AVAudioSession.setCateogry 没有蓝牙麦克风输入

Question

我正在尝试使用录音机来捕获来自 AirPods Pro 的输入。以下函数执行音频捕获，它适用于内置麦克风，但不适用于 AirPods。这个问题在模拟器和真实设备上都存在。有人可以指出我在这里缺少什么来启用蓝牙捕获吗？谢谢！

func startRecording() {
        let recordingSession = AVAudioSession.sharedInstance()
        
        // Then we start recording session with
        do {
            try recordingSession.setCategory(.playAndRecord, mode: .default, options: [.allowBluetooth, .defaultToSpeaker, .allowBluetoothA2DP])
            try recordingSession.setActive(true)
        } catch {
            print("Failed to set up recording session")
            
        }
        
        // Then we say where to save it
        let documentPath = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
        
        // file is named after the date and time of the recording in the .m4a format.
        let audioFilename = documentPath.appendingPathComponent("\(Date().toString( dateFormat: "dd-MM-YY_'at'_HH:mm:ss")).m4a")
        
        let settings = [
                    AVFormatIDKey: Int(kAudioFormatLinearPCM),
                    AVSampleRateKey: 48000,
                    AVNumberOfChannelsKey: 1,
                    AVEncoderAudioQualityKey: AVAudioQuality.high.rawValue
                ]
        
        do {
            audioRecorder = try AVAudioRecorder(url: audioFilename, settings: settings)
            audioRecorder.record()
            recording = true
        } catch {
            print("Could not start recording")
        }
    } //end func startRecording

Answer 1

试试这个：

    audioRecorder = try AVAudioRecorder(url: audioFilename, settings: settings)
    audioRecorder.prepareToRecord()
    audioRecorder.record()

Answer 2

您的问题出在您的选项中：[.allowBluetooth, .defaultToSpeaker, .allowBluetoothA2DP]。 A2DP 不支持录音，因此当您将设备置于 A2DP 模式时，其麦克风将被禁用。您需要删除 .allowBluetoothA2DP 选项

请注意，当您执行此操作时，它会切换到 HFP 模式（这就是 .allowBluetooth 的实际含义）。这将显着降低音频输出。对于录音机，这可能没问题，但如果您在播放高质量音频的同时尝试从 AirPod 的麦克风录音，则不支持。

AVAudioSession.setCateogry 没有蓝牙麦克风输入

No bluetooth mic input with AVAudioSession.setCateogry

xcode

avfoundation

swift