blob: f936c7c6be65b15a82ab444a7d4b3d1de4880578 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
|
// Copyright (c) 2011 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 CHROME_BROWSER_CHROMEOS_AUDIO_MIXER_H_
#define CHROME_BROWSER_CHROMEOS_AUDIO_MIXER_H_
#pragma once
#include "base/basictypes.h"
#include "base/callback_old.h"
namespace chromeos {
class AudioMixer {
public:
// Approximation of pure silence expressed in decibels.
static const double kSilenceDb;
enum State {
UNINITIALIZED = 0,
INITIALIZING,
READY,
SHUTTING_DOWN,
IN_ERROR,
};
AudioMixer() {}
virtual ~AudioMixer() {}
// Non-Blocking call. Connect to Mixer, find a default device, then call the
// callback when complete with success code.
typedef Callback1<bool>::Type InitDoneCallback;
virtual void Init(InitDoneCallback* callback) = 0;
// Call may block. Mixer will be connected before returning, unless error.
virtual bool InitSync() = 0;
// Call may block. Returns a default of kSilenceDb on error.
virtual double GetVolumeDb() const = 0;
// Non-Blocking call. Returns the actual volume limits possible according
// to the mixer. Limits are left unchanged on error
virtual bool GetVolumeLimits(double* vol_min, double* vol_max) = 0;
// Non-blocking call.
virtual void SetVolumeDb(double vol_db) = 0;
// Call may block. Gets the mute state of the default device (true == mute).
// Returns a default of false on error.
virtual bool IsMute() const = 0;
// Non-Blocking call.
virtual void SetMute(bool mute) = 0;
// Returns READY if we have a valid working connection to the Mixer.
// This can return IN_ERROR if we lose the connection, even after an original
// successful init. Non-blocking call.
virtual State GetState() const = 0;
private:
DISALLOW_COPY_AND_ASSIGN(AudioMixer);
};
} // namespace chromeos
#endif // CHROME_BROWSER_CHROMEOS_AUDIO_MIXER_H_
|
