summaryrefslogtreecommitdiffstats
path: root/media/audio/audio_output_proxy.h
diff options
context:
space:
mode:
authorsergeyu@chromium.org <sergeyu@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>2010-11-24 22:22:46 +0000
committersergeyu@chromium.org <sergeyu@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>2010-11-24 22:22:46 +0000
commite667807890b931d41a4529165bedef5203382bbd (patch)
tree1ac7430f2e9cd9d6000fdc8fbff28d17c42ad3c6 /media/audio/audio_output_proxy.h
parentc78a2fa648c28bd7874df7b65962975bea027ea0 (diff)
downloadchromium_src-e667807890b931d41a4529165bedef5203382bbd.zip
chromium_src-e667807890b931d41a4529165bedef5203382bbd.tar.gz
chromium_src-e667807890b931d41a4529165bedef5203382bbd.tar.bz2
Implemented AudioOutputProxy.
AudioOutputProxy implements AudioOutputStream interface, but opens audio device only when audio is playing. BUG=39825 TEST=Unittests. Review URL: http://codereview.chromium.org/5158003 git-svn-id: svn://svn.chromium.org/chrome/trunk/src@67327 0039d316-1c4b-4281-b951-d872f2087c98
Diffstat (limited to 'media/audio/audio_output_proxy.h')
-rw-r--r--media/audio/audio_output_proxy.h64
1 files changed, 64 insertions, 0 deletions
diff --git a/media/audio/audio_output_proxy.h b/media/audio/audio_output_proxy.h
new file mode 100644
index 0000000..4835cc8
--- /dev/null
+++ b/media/audio/audio_output_proxy.h
@@ -0,0 +1,64 @@
+// Copyright (c) 2010 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.
+
+#ifndef MEDIA_AUDIO_AUDIO_OUTPUT_STREAM_PROXY_H_
+#define MEDIA_AUDIO_AUDIO_OUTPUT_STREAM_PROXY_H_
+
+#include "base/basictypes.h"
+#include "base/task.h"
+#include "media/audio/audio_io.h"
+#include "media/audio/audio_parameters.h"
+
+class AudioOutputDispatcher;
+
+// AudioOutputProxy is an audio otput stream that uses resources more
+// efficiently than a regular audio output stream: it opens audio
+// device only when sound is playing, i.e. between Start() and Stop()
+// (there is still one physical stream per each audio output proxy in
+// playing state).
+//
+// AudioOutputProxy uses AudioOutputDispatcher to open and close
+// physical output streams.
+class AudioOutputProxy : public AudioOutputStream {
+ public:
+ // Caller keeps ownership of |dispatcher|.
+ AudioOutputProxy(AudioOutputDispatcher* dispatcher);
+
+ // AudioOutputStream interface.
+ virtual bool Open();
+ virtual void Start(AudioSourceCallback* callback);
+ virtual void Stop();
+ virtual void SetVolume(double volume);
+ virtual void GetVolume(double* volume);
+ virtual void Close();
+
+ private:
+ // Needs to access destructor.
+ friend class DeleteTask<AudioOutputProxy>;
+
+ enum State {
+ kCreated,
+ kOpened,
+ kPlaying,
+ kClosed,
+ kError,
+ };
+
+ virtual ~AudioOutputProxy();
+
+ scoped_refptr<AudioOutputDispatcher> dispatcher_;
+ State state_;
+
+ // The actual audio stream. Must be set to NULL in any state other
+ // than kPlaying.
+ AudioOutputStream* physical_stream_;
+
+ // Need to save volume here, so that we can restore it in case the stream
+ // is stopped, and then started again.
+ double volume_;
+
+ DISALLOW_COPY_AND_ASSIGN(AudioOutputProxy);
+};
+
+#endif // MEDIA_AUDIO_AUDIO_OUTPUT_STREAM_PROXY_H_