在Swift中录制音频

Question

有谁知道我在哪里可以找到有关如何在Swift应用程序中录制音频的信息？我一直在看一些音频播放示例,但我似乎无法找到任何实现录音的内容.谢谢

Answer 1

这是代码.你可以轻松录制.写上这段代码.IBAction它将Documents按名称保存录音recordTest.caf

//declare instance variable 
var audioRecorder:AVAudioRecorder!
func record(){        
    var audioSession:AVAudioSession = AVAudioSession.sharedInstance()
    audioSession.setCategory(AVAudioSessionCategoryPlayAndRecord, error: nil)
    audioSession.setActive(true, error: nil)

    var documents: AnyObject = NSSearchPathForDirectoriesInDomains( NSSearchPathDirectory.DocumentDirectory,  NSSearchPathDomainMask.UserDomainMask, true)[0]
    var str =  documents.stringByAppendingPathComponent("recordTest.caf")
    var url = NSURL.fileURLWithPath(str as String)

    var recordSettings = [AVFormatIDKey:kAudioFormatAppleIMA4,
        AVSampleRateKey:44100.0,
        AVNumberOfChannelsKey:2,AVEncoderBitRateKey:12800,
        AVLinearPCMBitDepthKey:16,
        AVEncoderAudioQualityKey:AVAudioQuality.Max.rawValue]

    println("url : \(url)")
    var error: NSError?

    audioRecorder = AVAudioRecorder(URL:url, settings: recordSettings, error: &error)
    if let e = error {
        println(e.localizedDescription)
    } else {
        audioRecorder.record()
    }        
}

Answer 2

在Swift 3中

• 添加框架AVFoundation
• 在info.plist中添加密钥:隐私 - 麦克风使用说明和值:使用麦克风(如果您不提供值,应用程序将崩溃 - 描述您要求获得权限的原因)

• 导入AVFoundation和AVAudioRecorderDelegate,AVAudioPlayerDelegate

  import AVFoundation
  
   class RecordVC: UIViewController , AVAudioRecorderDelegate, AVAudioPlayerDelegate
  

• 创建用于录制音频和播放音频的按钮,并标记显示录制时间并提供出口和操作作为start_recording,play_recording并声明一些我们稍后将使用的变量

  @IBOutlet var recordingTimeLabel: UILabel!
  @IBOutlet var record_btn_ref: UIButton!
  @IBOutlet var play_btn_ref: UIButton!
  
  var audioRecorder: AVAudioRecorder!
  var audioPlayer : AVAudioPlayer!
  var meterTimer:Timer!
  var isAudioRecordingGranted: Bool!
  var isRecording = false
  var isPlaying = false
  

• 在viewDidLoad中检查记录权限

  override func viewDidLoad() {
      super.viewDidLoad()
      check_record_permission()
  }
  
  func check_record_permission()
  {
      switch AVAudioSession.sharedInstance().recordPermission() {
      case AVAudioSessionRecordPermission.granted:
          isAudioRecordingGranted = true
          break
      case AVAudioSessionRecordPermission.denied:
          isAudioRecordingGranted = false
          break
      case AVAudioSessionRecordPermission.undetermined:
          AVAudioSession.sharedInstance().requestRecordPermission({ (allowed) in
                  if allowed {
                      self.isAudioRecordingGranted = true
                  } else {
                      self.isAudioRecordingGranted = false
                  }
          })
          break
      default:
          break
      }
  }
  

• 生成要将该录制保存为myRecording.m4a的路径

  func getDocumentsDirectory() -> URL
  {
      let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
      let documentsDirectory = paths[0]
      return documentsDirectory
  }
  
  func getFileUrl() -> URL
  {
      let filename = "myRecording.m4a"
      let filePath = getDocumentsDirectory().appendingPathComponent(filename)
  return filePath
  }
  

• 设置录像机

  func setup_recorder()
  {
      if isAudioRecordingGranted
      {
          let session = AVAudioSession.sharedInstance()
          do
          {
              try session.setCategory(AVAudioSessionCategoryPlayAndRecord, with: .defaultToSpeaker)
              try session.setActive(true)
              let settings = [
                  AVFormatIDKey: Int(kAudioFormatMPEG4AAC),
                  AVSampleRateKey: 44100,
                  AVNumberOfChannelsKey: 2,
                  AVEncoderAudioQualityKey:AVAudioQuality.high.rawValue
              ]
              audioRecorder = try AVAudioRecorder(url: getFileUrl(), settings: settings)
              audioRecorder.delegate = self
              audioRecorder.isMeteringEnabled = true
              audioRecorder.prepareToRecord()
          }
          catch let error {
              display_alert(msg_title: "Error", msg_desc: error.localizedDescription, action_title: "OK")
          }
      }
      else
      {
          display_alert(msg_title: "Error", msg_desc: "Don't have access to use your microphone.", action_title: "OK")
      }
  }
  

• 当按钮start_recording按下并使用updateAudioMeter显示秒时开始录制,如果录制开始则完成录制

  @IBAction func start_recording(_ sender: UIButton)
  {
      if(isRecording)
      {
          finishAudioRecording(success: true)
          record_btn_ref.setTitle("Record", for: .normal)
          play_btn_ref.isEnabled = true
          isRecording = false
      }
      else
      {
          setup_recorder()
  
          audioRecorder.record()
          meterTimer = Timer.scheduledTimer(timeInterval: 0.1, target:self, selector:#selector(self.updateAudioMeter(timer:)), userInfo:nil, repeats:true)
          record_btn_ref.setTitle("Stop", for: .normal)
          play_btn_ref.isEnabled = false
          isRecording = true
      }
  }
  
  func updateAudioMeter(timer: Timer)
  {
      if audioRecorder.isRecording
      {
          let hr = Int((audioRecorder.currentTime / 60) / 60)
          let min = Int(audioRecorder.currentTime / 60)
          let sec = Int(audioRecorder.currentTime.truncatingRemainder(dividingBy: 60))
          let totalTimeString = String(format: "%02d:%02d:%02d", hr, min, sec)
          recordingTimeLabel.text = totalTimeString
          audioRecorder.updateMeters()
      }
  }
  
  func finishAudioRecording(success: Bool)
  {
      if success
      {
          audioRecorder.stop()
          audioRecorder = nil
          meterTimer.invalidate()
          print("recorded successfully.")
      }
      else
      {
          display_alert(msg_title: "Error", msg_desc: "Recording failed.", action_title: "OK")
      }
  }
  

• 播放录音

  func prepare_play()
  {
      do
      {
          audioPlayer = try AVAudioPlayer(contentsOf: getFileUrl())
          audioPlayer.delegate = self
          audioPlayer.prepareToPlay()
      }
      catch{
          print("Error")
      }
  }
  
  @IBAction func play_recording(_ sender: Any)
  {
      if(isPlaying)
      {
          audioPlayer.stop()
          record_btn_ref.isEnabled = true
          play_btn_ref.setTitle("Play", for: .normal)
          isPlaying = false
      }
      else
      {
          if FileManager.default.fileExists(atPath: getFileUrl().path)
          {
              record_btn_ref.isEnabled = false
              play_btn_ref.setTitle("pause", for: .normal)
              prepare_play()
              audioPlayer.play()
              isPlaying = true
          }
          else
          {
              display_alert(msg_title: "Error", msg_desc: "Audio file is missing.", action_title: "OK")
          }
      }
  }
  

• 录制完成后启用播放按钮,播放完成后启用录制按钮

  func audioRecorderDidFinishRecording(_ recorder: AVAudioRecorder, successfully flag: Bool)
  {
      if !flag
      {
          finishAudioRecording(success: false)
      }
      play_btn_ref.isEnabled = true
  }
  
  func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool)
  {
      record_btn_ref.isEnabled = true
  }
  

• 用于显示警报的通用功能

  func display_alert(msg_title : String , msg_desc : String ,action_title : String)
  {
      let ac = UIAlertController(title: msg_title, message: msg_desc, preferredStyle: .alert)
      ac.addAction(UIAlertAction(title: action_title, style: .default)
      {
          (result : UIAlertAction) -> Void in
      _ = self.navigationController?.popViewController(animated: true)
      })
      present(ac, animated: true)
  }
  

Answer 3

Swift2版@ codester的回答.

func record() {
    //init
    let audioSession:AVAudioSession = AVAudioSession.sharedInstance()

    //ask for permission
    if (audioSession.respondsToSelector("requestRecordPermission:")) {
        AVAudioSession.sharedInstance().requestRecordPermission({(granted: Bool)-> Void in
            if granted {
                print("granted")

                //set category and activate recorder session
                try! audioSession.setCategory(AVAudioSessionCategoryPlayAndRecord)
                try! audioSession.setActive(true)


                //get documnets directory
                let documentsDirectory = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0]
                let fullPath = documentsDirectory.stringByAppendingPathComponent("voiceRecording.caf")
                let url = NSURL.fileURLWithPath(fullPath)

                //create AnyObject of settings
                let settings: [String : AnyObject] = [
                    AVFormatIDKey:Int(kAudioFormatAppleIMA4), //Int required in Swift2
                    AVSampleRateKey:44100.0,
                    AVNumberOfChannelsKey:2,
                    AVEncoderBitRateKey:12800,
                    AVLinearPCMBitDepthKey:16,
                    AVEncoderAudioQualityKey:AVAudioQuality.Max.rawValue
                ]

                //record
                try! self.audioRecorder = AVAudioRecorder(URL: url, settings: settings)

            } else{
                print("not granted")
            }
        })
    }

}

Answer 4

除了之前的答案,我试图让它在Xcode 7.2上工作,之后我听不到任何声音,也不是在我通过电子邮件发送文件时.没有警告或例外.所以我将设置更改为以下内容并存储为.m4a文件.

let recordSettings = [AVSampleRateKey : NSNumber(float: Float(44100.0)),
    AVFormatIDKey : NSNumber(int: Int32(kAudioFormatMPEG4AAC)),
    AVNumberOfChannelsKey : NSNumber(int: 1),
    AVEncoderAudioQualityKey : NSNumber(int: Int32(AVAudioQuality.Medium.rawValue))]

之后,我可以听声音.为了保存文件,我在viewDidLoad上添加了这个来初始化记录器:

let audioSession = AVAudioSession.sharedInstance()
    do {
        try audioSession.setCategory(AVAudioSessionCategoryPlayAndRecord)
        try audioRecorder = AVAudioRecorder(URL: self.directoryURL()!,
            settings: recordSettings)
        audioRecorder.prepareToRecord()
    } catch {
    }

并且用于创建目录:

func directoryURL() -> NSURL? {
    let fileManager = NSFileManager.defaultManager()
    let urls = fileManager.URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)
    let documentDirectory = urls[0] as NSURL
    let soundURL = documentDirectory.URLByAppendingPathComponent("sound.m4a")
    return soundURL 
}

我还添加了用于开始录制,停止和播放的操作

@IBAction func doRecordAction(sender: AnyObject) {
    if !audioRecorder.recording {
        let audioSession = AVAudioSession.sharedInstance()
        do {
            try audioSession.setActive(true)
            audioRecorder.record()
        } catch {
        }
   }
}
@IBAction func doStopRecordingAction(sender: AnyObject) {
    audioRecorder.stop()
    let audioSession = AVAudioSession.sharedInstance()

    do {
        try audioSession.setActive(false)
    } catch {
    }
}

@IBAction func doPlayAction(sender: AnyObject) {
    if (!audioRecorder.recording){
        do {
            try audioPlayer = AVAudioPlayer(contentsOfURL: audioRecorder.url)
            audioPlayer.play()
        } catch {
        }
    }
}

Answer 5

这里是在 Swift 4.2 上编写的具有简单界面的录音机。

final class AudioRecorderImpl: NSObject {
  private let session = AVAudioSession.sharedInstance()
  private var player: AVAudioPlayer?
  private var recorder: AVAudioRecorder?
  private lazy var permissionGranted = false
  private lazy var isRecording = false
  private lazy var isPlaying = false
  private var fileURL: URL?
  private let settings = [
    AVFormatIDKey: Int(kAudioFormatMPEG4AAC),
    AVSampleRateKey: 44100,
    AVNumberOfChannelsKey: 2,
    AVEncoderAudioQualityKey:AVAudioQuality.high.rawValue
  ]

  override init() {
    fileURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first?.appendingPathComponent("note.m4a")
  }

  func record(to url: URL?) {
    guard permissionGranted,
      let url = url ?? fileURL else { return }

    setupRecorder(url: url)

    if isRecording {
      stopRecording()
    }

    isRecording = true
    recorder?.record()
  }

  func stopRecording() {
    isRecording = false
    recorder?.stop()
    try? session.setActive(false)
  }

  func play(from url: URL?) {
    guard let url = url ?? fileURL else { return }

    setupPlayer(url: url)

    if isRecording {
      stopRecording()
    }

    if isPlaying {
      stopPlaying()
    }

    if FileManager.default.fileExists(atPath: url.path) {
      isPlaying = true
      setupPlayer(url: url)
      player?.play()
    }
  }

  func stopPlaying() {
    player?.stop()
  }

  func pause() {
    player?.pause()
  }

  func resume() {
    if player?.isPlaying == false {
      player?.play()
    }
  }

  func checkPermission(completion: ((Bool) -> Void)?) {
    func assignAndInvokeCallback(_ granted: Bool) {
      self.permissionGranted = granted
      completion?(granted)
    }

    switch session.recordPermission {
    case .granted:
      assignAndInvokeCallback(true)

    case .denied:
      assignAndInvokeCallback(false)

    case .undetermined:
      session.requestRecordPermission(assignAndInvokeCallback)
    }
  }
}

extension AudioRecorderImpl: AVAudioRecorderDelegate, AVAudioPlayerDelegate {

}

private extension AudioRecorderImpl {
  func setupRecorder(url: URL) {
    guard
      permissionGranted else { return }
    try? session.setCategory(.playback, mode: .default)
    try? session.setActive(true)
    let settings = [
      AVFormatIDKey: Int(kAudioFormatMPEG4AAC),
      AVSampleRateKey: 44100,
      AVNumberOfChannelsKey: 2,
      AVEncoderAudioQualityKey: AVAudioQuality.high.rawValue
    ]
    recorder = try? AVAudioRecorder(url: url, settings: settings)
    recorder?.delegate = self
    recorder?.isMeteringEnabled = true
    recorder?.prepareToRecord()
  }

  func setupPlayer(url: URL) {
    player = try? AVAudioPlayer(contentsOf: url)
    player?.delegate = self
    player?.prepareToPlay()
  }
}