使用 AVAudioRecorder 录制 Opus iOS

Question

我正在尝试以 iOS 格式录制 Opus 格式。当我使用 LinearPCM 格式测试记录器时，即 wav、AVAudioRecorderDelegate 函数和 updateMeters 被正确调用并且记录器 url 将有效文件保存在给定路径。这是我用于重新编码的配置。

let fileMgr = FileManager.default
let dirPaths = fileMgr.urls(for: .documentDirectory,
                                in: .userDomainMask)
let soundFileURL = dirPaths[0].appendingPathComponent("audio.wav")
let recordSettings =
        [AVEncoderAudioQualityKey: AVAudioQuality.low.rawValue,
         AVEncoderBitRateKey: 16,
         AVNumberOfChannelsKey: 1,
         AVFormatIDKey : kAudioFormatLinearPCM,
         AVSampleRateKey: 44100.0] as [String : Any]

然后我尝试使用以下配置对 Opus 进行测试，但未调用委托函数，仪表值常量 -160db（无声）并且 audioRecorder url 为 nil因为我无法在委托函数中获取它：

func audioRecorderDidFinishRecording(_ recorder: AVAudioRecorder, successfully flag: Bool) {
    print(audioRecorder!.currentTime)
    self.audioFileUrl = audioRecorder!.url
}

我正在使用的 Opus 配置：

let soundFileURL = dirPaths[0].appendingPathComponent("audio.opus")
    let recordSettings =
        [AVEncoderAudioQualityKey: AVAudioQuality.high.rawValue,
         AVEncoderBitRateKey: 16,
         AVNumberOfChannelsKey: 1,
         AVFormatIDKey : kAudioFormatOpus,
         AVSampleRateKey: 44100.0] as [String : Any]

如何正确设置配置以录制我的音频社交网络应用程序的 Opus 格式。在其他用户端上传和收听 30 秒音频帖子的最佳方式是什么。

Answer 1

试试这个：

var recordSettings = Dictionary() as [String: Any]
var audioRecorder: AVAudioRecorder?

func recordAudio() {
    let fileMgr = FileManager.default
    let dirPaths = fileMgr.urls(for: .documentDirectory,
                                in: .userDomainMask)
    let soundFileURL = dirPaths[0].appendingPathComponent("audio.wav")
    recordSettings =
        [AVEncoderAudioQualityKey: AVAudioQuality.low.rawValue,
         AVEncoderBitRateKey: 16,
         AVNumberOfChannelsKey: 1,
         AVFormatIDKey : kAudioFormatLinearPCM,
         AVSampleRateKey: 44100.0] as [String : Any]

    do {
        audioRecorder = try AVAudioRecorder(url: soundFileURL, settings: recordSettings)
    } catch {
        print(error.localizedDescription)
    }

    audioRecorder?.delegate = self
    audioRecorder?.prepareToRecord()

    // call record method when you want to start recording
    audioRecorder?.record()
}

func audioRecorderDidFinishRecording(_ recorder: AVAudioRecorder, successfully flag: Bool) {

    print(recorder.currentTime)
    do {
        audioPlayer = try AVAudioPlayer(contentsOf: recorder.url)
    } catch {
        print(error)
    }
    audioPlayer?.play()
}

您需要在停止录制时调用audioRecorder?.stop()。它会在 audioRecorderDidFinishRecording(_ recorder: 方法中给你回调。希望对你有帮助。

Answer 2

以下用于重新编码 Opus 格式的配置有效。它不适用于 44100 Hz。仅适用于 16000 或 24000 Hz。

let recordSettings =
        [AVNumberOfChannelsKey: 1,
         AVFormatIDKey : kAudioFormatOpus,
         AVSampleRateKey: 24000.0] as [String : Any]

没有其他变化，文件被正确保存，现在也调用了 didFinishRecoding。

使用 AVAudioRecorder 录制 Opus iOS

Record Opus with AVAudioRecorder iOS

audio-recording

ios

opus

swift