Video recording has no Audio?

Question

I have made a successful video recording program, but it has no audio? What should I do to fix this? I have the audio permissions properly set up in my info.plist. I am using the AVCaptureFileOutputRecordingDelegate.

 override func viewWillAppear(_ animated: Bool) {
      let deviceDiscoverySession = AVCaptureDeviceDiscoverySession(deviceTypes: [AVCaptureDeviceType.builtInDuoCamera, AVCaptureDeviceType.builtInTelephotoCamera,AVCaptureDeviceType.builtInWideAngleCamera], mediaType: AVMediaTypeVideo, position: AVCaptureDevicePosition.back)

    for device in (deviceDiscoverySession?.devices)!{
        if(device.position == AVCaptureDevicePosition.back){

            do{
                let input = try AVCaptureDeviceInput(device: device )

                if captureSession.canAddInput(input){

                    captureSession.addInput(input)

                }

               // sessionOutput.videoSettings = [(kCVPixelBufferPixelFormatTypeKey as NSString) : NSNumber(value: kCVPixelFormatType_420YpCbCr8BiPlanarFullRange as UInt32)]

                sessionOutput.alwaysDiscardsLateVideoFrames = true

                if(captureSession.canAddOutput(sessionOutput) == true){
                    captureSession.addOutput(sessionOutput)

                    let previewLayer: AVCaptureVideoPreviewLayer = {
                        let preview =  AVCaptureVideoPreviewLayer(session: self.captureSession)
                        preview?.bounds = CGRect(x: 0, y: 0, width: self.view.bounds.width, height: self.view.bounds.height)
                        preview?.position = CGPoint(x: self.view.bounds.midX, y: self.view.bounds.midY)
                        preview?.videoGravity = AVLayerVideoGravityResize
                        return preview!
                    }()

                    view.layer.insertSublayer(previewLayer, at: 0)

                    output = AVCaptureMovieFileOutput()
                    let maxDuration = CMTimeMakeWithSeconds(180, 30)
                    output.maxRecordedDuration = maxDuration
                    captureSession.addOutput(output)



                }

                captureSession.commitConfiguration()

            }

            catch{
                print("Error")
            }


        }

    }

I have tried the solution posted here but all it did was mess up what I already had working with the camera. Any guidance is appreciated!

Answer 1

Simple steps, to implement as you want:

1. Get your capture device for video (AVMediaTypeVideo)
2. Get your capture device for audio (AVMediaTypeAudio)
3. Create your video input (AVCaptureDeviceInput with video device)
4. Create your audio input (AVCaptureDeviceInput with audio device)
5. Configure your capture session (AVCaptureSession) via beginConfiguration()
6. Add Inputs to capture session via addInput()
7. Commit configuration via commitConfiguration()

Answer 2

After adding audio input if you are still facing missing audio issues after some record duration. use this code. It worked for me.

videoOutput?.movieFragmentInterval = .invalid