagerBase : public AudioManager {
   DISALLOW_COPY_AND_ASSIGN(AudioManagerBase);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_
diff --git a/media/audio/audio_output_controller_unittest.cc b/media/audio/audio_output_controller_unittest.cc
index cd65f5b..05f3d7f 100644
--- a/media/audio/audio_output_controller_unittest.cc
+++ b/media/audio/audio_output_controller_unittest.cc
@@ -22,6 +22,8 @@ using ::testing::InvokeWithoutArgs;
 using ::testing::NotNull;
 using ::testing::Return;
 
+namespace media {
+
 static const int kSampleRate = AudioParameters::kAudioCDSampleRate;
 static const int kBitsPerSample = 16;
 static const ChannelLayout kChannelLayout = CHANNEL_LAYOUT_STEREO;
@@ -29,8 +31,6 @@ static const int kSamplesPerPacket = kSampleRate / 10;
 static const int kHardwareBufferSize = kSamplesPerPacket *
     ChannelLayoutToChannelCount(kChannelLayout) * kBitsPerSample / 8;
 
-namespace media {
-
 class MockAudioOutputControllerEventHandler
     : public AudioOutputController::EventHandler {
  public:
diff --git a/media/audio/audio_output_dispatcher.cc b/media/audio/audio_output_dispatcher.cc
index 1ac7e8a..998fc1b 100644
--- a/media/audio/audio_output_dispatcher.cc
+++ b/media/audio/audio_output_dispatcher.cc
@@ -10,6 +10,8 @@
 #include "base/time.h"
 #include "media/audio/audio_io.h"
 
+namespace media {
+
 AudioOutputDispatcher::AudioOutputDispatcher(
     AudioManager* audio_manager, const AudioParameters& params,
     base::TimeDelta close_delay)
@@ -168,3 +170,5 @@ void AudioOutputDispatcher::ClosePendingStreams() {
     idle_streams_.pop_back();
   }
 }
+
+}  // namespace media
diff --git a/media/audio/audio_output_dispatcher.h b/media/audio/audio_output_dispatcher.h
index cf01a31..79474a4 100644
--- a/media/audio/audio_output_dispatcher.h
+++ b/media/audio/audio_output_dispatcher.h
@@ -32,9 +32,12 @@
 #include "media/audio/audio_manager.h"
 #include "media/audio/audio_parameters.h"
 
-class AudioOutputStream;
 class MessageLoop;
 
+namespace media {
+
+class AudioOutputStream;
+
 class MEDIA_EXPORT AudioOutputDispatcher
     : public base::RefCountedThreadSafe<AudioOutputDispatcher> {
  public:
@@ -107,4 +110,6 @@ class MEDIA_EXPORT AudioOutputDispatcher
   DISALLOW_COPY_AND_ASSIGN(AudioOutputDispatcher);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_AUDIO_OUTPUT_DISPATCHER_H_
diff --git a/media/audio/audio_output_proxy.cc b/media/audio/audio_output_proxy.cc
index 29490db..b1d65ba 100644
--- a/media/audio/audio_output_proxy.cc
+++ b/media/audio/audio_output_proxy.cc
@@ -9,6 +9,8 @@
 #include "media/audio/audio_manager.h"
 #include "media/audio/audio_output_dispatcher.h"
 
+namespace media {
+
 AudioOutputProxy::AudioOutputProxy(AudioOutputDispatcher* dispatcher)
     : dispatcher_(dispatcher),
       state_(kCreated),
@@ -93,3 +95,5 @@ void AudioOutputProxy::Close() {
   // dispatcher+audio manager.
   delete this;
 }
+
+}  // namespace media
diff --git a/media/audio/audio_output_proxy.h b/media/audio/audio_output_proxy.h
index 8e1b350..d34f81f 100644
--- a/media/audio/audio_output_proxy.h
+++ b/media/audio/audio_output_proxy.h
@@ -12,6 +12,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioOutputDispatcher;
 
 // AudioOutputProxy is an audio otput stream that uses resources more
@@ -62,4 +64,6 @@ class MEDIA_EXPORT AudioOutputProxy
   DISALLOW_COPY_AND_ASSIGN(AudioOutputProxy);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_AUDIO_OUTPUT_PROXY_H_
diff --git a/media/audio/audio_output_proxy_unittest.cc b/media/audio/audio_output_proxy_unittest.cc
index 1f955b6..3dbfd2f2 100644
--- a/media/audio/audio_output_proxy_unittest.cc
+++ b/media/audio/audio_output_proxy_unittest.cc
@@ -14,6 +14,15 @@
 using ::testing::_;
 using ::testing::Mock;
 using ::testing::Return;
+using media::AudioBuffersState;
+using media::AudioInputStream;
+using media::AudioManager;
+using media::AudioOutputDispatcher;
+using media::AudioOutputProxy;
+using media::AudioOutputStream;
+using media::AudioParameters;
+
+namespace {
 
 static const int kTestCloseDelayMs = 100;
 
@@ -65,6 +74,10 @@ class MockAudioSourceCallback : public AudioOutputStream::AudioSourceCallback {
   MOCK_METHOD2(OnError, void(AudioOutputStream* stream, int code));
 };
 
+}  // namespace
+
+namespace media {
+
 class AudioOutputProxyTest : public testing::Test {
  protected:
   virtual void SetUp() {
@@ -371,3 +384,5 @@ TEST_F(AudioOutputProxyTest, StartFailed) {
 
   proxy->Close();
 }
+
+}  // namespace media
diff --git a/media/audio/audio_parameters.cc b/media/audio/audio_parameters.cc
index 852bd12..fb9b6f2 100644
--- a/media/audio/audio_parameters.cc
+++ b/media/audio/audio_parameters.cc
@@ -6,6 +6,8 @@
 
 #include "media/base/limits.h"
 
+namespace media {
+
 AudioParameters::AudioParameters()
     : format_(AUDIO_PCM_LINEAR),
       channel_layout_(CHANNEL_LAYOUT_NONE),
@@ -81,3 +83,5 @@ bool AudioParameters::Compare::operator()(
     return false;
   return a.frames_per_buffer_ < b.frames_per_buffer_;
 }
+
+}  // namespace media
diff --git a/media/audio/audio_parameters.h b/media/audio/audio_parameters.h
index 392d328..8ce2070 100644
--- a/media/audio/audio_parameters.h
+++ b/media/audio/audio_parameters.h
@@ -9,6 +9,8 @@
 #include "media/base/channel_layout.h"
 #include "media/base/media_export.h"
 
+namespace media {
+
 struct MEDIA_EXPORT AudioInputBufferParameters {
   double volume;
   uint32 size;
@@ -83,4 +85,6 @@ class MEDIA_EXPORT AudioParameters {
                                   // |channel_layout|.
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_AUDIO_PARAMETERS_H_
diff --git a/media/audio/audio_parameters_unittest.cc b/media/audio/audio_parameters_unittest.cc
index bd3334f..1a1140b 100644
--- a/media/audio/audio_parameters_unittest.cc
+++ b/media/audio/audio_parameters_unittest.cc
@@ -7,6 +7,8 @@
 #include "media/audio/audio_parameters.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+namespace media {
+
 TEST(AudioParameters, Constructor_Default) {
   AudioParameters::Format expected_format = AudioParameters::AUDIO_PCM_LINEAR;
   int expected_bits = 0;
@@ -163,3 +165,5 @@ TEST(AudioParameters, Compare) {
     EXPECT_FALSE(target(values[i], values[i]));
   }
 }
+
+}  // namespace media
diff --git a/media/audio/fake_audio_input_stream.cc b/media/audio/fake_audio_input_stream.cc
index d5ba994..47366a0 100644
--- a/media/audio/fake_audio_input_stream.cc
+++ b/media/audio/fake_audio_input_stream.cc
@@ -10,6 +10,8 @@
 using base::Time;
 using base::TimeDelta;
 
+namespace media {
+
 AudioInputStream* FakeAudioInputStream::MakeFakeStream(
     AudioManagerBase* manager,
     const AudioParameters& params) {
@@ -93,3 +95,5 @@ void FakeAudioInputStream::SetAutomaticGainControl(bool enabled) {}
 bool FakeAudioInputStream::GetAutomaticGainControl() {
   return false;
 }
+
+}  // namespace media
diff --git a/media/audio/fake_audio_input_stream.h b/media/audio/fake_audio_input_stream.h
index 409b799..ceed1a0 100644
--- a/media/audio/fake_audio_input_stream.h
+++ b/media/audio/fake_audio_input_stream.h
@@ -13,9 +13,11 @@
 #include "base/threading/thread.h"
 #include "base/time.h"
 #include "media/audio/audio_io.h"
-#include "media/audio/audio_parameters.h"
+
+namespace media {
 
 class AudioManagerBase;
+class AudioParameters;
 
 class MEDIA_EXPORT FakeAudioInputStream
     : public AudioInputStream {
@@ -52,4 +54,6 @@ class MEDIA_EXPORT FakeAudioInputStream
   DISALLOW_COPY_AND_ASSIGN(FakeAudioInputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_FAKE_AUDIO_INPUT_STREAM_H_
diff --git a/media/audio/fake_audio_output_stream.cc b/media/audio/fake_audio_output_stream.cc
index 14a38cd..686ccde 100644
--- a/media/audio/fake_audio_output_stream.cc
+++ b/media/audio/fake_audio_output_stream.cc
@@ -8,6 +8,8 @@
 #include "base/logging.h"
 #include "media/audio/audio_manager_base.h"
 
+namespace media {
+
 FakeAudioOutputStream* FakeAudioOutputStream::current_fake_stream_ = NULL;
 
 // static
@@ -70,3 +72,5 @@ FakeAudioOutputStream::~FakeAudioOutputStream() {
   if (current_fake_stream_ == this)
     current_fake_stream_ = NULL;
 }
+
+}  // namespace media
diff --git a/media/audio/fake_audio_output_stream.h b/media/audio/fake_audio_output_stream.h
index 19ed576..d4ab11a 100644
--- a/media/audio/fake_audio_output_stream.h
+++ b/media/audio/fake_audio_output_stream.h
@@ -15,6 +15,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerBase;
 
 class MEDIA_EXPORT FakeAudioOutputStream : public AudioOutputStream {
@@ -52,4 +54,6 @@ class MEDIA_EXPORT FakeAudioOutputStream : public AudioOutputStream {
   DISALLOW_COPY_AND_ASSIGN(FakeAudioOutputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_FAKE_AUDIO_OUTPUT_STREAM_H_
diff --git a/media/audio/linux/alsa_input.cc b/media/audio/linux/alsa_input.cc
index e28867f..84d2933 100644
--- a/media/audio/linux/alsa_input.cc
+++ b/media/audio/linux/alsa_input.cc
@@ -15,6 +15,8 @@
 #include "media/audio/linux/alsa_wrapper.h"
 #include "media/audio/linux/audio_manager_linux.h"
 
+namespace media {
+
 static const int kNumPacketsInRingBuffer = 3;
 
 static const char kDefaultDevice1[] = "default";
@@ -341,3 +343,5 @@ void AlsaPcmInputStream::HandleError(const char* method, int error) {
   LOG(WARNING) << method << ": " << wrapper_->StrError(error);
   callback_->OnError(this, error);
 }
+
+}  // namespace media
diff --git a/media/audio/linux/alsa_input.h b/media/audio/linux/alsa_input.h
index 6f6a981..ae027d4 100644
--- a/media/audio/linux/alsa_input.h
+++ b/media/audio/linux/alsa_input.h
@@ -17,6 +17,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AlsaWrapper;
 class AudioManagerLinux;
 
@@ -85,4 +87,6 @@ class AlsaPcmInputStream : public AudioInputStreamImpl {
   DISALLOW_COPY_AND_ASSIGN(AlsaPcmInputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_LINUX_ALSA_INPUT_H_
diff --git a/media/audio/linux/alsa_output.cc b/media/audio/linux/alsa_output.cc
index fc74180..d940be9 100644
--- a/media/audio/linux/alsa_output.cc
+++ b/media/audio/linux/alsa_output.cc
@@ -49,6 +49,8 @@
 #include "media/base/data_buffer.h"
 #include "media/base/seekable_buffer.h"
 
+namespace media {
+
 // Amount of time to wait if we've exhausted the data source.  This is to avoid
 // busy looping.
 static const uint32 kNoDataSleepMilliseconds = 10;
@@ -797,3 +799,5 @@ void AlsaPcmOutputStream::set_source_callback(AudioSourceCallback* callback) {
   DCHECK(IsOnAudioThread());
   source_callback_ = callback;
 }
+
+}  // namespace media
diff --git a/media/audio/linux/alsa_output.h b/media/audio/linux/alsa_output.h
index ee257eb..43e75bb 100644
--- a/media/audio/linux/alsa_output.h
+++ b/media/audio/linux/alsa_output.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 //
@@ -32,13 +32,13 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+class MessageLoop;
+
 namespace media {
-class SeekableBuffer;
-};  // namespace media
 
 class AlsaWrapper;
 class AudioManagerLinux;
-class MessageLoop;
+class SeekableBuffer;
 
 class MEDIA_EXPORT AlsaPcmOutputStream : public AudioOutputStream {
  public:
@@ -210,4 +210,6 @@ class MEDIA_EXPORT AlsaPcmOutputStream : public AudioOutputStream {
 MEDIA_EXPORT std::ostream& operator<<(std::ostream& os,
                                       AlsaPcmOutputStream::InternalState);
 
+};  // namespace media
+
 #endif  // MEDIA_AUDIO_LINUX_ALSA_OUTPUT_H_
diff --git a/media/audio/linux/alsa_output_unittest.cc b/media/audio/linux/alsa_output_unittest.cc
index ab9a654..be605c1 100644
--- a/media/audio/linux/alsa_output_unittest.cc
+++ b/media/audio/linux/alsa_output_unittest.cc
@@ -29,6 +29,8 @@ using testing::StrictMock;
 using testing::StrEq;
 using testing::Unused;
 
+namespace media {
+
 class MockAlsaWrapper : public AlsaWrapper {
  public:
   MOCK_METHOD3(DeviceNameHint, int(int card,
@@ -824,3 +826,5 @@ TEST_F(AlsaPcmOutputStreamTest, ScheduleNextWrite_StopStream) {
   test_stream->TransitionTo(AlsaPcmOutputStream::kIsClosed);
   test_stream->Close();
 }
+
+}  // namespace media
diff --git a/media/audio/linux/alsa_util.cc b/media/audio/linux/alsa_util.cc
index 5137119..176ef69 100644
--- a/media/audio/linux/alsa_util.cc
+++ b/media/audio/linux/alsa_util.cc
@@ -11,7 +11,7 @@
 
 namespace alsa_util {
 
-static snd_pcm_t* OpenDevice(AlsaWrapper* wrapper,
+static snd_pcm_t* OpenDevice(media::AlsaWrapper* wrapper,
                              const char* device_name,
                              snd_pcm_stream_t type,
                              int channels,
@@ -81,7 +81,7 @@ snd_pcm_format_t BitsToFormat(int bits_per_sample) {
   }
 }
 
-int CloseDevice(AlsaWrapper* wrapper, snd_pcm_t* handle) {
+int CloseDevice(media::AlsaWrapper* wrapper, snd_pcm_t* handle) {
   std::string device_name = wrapper->PcmName(handle);
   int error = wrapper->PcmClose(handle);
   if (error < 0) {
@@ -92,7 +92,7 @@ int CloseDevice(AlsaWrapper* wrapper, snd_pcm_t* handle) {
   return error;
 }
 
-snd_pcm_t* OpenCaptureDevice(AlsaWrapper* wrapper,
+snd_pcm_t* OpenCaptureDevice(media::AlsaWrapper* wrapper,
                              const char* device_name,
                              int channels,
                              int sample_rate,
@@ -102,7 +102,7 @@ snd_pcm_t* OpenCaptureDevice(AlsaWrapper* wrapper,
                     sample_rate, pcm_format, latency_us);
 }
 
-snd_pcm_t* OpenPlaybackDevice(AlsaWrapper* wrapper,
+snd_pcm_t* OpenPlaybackDevice(media::AlsaWrapper* wrapper,
                               const char* device_name,
                               int channels,
                               int sample_rate,
@@ -112,7 +112,7 @@ snd_pcm_t* OpenPlaybackDevice(AlsaWrapper* wrapper,
                     sample_rate, pcm_format, latency_us);
 }
 
-snd_mixer_t* OpenMixer(AlsaWrapper* wrapper,
+snd_mixer_t* OpenMixer(media::AlsaWrapper* wrapper,
                        const std::string& device_name) {
   snd_mixer_t* mixer = NULL;
 
@@ -143,7 +143,7 @@ snd_mixer_t* OpenMixer(AlsaWrapper* wrapper,
   return mixer;
 }
 
-void CloseMixer(AlsaWrapper* wrapper, snd_mixer_t* mixer,
+void CloseMixer(media::AlsaWrapper* wrapper, snd_mixer_t* mixer,
                 const std::string& device_name) {
   if (!mixer)
     return;
@@ -166,7 +166,7 @@ void CloseMixer(AlsaWrapper* wrapper, snd_mixer_t* mixer,
   }
 }
 
-snd_mixer_elem_t* LoadCaptureMixerElement(AlsaWrapper* wrapper,
+snd_mixer_elem_t* LoadCaptureMixerElement(media::AlsaWrapper* wrapper,
                                           snd_mixer_t* mixer) {
   if (!mixer)
     return NULL;
diff --git a/media/audio/linux/alsa_util.h b/media/audio/linux/alsa_util.h
index 054d24d..53cf80a 100644
--- a/media/audio/linux/alsa_util.h
+++ b/media/audio/linux/alsa_util.h
@@ -8,37 +8,40 @@
 #include <alsa/asoundlib.h>
 #include <string>
 
+namespace media {
 class AlsaWrapper;
+}
 
 namespace alsa_util {
 
 snd_pcm_format_t BitsToFormat(int bits_per_sample);
 
-snd_pcm_t* OpenCaptureDevice(AlsaWrapper* wrapper,
+snd_pcm_t* OpenCaptureDevice(media::AlsaWrapper* wrapper,
                              const char* device_name,
                              int channels,
                              int sample_rate,
                              snd_pcm_format_t pcm_format,
                              int latency_us);
 
-snd_pcm_t* OpenPlaybackDevice(AlsaWrapper* wrapper,
+snd_pcm_t* OpenPlaybackDevice(media::AlsaWrapper* wrapper,
                               const char* device_name,
                               int channels,
                               int sample_rate,
                               snd_pcm_format_t pcm_format,
                               int latency_us);
 
-int CloseDevice(AlsaWrapper* wrapper, snd_pcm_t* handle);
+int CloseDevice(media::AlsaWrapper* wrapper, snd_pcm_t* handle);
 
-snd_mixer_t* OpenMixer(AlsaWrapper* wrapper, const std::string& device_name);
+snd_mixer_t* OpenMixer(media::AlsaWrapper* wrapper,
+                       const std::string& device_name);
 
-void CloseMixer(AlsaWrapper* wrapper,
+void CloseMixer(media::AlsaWrapper* wrapper,
                 snd_mixer_t* mixer,
                 const std::string& device_name);
 
-snd_mixer_elem_t* LoadCaptureMixerElement(AlsaWrapper* wrapper,
+snd_mixer_elem_t* LoadCaptureMixerElement(media::AlsaWrapper* wrapper,
                                           snd_mixer_t* mixer);
 
-}
+}  // namespace alsa_util
 
 #endif  // MEDIA_AUDIO_LINUX_ALSA_UTIL_H_
diff --git a/media/audio/linux/alsa_wrapper.cc b/media/audio/linux/alsa_wrapper.cc
index 9e056d8..67331b4 100644
--- a/media/audio/linux/alsa_wrapper.cc
+++ b/media/audio/linux/alsa_wrapper.cc
@@ -6,6 +6,8 @@
 
 #include <alsa/asoundlib.h>
 
+namespace media {
+
 AlsaWrapper::AlsaWrapper() {
 }
 
@@ -226,3 +228,5 @@ int AlsaWrapper::MixerSelemGetCaptureVolumeRange(snd_mixer_elem_t* elem,
                                                  long* min, long* max) {
   return snd_mixer_selem_get_capture_volume_range(elem, min, max);
 }
+
+}  // namespace media
diff --git a/media/audio/linux/alsa_wrapper.h b/media/audio/linux/alsa_wrapper.h
index 49d64b2..30d9463 100644
--- a/media/audio/linux/alsa_wrapper.h
+++ b/media/audio/linux/alsa_wrapper.h
@@ -11,6 +11,8 @@
 #include "base/basictypes.h"
 #include "media/base/media_export.h"
 
+namespace media {
+
 class MEDIA_EXPORT AlsaWrapper {
  public:
   AlsaWrapper();
@@ -75,3 +77,5 @@ class MEDIA_EXPORT AlsaWrapper {
                         int soft_resample, unsigned int latency);
   DISALLOW_COPY_AND_ASSIGN(AlsaWrapper);
 };
+
+}  // namespace media
diff --git a/media/audio/linux/audio_manager_linux.cc b/media/audio/linux/audio_manager_linux.cc
index 27d5749..0b34aaa 100644
--- a/media/audio/linux/audio_manager_linux.cc
+++ b/media/audio/linux/audio_manager_linux.cc
@@ -23,6 +23,8 @@
 #include "media/base/limits.h"
 #include "media/base/media_switches.h"
 
+namespace media {
+
 // Maximum number of output streams that can be open simultaneously.
 static const int kMaxOutputStreams = 50;
 
@@ -309,3 +311,5 @@ AudioInputStream* AudioManagerLinux::MakeInputStream(
 AudioManager* CreateAudioManager() {
   return new AudioManagerLinux();
 }
+
+}  // namespace media
diff --git a/media/audio/linux/audio_manager_linux.h b/media/audio/linux/audio_manager_linux.h
index 81e53c4..d62d361 100644
--- a/media/audio/linux/audio_manager_linux.h
+++ b/media/audio/linux/audio_manager_linux.h
@@ -11,6 +11,8 @@
 #include "base/threading/thread.h"
 #include "media/audio/audio_manager_base.h"
 
+namespace media {
+
 class AlsaWrapper;
 
 class MEDIA_EXPORT AudioManagerLinux : public AudioManagerBase {
@@ -73,4 +75,6 @@ class MEDIA_EXPORT AudioManagerLinux : public AudioManagerBase {
   DISALLOW_COPY_AND_ASSIGN(AudioManagerLinux);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_LINUX_AUDIO_MANAGER_LINUX_H_
diff --git a/media/audio/mac/audio_input_mac.cc b/media/audio/mac/audio_input_mac.cc
index 0277a00..2ae1651 100644
--- a/media/audio/mac/audio_input_mac.cc
+++ b/media/audio/mac/audio_input_mac.cc
@@ -18,6 +18,8 @@ enum {
 };
 #endif
 
+namespace media {
+
 PCMQueueInAudioInputStream::PCMQueueInAudioInputStream(
     AudioManagerMac* manager, const AudioParameters& params)
     : manager_(manager),
@@ -217,3 +219,5 @@ void PCMQueueInAudioInputStream::HandleInputBuffer(
     HandleError(err);
   }
 }
+
+}  // namespace media
diff --git a/media/audio/mac/audio_input_mac.h b/media/audio/mac/audio_input_mac.h
index 1347871..d290bcb 100644
--- a/media/audio/mac/audio_input_mac.h
+++ b/media/audio/mac/audio_input_mac.h
@@ -12,6 +12,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerMac;
 
 // Implementation of AudioInputStream for Mac OS X using the audio queue service
@@ -78,4 +80,6 @@ class PCMQueueInAudioInputStream : public AudioInputStream {
   DISALLOW_COPY_AND_ASSIGN(PCMQueueInAudioInputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_MAC_AUDIO_INPUT_MAC_H_
diff --git a/media/audio/mac/audio_low_latency_input_mac.cc b/media/audio/mac/audio_low_latency_input_mac.cc
index 075b055..dc9bd8a 100644
--- a/media/audio/mac/audio_low_latency_input_mac.cc
+++ b/media/audio/mac/audio_low_latency_input_mac.cc
@@ -12,6 +12,8 @@
 #include "media/audio/audio_util.h"
 #include "media/audio/mac/audio_manager_mac.h"
 
+namespace media {
+
 static const int kMinIntervalBetweenVolumeUpdatesMs = 1000;
 
 static std::ostream& operator<<(std::ostream& os,
@@ -604,3 +606,5 @@ bool AUAudioInputStream::IsVolumeSettableOnChannel(int channel) {
                                                   &is_settable);
   return (result == noErr) ? is_settable : false;
 }
+
+}  // namespace media
diff --git a/media/audio/mac/audio_low_latency_input_mac.h b/media/audio/mac/audio_low_latency_input_mac.h
index d1e507f..d35e439 100644
--- a/media/audio/mac/audio_low_latency_input_mac.h
+++ b/media/audio/mac/audio_low_latency_input_mac.h
@@ -46,6 +46,8 @@
 #include "media/audio/audio_input_stream_impl.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerMac;
 
 class AUAudioInputStream : public AudioInputStreamImpl {
@@ -146,4 +148,6 @@ class AUAudioInputStream : public AudioInputStreamImpl {
   DISALLOW_COPY_AND_ASSIGN(AUAudioInputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_MAC_AUDIO_LOW_LATENCY_INPUT_MAC_H_
diff --git a/media/audio/mac/audio_low_latency_input_mac_unittest.cc b/media/audio/mac/audio_low_latency_input_mac_unittest.cc
index 139a860..8b6972c 100644
--- a/media/audio/mac/audio_low_latency_input_mac_unittest.cc
+++ b/media/audio/mac/audio_low_latency_input_mac_unittest.cc
@@ -20,6 +20,8 @@ using ::testing::AtLeast;
 using ::testing::Ge;
 using ::testing::NotNull;
 
+namespace media {
+
 ACTION_P3(CheckCountAndPostQuitTask, count, limit, loop) {
   if (++*count >= limit) {
     loop->PostTask(FROM_HERE, MessageLoop::QuitClosure());
@@ -307,3 +309,4 @@ TEST_F(MacAudioInputTest, DISABLED_AUAudioInputStreamRecordToFile) {
   ais->Close();
 }
 
+}  // namespace media
diff --git a/media/audio/mac/audio_low_latency_output_mac.cc b/media/audio/mac/audio_low_latency_output_mac.cc
index 39ebf1a..b1f15dd 100644
--- a/media/audio/mac/audio_low_latency_output_mac.cc
+++ b/media/audio/mac/audio_low_latency_output_mac.cc
@@ -12,6 +12,8 @@
 #include "media/audio/audio_util.h"
 #include "media/audio/mac/audio_manager_mac.h"
 
+namespace media {
+
 // Reorder PCM from AAC layout to Core Audio 5.1 layout.
 // TODO(fbarchard): Switch layout when ffmpeg is updated.
 template<class Format>
@@ -350,3 +352,5 @@ double AUAudioOutputStream::GetPlayoutLatency(
 
   return (delay_frames + hardware_latency_frames_);
 }
+
+}  // namespace media
diff --git a/media/audio/mac/audio_low_latency_output_mac.h b/media/audio/mac/audio_low_latency_output_mac.h
index bb9ce8d..45d9773 100644
--- a/media/audio/mac/audio_low_latency_output_mac.h
+++ b/media/audio/mac/audio_low_latency_output_mac.h
@@ -23,6 +23,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerMac;
 
 // Implementation of AudioOuputStream for Mac OS X using the
@@ -99,4 +101,6 @@ class AUAudioOutputStream : public AudioOutputStream {
   DISALLOW_COPY_AND_ASSIGN(AUAudioOutputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_MAC_AUDIO_LOW_LATENCY_OUTPUT_MAC_H_
diff --git a/media/audio/mac/audio_manager_mac.cc b/media/audio/mac/audio_manager_mac.cc
index 3b1161d..2bd8501 100644
--- a/media/audio/mac/audio_manager_mac.cc
+++ b/media/audio/mac/audio_manager_mac.cc
@@ -15,6 +15,8 @@
 #include "media/audio/mac/audio_output_mac.h"
 #include "media/base/limits.h"
 
+namespace media {
+
 // Maximum number of output streams that can be open simultaneously.
 static const int kMaxOutputStreams = 50;
 
@@ -293,3 +295,5 @@ AudioInputStream* AudioManagerMac::MakeLowLatencyInputStream(
 AudioManager* CreateAudioManager() {
   return new AudioManagerMac();
 }
+
+}  // namespace media
diff --git a/media/audio/mac/audio_manager_mac.h b/media/audio/mac/audio_manager_mac.h
index d54f293..54ff3a6 100644
--- a/media/audio/mac/audio_manager_mac.h
+++ b/media/audio/mac/audio_manager_mac.h
@@ -9,6 +9,8 @@
 #include "base/compiler_specific.h"
 #include "media/audio/audio_manager_base.h"
 
+namespace media {
+
 // Mac OS X implementation of the AudioManager singleton. This class is internal
 // to the audio output and only internal users can call methods not exposed by
 // the AudioManager class.
@@ -41,4 +43,6 @@ class MEDIA_EXPORT AudioManagerMac : public AudioManagerBase {
   DISALLOW_COPY_AND_ASSIGN(AudioManagerMac);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_MAC_AUDIO_MANAGER_MAC_H_
diff --git a/media/audio/mac/audio_output_mac.cc b/media/audio/mac/audio_output_mac.cc
index d2cdc57..06fc26f 100644
--- a/media/audio/mac/audio_output_mac.cc
+++ b/media/audio/mac/audio_output_mac.cc
@@ -13,6 +13,8 @@
 #include "media/audio/audio_util.h"
 #include "media/audio/mac/audio_manager_mac.h"
 
+namespace media {
+
 // A custom data structure to store information an AudioQueue buffer.
 struct AudioQueueUserData {
   AudioQueueUserData() : empty_buffer(false) {}
@@ -527,3 +529,5 @@ PCMQueueOutAudioOutputStream::GetSource() {
   base::AutoLock lock(source_lock_);
   return source_;
 }
+
+}  // namespace media
diff --git a/media/audio/mac/audio_output_mac.h b/media/audio/mac/audio_output_mac.h
index e033fc9..66f2941 100644
--- a/media/audio/mac/audio_output_mac.h
+++ b/media/audio/mac/audio_output_mac.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -14,6 +14,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerMac;
 
 // Implementation of AudioOuputStream for Mac OS X using the audio queue service
@@ -97,4 +99,6 @@ class PCMQueueOutAudioOutputStream : public AudioOutputStream {
   DISALLOW_COPY_AND_ASSIGN(PCMQueueOutAudioOutputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_MAC_AUDIO_OUTPUT_MAC_H_
diff --git a/media/audio/mac/audio_output_mac_unittest.cc b/media/audio/mac/audio_output_mac_unittest.cc
index 71a7f40..0724883 100644
--- a/media/audio/mac/audio_output_mac_unittest.cc
+++ b/media/audio/mac/audio_output_mac_unittest.cc
@@ -20,6 +20,8 @@ using ::testing::NiceMock;
 using ::testing::NotNull;
 using ::testing::Return;
 
+namespace media {
+
 class MockAudioSource : public AudioOutputStream::AudioSourceCallback {
  public:
   MOCK_METHOD4(OnMoreData, uint32(AudioOutputStream* stream, uint8* dest,
@@ -175,3 +177,5 @@ TEST(MacAudioTest, PCMWaveStreamPendingBytes) {
   oas->Stop();
   oas->Close();
 }
+
+}  // namespace media
diff --git a/media/audio/openbsd/audio_manager_openbsd.cc b/media/audio/openbsd/audio_manager_openbsd.cc
index acdcea4..0f4314c 100644
--- a/media/audio/openbsd/audio_manager_openbsd.cc
+++ b/media/audio/openbsd/audio_manager_openbsd.cc
@@ -15,6 +15,8 @@
 
 #include <fcntl.h>
 
+namespace media {
+
 // Maximum number of output streams that can be open simultaneously.
 static const int kMaxOutputStreams = 50;
 
@@ -103,3 +105,5 @@ AudioOutputStream* AudioManagerOpenBSD::MakeOutputStream(
 AudioManager* CreateAudioManager() {
   return new AudioManagerOpenBSD();
 }
+
+}  // namespace media
diff --git a/media/audio/openbsd/audio_manager_openbsd.h b/media/audio/openbsd/audio_manager_openbsd.h
index 86b56c0..1635571 100644
--- a/media/audio/openbsd/audio_manager_openbsd.h
+++ b/media/audio/openbsd/audio_manager_openbsd.h
@@ -10,6 +10,8 @@
 #include "base/compiler_specific.h"
 #include "media/audio/audio_manager_base.h"
 
+namespace media {
+
 class MEDIA_EXPORT AudioManagerOpenBSD : public AudioManagerBase {
  public:
   AudioManagerOpenBSD();
@@ -43,4 +45,6 @@ class MEDIA_EXPORT AudioManagerOpenBSD : public AudioManagerBase {
   DISALLOW_COPY_AND_ASSIGN(AudioManagerOpenBSD);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_OPENBSD_AUDIO_MANAGER_OPENBSD_H_
diff --git a/media/audio/pulse/pulse_output.cc b/media/audio/pulse/pulse_output.cc
index c58d5bf..651d1f7 100644
--- a/media/audio/pulse/pulse_output.cc
+++ b/media/audio/pulse/pulse_output.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -16,6 +16,8 @@
 #include "media/base/data_buffer.h"
 #include "media/base/seekable_buffer.h"
 
+namespace media {
+
 static pa_sample_format_t BitsToPASampleFormat(int bits_per_sample) {
   switch (bits_per_sample) {
     // Unsupported sample formats shown for reference.  I am assuming we want
@@ -426,3 +428,5 @@ uint32 PulseAudioOutputStream::RunDataCallback(
 
   return 0;
 }
+
+}  // namespace media
diff --git a/media/audio/pulse/pulse_output.h b/media/audio/pulse/pulse_output.h
index 410ffb3..3c1cae6 100644
--- a/media/audio/pulse/pulse_output.h
+++ b/media/audio/pulse/pulse_output.h
@@ -27,8 +27,8 @@
 #include "media/base/channel_layout.h"
 
 namespace media {
+
 class SeekableBuffer;
-}
 
 #if defined(OS_LINUX)
 class AudioManagerLinux;
@@ -130,4 +130,6 @@ class PulseAudioOutputStream : public AudioOutputStream {
   DISALLOW_COPY_AND_ASSIGN(PulseAudioOutputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_PULSE_PULSE_OUTPUT_H_
diff --git a/media/audio/simple_sources.cc b/media/audio/simple_sources.cc
index d2dc584..8b85961 100644
--- a/media/audio/simple_sources.cc
+++ b/media/audio/simple_sources.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -13,6 +13,8 @@
 #include "media/audio/audio_io.h"
 #include "media/base/data_buffer.h"
 
+namespace media {
+
 //////////////////////////////////////////////////////////////////////////////
 // SineWaveAudioSource implementation.
 
@@ -96,3 +98,5 @@ void PushSource::ClearAll() {
 void PushSource::CleanUp() {
   buffer_.Clear();
 }
+
+}  // namespace media
diff --git a/media/audio/simple_sources.h b/media/audio/simple_sources.h
index a4373a0..fa06857 100644
--- a/media/audio/simple_sources.h
+++ b/media/audio/simple_sources.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -10,6 +10,8 @@
 #include "media/audio/audio_io.h"
 #include "media/base/seekable_buffer.h"
 
+namespace media {
+
 // An audio source that produces a pure sinusoidal tone.
 class MEDIA_EXPORT SineWaveAudioSource
     : public AudioOutputStream::AudioSourceCallback {
@@ -88,4 +90,6 @@ class MEDIA_EXPORT PushSource
   media::SeekableBuffer buffer_;
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_SIMPLE_SOURCES_H_
diff --git a/media/audio/simple_sources_unittest.cc b/media/audio/simple_sources_unittest.cc
index 384ed0b..1e19fd8 100644
--- a/media/audio/simple_sources_unittest.cc
+++ b/media/audio/simple_sources_unittest.cc
@@ -11,6 +11,8 @@
 #include "media/audio/simple_sources.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+namespace media {
+
 static void GenerateRandomData(char* buffer, uint32 len) {
   static bool called = false;
   if (!called) {
@@ -99,3 +101,5 @@ TEST(SimpleSources, SineWaveAudio16MonoTest) {
   EXPECT_TRUE(last_buffer[half_period + 2] > last_buffer[half_period + 3]);
   oas->Close();
 }
+
+}  // namespace media
diff --git a/media/audio/win/audio_low_latency_input_win.cc b/media/audio/win/audio_low_latency_input_win.cc
index 214b8bf9..20fbe71 100644
--- a/media/audio/win/audio_low_latency_input_win.cc
+++ b/media/audio/win/audio_low_latency_input_win.cc
@@ -14,6 +14,8 @@
 using base::win::ScopedComPtr;
 using base::win::ScopedCOMInitializer;
 
+namespace media {
+
 WASAPIAudioInputStream::WASAPIAudioInputStream(
     AudioManagerWin* manager, const AudioParameters& params,
     const std::string& device_id)
@@ -641,3 +643,5 @@ HRESULT WASAPIAudioInputStream::InitializeAudioEngine() {
                                  simple_audio_volume_.ReceiveVoid());
   return hr;
 }
+
+}  // namespace media
diff --git a/media/audio/win/audio_low_latency_input_win.h b/media/audio/win/audio_low_latency_input_win.h
index d546829..bb0f58c 100644
--- a/media/audio/win/audio_low_latency_input_win.h
+++ b/media/audio/win/audio_low_latency_input_win.h
@@ -77,6 +77,8 @@
 #include "media/audio/audio_parameters.h"
 #include "media/base/media_export.h"
 
+namespace media {
+
 class AudioManagerWin;
 
 // AudioInputStream implementation using Windows Core Audio APIs.
@@ -210,4 +212,6 @@ class MEDIA_EXPORT WASAPIAudioInputStream
   DISALLOW_COPY_AND_ASSIGN(WASAPIAudioInputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_WIN_AUDIO_LOW_LATENCY_INPUT_WIN_H_
diff --git a/media/audio/win/audio_low_latency_input_win_unittest.cc b/media/audio/win/audio_low_latency_input_win_unittest.cc
index da5acb6..029403f 100644
--- a/media/audio/win/audio_low_latency_input_win_unittest.cc
+++ b/media/audio/win/audio_low_latency_input_win_unittest.cc
@@ -27,6 +27,8 @@ using ::testing::AtLeast;
 using ::testing::Gt;
 using ::testing::NotNull;
 
+namespace media {
+
 ACTION_P3(CheckCountAndPostQuitTask, count, limit, loop) {
   if (++*count >= limit) {
     loop->PostTask(FROM_HERE, MessageLoop::QuitClosure());
@@ -392,3 +394,5 @@ TEST(WinAudioInputTest, DISABLED_WASAPIAudioInputStreamRecordToFile) {
   LOG(INFO) << ">> Recording has stopped.";
   ais->Close();
 }
+
+}  // namespace media
diff --git a/media/audio/win/audio_low_latency_output_win.cc b/media/audio/win/audio_low_latency_output_win.cc
index 120a397..ec0fcd2 100644
--- a/media/audio/win/audio_low_latency_output_win.cc
+++ b/media/audio/win/audio_low_latency_output_win.cc
@@ -16,6 +16,8 @@
 using base::win::ScopedComPtr;
 using base::win::ScopedCOMInitializer;
 
+namespace media {
+
 WASAPIAudioOutputStream::WASAPIAudioOutputStream(AudioManagerWin* manager,
                                                  const AudioParameters& params,
                                                  ERole device_role)
@@ -808,3 +810,5 @@ bool WASAPIAudioOutputStream::RestartRenderingUsingNewDefaultDevice() {
   restart_rendering_mode_ = false;
   return SUCCEEDED(hr);
 }
+
+}  // namespace media
diff --git a/media/audio/win/audio_low_latency_output_win.h b/media/audio/win/audio_low_latency_output_win.h
index 63a1c52..67a5d6c 100644
--- a/media/audio/win/audio_low_latency_output_win.h
+++ b/media/audio/win/audio_low_latency_output_win.h
@@ -132,6 +132,8 @@
 #include "media/audio/audio_parameters.h"
 #include "media/base/media_export.h"
 
+namespace media {
+
 class AudioManagerWin;
 
 // AudioOutputStream implementation using Windows Core Audio APIs.
@@ -307,4 +309,6 @@ class MEDIA_EXPORT WASAPIAudioOutputStream
   DISALLOW_COPY_AND_ASSIGN(WASAPIAudioOutputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_WIN_AUDIO_LOW_LATENCY_OUTPUT_WIN_H_
diff --git a/media/audio/win/audio_manager_win.cc b/media/audio/win/audio_manager_win.cc
index 1d19fe1..93dcf2f 100644
--- a/media/audio/win/audio_manager_win.cc
+++ b/media/audio/win/audio_manager_win.cc
@@ -38,6 +38,8 @@
 DEFINE_GUID(AM_KSCATEGORY_AUDIO, 0x6994ad04, 0x93ef, 0x11d0,
             0xa3, 0xcc, 0x00, 0xa0, 0xc9, 0x22, 0x31, 0x96);
 
+namespace media {
+
 // Maximum number of output streams that can be open simultaneously.
 static const int kMaxOutputStreams = 50;
 
@@ -317,3 +319,5 @@ AudioInputStream* AudioManagerWin::CreatePCMWaveInAudioInputStream(
 AudioManager* CreateAudioManager() {
   return new AudioManagerWin();
 }
+
+}  // namespace media
diff --git a/media/audio/win/audio_manager_win.h b/media/audio/win/audio_manager_win.h
index 19742fb..b1e2426 100644
--- a/media/audio/win/audio_manager_win.h
+++ b/media/audio/win/audio_manager_win.h
@@ -13,6 +13,8 @@
 #include "base/gtest_prod_util.h"
 #include "media/audio/audio_manager_base.h"
 
+namespace media {
+
 // Windows implementation of the AudioManager singleton. This class is internal
 // to the audio output and only internal users can call methods not exposed by
 // the AudioManager class.
@@ -71,4 +73,6 @@ class MEDIA_EXPORT AudioManagerWin : public AudioManagerBase {
   DISALLOW_COPY_AND_ASSIGN(AudioManagerWin);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_WIN_AUDIO_MANAGER_WIN_H_
diff --git a/media/audio/win/audio_output_win_unittest.cc b/media/audio/win/audio_output_win_unittest.cc
index a6e240d..11b5693 100644
--- a/media/audio/win/audio_output_win_unittest.cc
+++ b/media/audio/win/audio_output_win_unittest.cc
@@ -31,6 +31,8 @@ using ::testing::Return;
 
 using base::win::ScopedCOMInitializer;
 
+namespace media {
+
 static const wchar_t kAudioFile1_16b_m_16K[]
     = L"media\\test\\data\\sweep02_16b_mono_16KHz.raw";
 
@@ -744,3 +746,5 @@ TEST(WinAudioTest, SyncSocketBasic) {
   oas->Stop();
   oas->Close();
 }
+
+}  // namespace media
diff --git a/media/audio/win/wavein_input_win.cc b/media/audio/win/wavein_input_win.cc
index f4055db..7eb778d 100644
--- a/media/audio/win/wavein_input_win.cc
+++ b/media/audio/win/wavein_input_win.cc
@@ -16,7 +16,7 @@ namespace {
 const int kStopInputStreamCallbackTimeout = 3000;  // Three seconds.
 }
 
-using media::AudioDeviceNames;
+namespace media {
 
 // Our sound buffers are allocated once and kept in a linked list using the
 // the WAVEHDR::dwUser variable. The last buffer points to the first buffer.
@@ -297,3 +297,5 @@ void PCMWaveInAudioInputStream::WaveCallback(HWAVEIN hwi, UINT msg,
       obj->callback_->OnClose(obj);
   }
 }
+
+}  // namespace media
diff --git a/media/audio/win/wavein_input_win.h b/media/audio/win/wavein_input_win.h
index b4418d8..82f1f55 100644
--- a/media/audio/win/wavein_input_win.h
+++ b/media/audio/win/wavein_input_win.h
@@ -16,6 +16,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerWin;
 
 class PCMWaveInAudioInputStream : public AudioInputStream {
@@ -117,4 +119,6 @@ class PCMWaveInAudioInputStream : public AudioInputStream {
   DISALLOW_COPY_AND_ASSIGN(PCMWaveInAudioInputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_WIN_WAVEIN_INPUT_WIN_H_
diff --git a/media/audio/win/waveout_output_win.cc b/media/audio/win/waveout_output_win.cc
index c8c7523..3cae68c 100644
--- a/media/audio/win/waveout_output_win.cc
+++ b/media/audio/win/waveout_output_win.cc
@@ -15,6 +15,8 @@
 #include "media/audio/audio_util.h"
 #include "media/audio/win/audio_manager_win.h"
 
+namespace media {
+
 // Some general thoughts about the waveOut API which is badly documented :
 // - We use CALLBACK_EVENT mode in which XP signals events such as buffer
 //   releases.
@@ -411,3 +413,5 @@ void NTAPI PCMWaveOutAudioOutputStream::BufferCallback(PVOID lpParameter,
     }
   }
 }
+
+}  // namespace media
diff --git a/media/audio/win/waveout_output_win.h b/media/audio/win/waveout_output_win.h
index e7cb4ed..bc53bb4 100644
--- a/media/audio/win/waveout_output_win.h
+++ b/media/audio/win/waveout_output_win.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -17,6 +17,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerWin;
 
 // Implements PCM audio output support for Windows using the WaveXXX API.
@@ -132,4 +134,6 @@ class PCMWaveOutAudioOutputStream : public AudioOutputStream {
   DISALLOW_COPY_AND_ASSIGN(PCMWaveOutAudioOutputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_WIN_WAVEOUT_OUTPUT_WIN_H_
diff --git a/media/tools/player_wtl/movie.cc b/media/tools/player_wtl/movie.cc
index 4e3c9ab..781f377 100644
--- a/media/tools/player_wtl/movie.cc
+++ b/media/tools/player_wtl/movie.cc
@@ -20,13 +20,6 @@
 #include "media/filters/null_audio_renderer.h"
 #include "media/filters/video_renderer_base.h"
 
-using media::FFmpegAudioDecoder;
-using media::FFmpegDemuxer;
-using media::FFmpegVideoDecoder;
-using media::FileDataSource;
-using media::FilterCollection;
-using media::Pipeline;
-
 namespace media {
 
 Movie::Movie()
diff --git a/media/tools/player_wtl/movie.h b/media/tools/player_wtl/movie.h
index 54ddd49..0e04278 100644
--- a/media/tools/player_wtl/movie.h
+++ b/media/tools/player_wtl/movie.h
@@ -13,11 +13,11 @@
 #include "base/memory/scoped_ptr.h"
 #include "media/base/message_loop_factory.h"
 
-class AudioManager;
 template <typename T> struct DefaultSingletonTraits;
 
 namespace media {
 
+class AudioManager;
 class Pipeline;
 class VideoRendererBase;
 
diff --git a/media/tools/player_x11/player_x11.cc b/media/tools/player_x11/player_x11.cc
index 467d92f..ce2ff07 100644
--- a/media/tools/player_x11/player_x11.cc
+++ b/media/tools/player_x11/player_x11.cc
@@ -37,7 +37,7 @@ static Display* g_display = NULL;
 static Window g_window = 0;
 static bool g_running = false;
 
-AudioManager* g_audio_manager = NULL;
+media::AudioManager* g_audio_manager = NULL;
 
 media::VideoRendererBase* g_video_renderer = NULL;
 
@@ -238,7 +238,7 @@ int main(int argc, char** argv) {
     return 1;
   }
 
-  scoped_ptr<AudioManager> audio_manager(AudioManager::Create());
+  scoped_ptr<media::AudioManager> audio_manager(media::AudioManager::Create());
   g_audio_manager = audio_manager.get();
 
   logging::InitLogging(