ios - 观看视频时录制视频并带有音频

Question

当用户同时观看视频时，我尝试从前置摄像头录制视频。如果没有音频输入，源代码就像一个魅力，但是当我激活音频输入时，视频不会开始播放。这是可能的还是我正在尝试实现不可能的目标？

录制视频源代码

override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)

        self.session.beginConfiguration()
        self.session.sessionPreset = AVCaptureSessionPresetMedium

        // Add video input.
        do {
            guard let videoDevice = AVCaptureDevice.defaultDevice(withDeviceType: .builtInWideAngleCamera, mediaType: AVMediaTypeVideo, position: .front) else {fatalError()}
            let videoDeviceInput = try AVCaptureDeviceInput(device: videoDevice)

            if self.session.canAddInput(videoDeviceInput) {
                self.session.addInput(videoDeviceInput)
            } else {
                print("Could not add video device input to the session")
                self.session.commitConfiguration()
                return
            }
        } catch {
            print("Could not create video device input: \(error)")
            self.session.commitConfiguration()
            return
        }

        // Add audio input.
        do {
            guard let audioDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeAudio) else {fatalError()}
            let audioDeviceInput = try AVCaptureDeviceInput(device: audioDevice)

            if self.session.canAddInput(audioDeviceInput) {
                self.session.addInput(audioDeviceInput)
            }
            else {
                print("Could not add audio device input to the session")
            }
        } catch {
            print("Could not create audio device input: \(error)")
        }

        self.videoPreviewLayer = AVCaptureVideoPreviewLayer(session: self.session)
        self.videoPreviewLayer!.videoGravity = AVLayerVideoGravityResizeAspect
        self.videoPreviewLayer!.connection?.videoOrientation = AVCaptureVideoOrientation.portrait
        self.cameraElement.layer.addSublayer(self.videoPreviewLayer!)
        self.session.commitConfiguration()
        self.session.startRunning()
}

func startRecording() {
    let recordingDelegate: AVCaptureFileOutputRecordingDelegate? = self
    self.videoFileOutput = AVCaptureMovieFileOutput()
    self.session.addOutput(videoFileOutput)

    let filePath = NSURL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent("tmpVideo.mov")
    ContentController.tmpFilePath = filePath
    videoFileOutput?.startRecording(toOutputFileURL: filePath, recordingDelegate: recordingDelegate)

}

播放视频源代码

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)

    player = AVPlayer(url: ContentController.content!.url!)
    let playerLayer: AVPlayerLayer = AVPlayerLayer(player: player)
    playerLayer.frame = self.videoElement.bounds
    self.videoElement.layer.addSublayer(playerLayer)

    player?.currentItem!.addObserver(self, forKeyPath: "status", options: NSKeyValueObservingOptions(), context: nil)
}

Answer 1

问题出在线程处理上。

我的解决方案是:

func playerReadyToPlay() {
    DispatchQueue.global(qos: .userInitiated).async {
        self.player?.play()
    }
    super.startRecording()
}