我创建了一个带有示例项目的 GitHub 存储库,该项目显示了我在这里询问的以下问题:
https
://github.com/paulpv/audio-loopback/tree/simplified/src/com/twistpair/wave/experimental/loopback
(请坚持使用“简化”分支并忽略“主”分支)
两个主要文件是:
- https://github.com/paulpv/audio-loopback/blob/simplified/src/com/twistpair/wave/experimental/loopback/MainActivity.java
- https://github.com/paulpv/audio-loopback/blob/simplified/src/com/twistpair/wave/experimental/loopback/AudioStateManager.java
免责声明:我目前只使用一个运行 CyanogenMod 10 Jelly Bean 的三星 Epic SPH-D700 来进行编码和测试。我没有在其他设备上尝试过这个,但也许这可能有助于阻止我把头发拉出来发疯。
几个月来,我一直在努力让 Android 蓝牙 SCO可靠地启动和停止以及捕获/播放音频!
一旦我可以让手机进入 SCO 模式,通过 AudioRecord 和 AudioTrack(分别)捕获和播放就可以正常工作,如文档所述。
我遇到的问题是我无法可靠地将手机置于 SCO 模式!
“互联网”上使用 startBluetoothSco() 和 setBluetoothScoOn(true) 的示例看起来都很简单直接,但是当我在我的设备上使用它们时,它们几乎无法可靠地工作。
我创建了自己的测试应用程序,除了启动和停止 SCO 什么都不做,我什至无法让它可靠地工作!
我的代码监听BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED EXTRA_STATE==CONNECTED.
我可以可靠地检测到任何耳机何时连接或断开。
当检测到连接时,我的处理程序立即调用 startBluetoothSco()。
A 可以发誓至少一旦这踢到SCO_AUDIO_STATE
了 C O
NNECTED,但 99% 的时间它只是导致从DISCONNECTED->CONNECTING->DISCONNECTED
.
这是我的 GitHub 示例应用程序的注释日志输出:
10-03 17:00:13.970: I/dalvikvm(29487): Debugger is active
10-03 17:00:14.158: I/System.out(29487): Debugger has connected
10-03 17:00:15.779: I/System.out(29487): waiting for debugger to settle...
10-03 17:00:15.978: I/System.out(29487): debugger has settled (1325)
我的应用程序在关闭 Jawbone 耳机的情况下启动并更新 UI...
10-03 17:00:16.568: D/MainActivity(29487): updateScreen()...
10-03 17:00:16.572: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=false
...UI 更新完成
Sticky 广播,告诉我当前的 SCO_AUDIO_STATE...
10-03 17:00:16.689: D/AudioStateManager(29487): onReceive: intent=Intent { act=android.media.ACTION_SCO_AUDIO_STATE_UPDATED flg=0x10 (has extras) }
10-03 17:00:16.689: D/AudioStateManager(29487): extras={"android.media.extra.SCO_AUDIO_PREVIOUS_STATE"=2, "android.media.extra.SCO_AUDIO_STATE"=0}
10-03 17:00:16.689: D/AudioStateManager(29487): android.media.ACTION_SCO_AUDIO_STATE_UPDATED
10-03 17:00:16.693: D/AudioStateManager(29487): ==> scoAudioStatePrevious=SCO_AUDIO_STATE_CONNECTING(2)
10-03 17:00:16.693: D/AudioStateManager(29487): ==> scoAudioState=SCO_AUDIO_STATE_DISCONNECTED(0)
10-03 17:00:16.693: D/AudioStateManager(29487): android.media.ACTION_SCO_AUDIO_STATE_UPDATED: SCO_AUDIO_STATE_DISCONNECTED
...当前 SCO_AUDIO_STATE == DISCONNECTED; 预期,因为我的耳机已关闭。
调用我的 SCO Disconnected 事件侦听器并使用两个 sendMessage 更新 UI...
10-03 17:00:16.693: I/MainActivity(29487): onAudioManagerScoAudioDisconnected()
10-03 17:00:16.755: D/libEGL(29487): loaded /vendor/lib/egl/libEGL_POWERVR_SGX540_120.so
10-03 17:00:16.787: D/libEGL(29487): loaded /vendor/lib/egl/libGLESv1_CM_POWERVR_SGX540_120.so
10-03 17:00:16.791: D/libEGL(29487): loaded /vendor/lib/egl/libGLESv2_POWERVR_SGX540_120.so
10-03 17:00:16.888: D/OpenGLRenderer(29487): Enabling debug mode 0
10-03 17:00:16.912: D/MainActivity(29487): MSG_UPDATE_BLUETOOTH_INDICATION
10-03 17:00:16.912: D/MainActivity(29487): updateScreen()...
10-03 17:00:16.912: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=false
10-03 17:00:16.927: D/MainActivity(29487): MSG_UPDATE_AUDIO_OUTPUT_STREAM_TYPE
10-03 17:00:16.927: D/MainActivity(29487): updateScreen()...
10-03 17:00:16.931: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=false
...UI 更新完成
大约 20 秒后,我打开了 Jawbone 耳机……
10-03 17:00:37.572: D/AudioStateManager(29487): onReceive: intent=Intent { act=android.bluetooth.headset.profile.action.CONNECTION_STATE_CHANGED flg=0x10 (has extras) }
10-03 17:00:37.583: D/AudioStateManager(29487): extras={"android.bluetooth.device.extra.DEVICE"=00:21:3C:00:3E:02, "android.bluetooth.profile.extra.PREVIOUS_STATE"=0, "android.bluetooth.profile.extra.STATE"=1}
10-03 17:00:37.587: D/AudioStateManager(29487): mReceiver: BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED
10-03 17:00:37.587: D/AudioStateManager(29487): ==> bluetoothDevice=00:21:3C:00:3E:02
10-03 17:00:37.587: D/AudioStateManager(29487): ==> bluetoothHeadsetStatePrevious=STATE_DISCONNECTED(0)
10-03 17:00:37.587: D/AudioStateManager(29487): ==> bluetoothHeadsetState=STATE_CONNECTING(1)
10-03 17:00:37.619: D/AudioStateManager(29487): onReceive: intent=Intent { act=android.bluetooth.headset.profile.action.CONNECTION_STATE_CHANGED flg=0x10 (has extras) }
10-03 17:00:37.623: D/AudioStateManager(29487): extras={"android.bluetooth.device.extra.DEVICE"=00:21:3C:00:3E:02, "android.bluetooth.profile.extra.PREVIOUS_STATE"=1, "android.bluetooth.profile.extra.STATE"=2}
10-03 17:00:37.623: D/AudioStateManager(29487): mReceiver: BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED
10-03 17:00:37.623: D/AudioStateManager(29487): ==> bluetoothDevice=00:21:3C:00:3E:02
10-03 17:00:37.626: D/AudioStateManager(29487): ==> bluetoothHeadsetStatePrevious=STATE_CONNECTING(1)
10-03 17:00:37.626: D/AudioStateManager(29487): ==> bluetoothHeadsetState=STATE_CONNECTED(2)
颚骨连接;我的事件侦听器被称为...
10-03 17:00:37.626: I/MainActivity(29487): onBluetoothHeadsetConnected()
...看到我们可以SCO...
10-03 17:00:37.626: D/AudioStateManager(29487): mAudioManager.isBluetoothScoAvailableOffCall()=true
...并自动调用 startBluetoothSco()这就是问题所在
!为什么这个对 startBluetoothSco 的调用不会导致 SCO_AUDIO_STATE == CONNECTED?!?!
10-03 17:00:37.626: D/AudioStateManager(29487): startBluetoothSco()
10-03 17:00:37.626: I/AudioStateManager(29487): mAudioManager.startBluetoothSco();
我的事件监听器完成了带有 sendMessage 以更新带有当前 BT 状态的 UI ...
10-03 17:00:37.646: D/MainActivity(29487): MSG_UPDATE_BLUETOOTH_INDICATION
10-03 17:00:37.650: D/MainActivity(29487): updateScreen()...
10-03 17:00:37.650: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=false
... UI 更新完成
startBluetoothSco 的第一个结果进来...
10-03 17:00:37.681: D/AudioStateManager(29487): onReceive: intent=Intent { act=android.media.ACTION_SCO_AUDIO_STATE_UPDATED flg=0x10 (has extras) }
10-03 17:00:37.681: D/AudioStateManager(29487): extras={"android.media.extra.SCO_AUDIO_STATE"=2, "android.media.extra.SCO_AUDIO_PREVIOUS_STATE"=0}
10-03 17:00:37.681: D/AudioStateManager(29487): android.media.ACTION_SCO_AUDIO_STATE_UPDATED
10-03 17:00:37.685: D/AudioStateManager(29487): ==> scoAudioStatePrevious=SCO_AUDIO_STATE_DISCONNECTED(0)
10-03 17:00:37.685: D/AudioStateManager(29487): ==> scoAudioState=SCO_AUDIO_STATE_CONNECTING(2)
...从 DISCONNECTED 移动到 CONNECTING
来自 startBluetoothSco 的第二个结果进来...
10-03 17:00:37.759: D/AudioStateManager(29487): onReceive: intent=Intent { act=android.media.ACTION_SCO_AUDIO_STATE_UPDATED flg=0x10 (has extras) }
10-03 17:00:37.763: D/AudioStateManager(29487): extras={"android.media.extra.SCO_AUDIO_STATE"=0, "android.media.extra.SCO_AUDIO_PREVIOUS_STATE"=2}
10-03 17:00:37.763: D/AudioStateManager(29487): android.media.ACTION_SCO_AUDIO_STATE_UPDATED
10-03 17:00:37.763: D/AudioStateManager(29487): ==> scoAudioStatePrevious=SCO_AUDIO_STATE_CONNECTING(2)
10-03 17:00:37.763: D/AudioStateManager(29487): ==> scoAudioState=SCO_AUDIO_STATE_DISCONNECTED(0)
10-03 17:00:37.763: D/AudioStateManager(29487): android.media.ACTION_SCO_AUDIO_STATE_UPDATED: SCO_AUDIO_STATE_DISCONNECTED
...从 CONNECTING 移动到DISCONNECTED
我本来希望 SCO 从 CONNECTING 到CONNECTED!
我的事件侦听器被调用并使用两个 sendMessages 更新 UI ...
10-03 17:00:37.763: I/MainActivity(29487): onAudioManagerScoAudioDisconnected()
10-03 17:00:37.767: D/MainActivity(29487): MSG_UPDATE_BLUETOOTH_INDICATION
10-03 17:00:37.767: D/MainActivity(29487): updateScreen()...
10-03 17:00:37.767: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=false
10-03 17:00:37.783: D/MainActivity(29487): MSG_UPDATE_AUDIO_OUTPUT_STREAM_TYPE
10-03 17:00:37.783: D/MainActivity(29487): updateScreen()...
10-03 17:00:37.783: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=false
...UI 更新完成
我等待 20 秒左右 SCO 连接,但它永远不会出现。
我按下我的应用程序的“startBluetoothSco”按钮。
请注意,这会导致在 17:00:37.626 对 startBluetoothSco() 进行完全相同的调用
10-03 17:01:01.689: D/AudioStateManager(29487): startBluetoothSco()
10-03 17:01:01.689: I/AudioStateManager(29487): mAudioManager.startBluetoothSco();
startBluetoothSco 的第一个结果出现在...
10-03 17:01:01.708: D/AudioStateManager(29487): onReceive: intent=Intent { act=android.media.ACTION_SCO_AUDIO_STATE_UPDATED flg=0x10 (has extras) }
10-03 17:01:01.712: D/AudioStateManager(29487): extras={"android.media.extra.SCO_AUDIO_STATE"=2, "android.media.extra.SCO_AUDIO_PREVIOUS_STATE"=0}
10-03 17:01:01.712: D/AudioStateManager(29487): android.media.ACTION_SCO_AUDIO_STATE_UPDATED
10-03 17:01:01.712: D/AudioStateManager(29487): ==> scoAudioStatePrevious=SCO_AUDIO_STATE_DISCONNECTED(0)
10-03 17:01:01.712: D/AudioStateManager(29487): ==> scoAudioState=SCO_AUDIO_STATE_CONNECTING(2)
...从 DISCONNECTED 移动到 CONNECTING
这是与在 17:00:37.626 自动调用 startBluetoothSco() 不同的地方
我们得到一个BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED事件...
10-03 17:01:01.716: D/AudioStateManager(29487): onReceive: intent=Intent { act=android.bluetooth.headset.profile.action.AUDIO_STATE_CHANGED flg=0x10 (has extras) }
10-03 17:01:01.720: D/AudioStateManager(29487): extras={"android.bluetooth.device.extra.DEVICE"=00:21:3C:00:3E:02, "android.bluetooth.profile.extra.PREVIOUS_STATE"=10, "android.bluetooth.profile.extra.STATE"=11}
10-03 17:01:01.720: D/AudioStateManager(29487): mReceiver: BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED
10-03 17:01:01.720: D/AudioStateManager(29487): ==> bluetoothDevice=00:21:3C:00:3E:02
10-03 17:01:01.720: D/AudioStateManager(29487): ==> bluetoothHeadsetAudioStatePrevious=STATE_AUDIO_DISCONNECTED(10)
10-03 17:01:01.720: D/AudioStateManager(29487): ==> bluetoothHeadsetAudioState=STATE_AUDIO_CONNECTING(11)
...从 DISCONNECTED 移动到 CONNECTING
我们得到另一个 BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED 事件...
10-03 17:01:02.572: D/AudioStateManager(29487): onReceive: intent=Intent { act=android.bluetooth.headset.profile.action.AUDIO_STATE_CHANGED flg=0x10 (has extras) }
10-03 17:01:02.576: D/AudioStateManager(29487): extras={"android.bluetooth.device.extra.DEVICE"=00:21:3C:00:3E:02, "android.bluetooth.profile.extra.PREVIOUS_STATE"=11, "android.bluetooth.profile.extra.STATE"=12}
10-03 17:01:02.576: D/AudioStateManager(29487): mReceiver: BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED
10-03 17:01:02.576: D/AudioStateManager(29487): ==> bluetoothDevice=00:21:3C:00:3E:02
10-03 17:01:02.576: D/AudioStateManager(29487): ==> bluetoothHeadsetAudioStatePrevious=STATE_AUDIO_CONNECTING(11)
10-03 17:01:02.580: D/AudioStateManager(29487): ==> bluetoothHeadsetAudioState=STATE_AUDIO_CONNECTED(12)
...从 CONNECTING 移动到 CONNECTED
事件使用一个 sendMessage 更新 UI
10-03 17:01:02.580: I/MainActivity(29487): onBluetoothHeadsetAudioConnected()
10-03 17:01:02.580: D/MainActivity(29487): MSG_UPDATE_BLUETOOTH_INDICATION
10-03 17:01:02.580: D/MainActivity(29487): updateScreen()...
10-03 17:01:02.583: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=true
... UI 更新完成(老实说,我不确定第二次调用 isBluetoothScoOn 是什么)
10-03 17:01:02.603: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=true
startBluetoothSco 的第二个结果进来......
10-03 17:01:02.603: D/AudioStateManager(29487): onReceive: intent=Intent { act=android.media.ACTION_SCO_AUDIO_STATE_UPDATED flg=0x10 (has extras) }
10-03 17:01:02.607: D/AudioStateManager(29487): extras={"android.media.extra.SCO_AUDIO_STATE"=1, "android.media.extra.SCO_AUDIO_PREVIOUS_STATE"=2}
10-03 17:01:02.607: D/AudioStateManager(29487): android.media.ACTION_SCO_AUDIO_STATE_UPDATED
10-03 17:01:02.607: D/AudioStateManager(29487): ==> scoAudioStatePrevious=SCO_AUDIO_STATE_CONNECTING(2)
10-03 17:01:02.607: D/AudioStateManager(29487): ==> scoAudioState=.SCO_AUDIO_STATE_CONNECTED(1)
10-03 17:01:02.607: D/AudioStateManager(29487): android.media.ACTION_SCO_AUDIO_STATE_UPDATED: SCO_AUDIO_STATE_CONNECTED
...从 CONNECTING 移动到 CONNECTED
最后!
我的事件侦听器被调用并使用两个 sendMessages 更新 UI ...
10-03 17:01:02.611: I/MainActivity(29487): onAudioManagerScoAudioConnected()
10-03 17:01:02.630: D/MainActivity(29487): MSG_UPDATE_BLUETOOTH_INDICATION
10-03 17:01:02.630: D/MainActivity(29487): updateScreen()...
10-03 17:01:02.634: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=true
10-03 17:01:02.650: D/MainActivity(29487): MSG_UPDATE_AUDIO_OUTPUT_STREAM_TYPE
10-03 17:01:02.650: D/MainActivity(29487): updateScreen()...
10-03 17:01:02.650: D/AudioStateManager(29487): mAudioManager.isBluetoothScoOn()=true
...UI 更新完成
当我在一段时间后“手动”启动 SCO 时,一切(这次)都可以工作,但如果我在连接耳机后立即自动启动 SCO,则不会。
更糟糕的是,当事情没有按预期工作时,我在 SCO 国家看到了奇怪的行为:
- 将 startBluetoothSco() 延迟 3-5 秒似乎没有什么区别。我没有尝试将其延迟超过 5 秒。等待 5 秒以上让音频开始流入您的 BT 耳机是荒谬的。
- 有时调用 isBluetoothScoOn() 会返回 true,即使自上次 DISCONNECTED 状态说状态更改为 CONNECTED 以来我从未收到过广播事件。
- 有时,从 UI 中“手动”调用 startBluetoothSco() 什么都不做,就好像 SCO 已经打开一样,但自从上次 DISCONNECTED 状态说状态更改为 CONNECTED 以来,我从未收到任何广播事件。
- 尝试打开 AudioTrack 或 AudioRecord 导致没有声音(当 SCO 没有异常行为时,同样的代码可以正常工作。即:问题是 SCO 状态,而不是 AudioTrack/AudioRecord 调用)。
- 调用 stopBluetoothSco() 不会导致任何事件报告状态 DISCONNECTED。
- setBluetoothScoOn(false/true) 没有区别。老实说,我不明白看似多余的“startBluetoothSco()/stopBluetoothSco()”和“setBluetoothScoOn(boolean)”的区别。当一切正常时,我调用 startBluetoothSco() 会导致 isBluetoothScoOn() 返回 true,这让我认为我不需要调用 setBluetoothScoOn(true)。
- 重新启动手机没有任何区别。
- 重新启动耳机没有任何区别。
- 换另一个耳机没什么区别。
- 有时耳机会失去配对,必须重新配对。
鉴于谷歌/Android 在蓝牙支持方面的记录,这很少让我感到惊讶。
有人可以让我摆脱痛苦并明确解释如何在Android中可靠地启动和停止蓝牙SCO吗?
PS:是否有官方渠道可以升级此类问题 [w/Google? 三星?]?或者,StackOverflow 是我找到实际答案的最佳机会吗?