Recording Video with AVFoundation in Swift for iOS - ios

Question

I am having trouble recording video using the code provided. I am using example code created for recording video.
Specifically I am unable to compile this line without this error: "Cannot convert value of type 'ViewController' to specified type 'AVCaptureFileOutputRecordingDelegate'
var recordingDelegate:AVCaptureFileOutputRecordingDelegate? = self
This line is located in a IBAction function:
#IBAction func RecordButtonPressed(_ sender: Any) {
var recordingDelegate:AVCaptureFileOutputRecordingDelegate? = self
var videoFileOutput = AVCaptureMovieFileOutput()
self.captureSession.addOutput(videoFileOutput)
let documentsURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
let filePath = documentsURL.appendingPathComponent("temp")
videoFileOutput.startRecording(toOutputFileURL: filePath, recordingDelegate: recordingDelegate)
RecordButton.setTitle("Stop", for: .normal);
}
Rest of code is here:
import UIKit
import AVFoundation
import Darwin
class ViewController: UIViewController {
#IBOutlet weak var CameraView: UIImageView!
#IBOutlet weak var RecordButton: UIButton!
#IBOutlet weak var SelectFrButton: UIButton!
#IBOutlet weak var ISOslider: UISlider!
#IBOutlet weak var SSslider: UISlider!
#IBOutlet weak var ISOtextfield: UITextField!
#IBOutlet weak var SStextfield: UITextField!
#IBOutlet weak var TorchSlider: UISlider!
#IBOutlet weak var Torchtextfield: UITextField!
var captureSession = AVCaptureSession();
var DisplaySessionOutput = AVCaptureVideoDataOutput();
var SaveSessionOutput = AVCaptureMovieFileOutput();
var previewLayer = AVCaptureVideoPreviewLayer();
var CaptureDevice:AVCaptureDevice? = nil;
var CurrentTorchLevel:Float = 0.5;
override func viewDidLoad() {
super.viewDidLoad()
captureSession.sessionPreset = AVCaptureSessionPresetHigh
// Loop through all the capture devices on this phone
let deviceDiscoverySession = AVCaptureDeviceDiscoverySession(deviceTypes: [AVCaptureDeviceType.builtInDuoCamera, AVCaptureDeviceType.builtInTelephotoCamera,AVCaptureDeviceType.builtInWideAngleCamera], mediaType: AVMediaTypeVideo, position: AVCaptureDevicePosition.unspecified)
for device in (deviceDiscoverySession?.devices)! {
if(device.position == AVCaptureDevicePosition.back){
do{
try device.lockForConfiguration()
device.setExposureModeCustomWithDuration(CMTimeMake(1, 30), iso: 50, completionHandler: { (time) in
// Set text and sliders to correct levels
self.ISOslider.maximumValue = (self.CaptureDevice?.activeFormat.maxISO)!;
self.ISOslider.minimumValue = (self.CaptureDevice?.activeFormat.minISO)!;
self.SSslider.maximumValue = Float((self.CaptureDevice?.activeFormat.maxExposureDuration.seconds)!);
self.SSslider.minimumValue = Float((self.CaptureDevice?.activeFormat.minExposureDuration.seconds)!);
self.ISOtextfield.text = device.iso.description;
self.ISOslider.setValue(device.iso, animated: false)
self.SStextfield.text = device.exposureDuration.seconds.description;
self.SSslider.setValue(Float(device.exposureDuration.seconds), animated: false);
self.TorchSlider.minimumValue = 0.01;
self.TorchSlider.maximumValue = 1;
self.TorchSlider.value = 0.5;
self.Torchtextfield.text = "0.5";
})
//Turn torch on
if (device.torchMode == AVCaptureTorchMode.on) {
device.torchMode = AVCaptureTorchMode.off
} else {
try device.setTorchModeOnWithLevel(1.0)
}
device.unlockForConfiguration();
CaptureDevice = device;
let input = try AVCaptureDeviceInput(device: CaptureDevice)
if(captureSession.canAddInput(input)){
captureSession.addInput(input);
if(captureSession.canAddOutput(DisplaySessionOutput)){
captureSession.addOutput(DisplaySessionOutput);
previewLayer = AVCaptureVideoPreviewLayer(session: captureSession);
previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
previewLayer.connection.videoOrientation = AVCaptureVideoOrientation.portrait;
CameraView.layer.addSublayer(previewLayer);
}
}
}
catch{
print("exception!");
}
}
}
CameraView.transform = CGAffineTransform.init(scaleX: -1, y: -1);
captureSession.startRunning()
}
// Do any additional setup after loading the view, typically from a nib.
override func viewDidLayoutSubviews() {
previewLayer.frame = CameraView.bounds
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func RecordButtonPressed(_ sender: Any) {
var recordingDelegate:AVCaptureFileOutputRecordingDelegate? = self
var videoFileOutput = AVCaptureMovieFileOutput()
self.captureSession.addOutput(videoFileOutput)
let documentsURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
let filePath = documentsURL.appendingPathComponent("temp")
videoFileOutput.startRecording(toOutputFileURL: filePath, recordingDelegate: recordingDelegate)
RecordButton.setTitle("Stop", for: .normal);
}
#IBAction func ISOvaluechanged(_ sender: Any) {
SetVideoSettings(isolevel: ISOslider.value, exposurelevel: AVCaptureExposureDurationCurrent, TorchLevel: CurrentTorchLevel)
}
#IBAction func SSvaluechanged(_ sender: Any) {
let time = CMTimeMake(Int64(self.SSslider.value * 1000000),1000000);
SetVideoSettings(isolevel: AVCaptureISOCurrent, exposurelevel: time, TorchLevel: CurrentTorchLevel)
}
#IBAction func ISOtextchanged(_ sender: Any) {
}
#IBAction func SStextchanged(_ sender: Any) {
//let time = CMTimeMake(Int64(exposurelevel * 100000),100000);
}
#IBAction func ChooseButtonPressed(_ sender: Any) {
}
func ShowAlert(AlertMessage: String) {
let alertController = UIAlertController(title: "Alert", message: AlertMessage, preferredStyle: .alert)
self.present(alertController, animated: true, completion:nil)
let OKAction = UIAlertAction(title: "OK", style: .default) { (action:UIAlertAction) in
}
alertController.addAction(OKAction)
}
#IBAction func TorchSliderChanged(_ sender: Any) {
CurrentTorchLevel = self.TorchSlider.value;
SetVideoSettings(isolevel: AVCaptureISOCurrent, exposurelevel: AVCaptureExposureDurationCurrent, TorchLevel: CurrentTorchLevel);
}
func SetVideoSettings(isolevel: Float, exposurelevel: CMTime, TorchLevel: Float) {
var newISOval = isolevel;
var newSSval = exposurelevel;
let newTorchVal = TorchLevel;
if(newISOval == FLT_MAX){
// Pass through 0,0 for maintaining current SS.
}
else if(newISOval > (self.CaptureDevice?.activeFormat.maxISO)!) {
newISOval = (self.CaptureDevice?.activeFormat.maxISO)!;
}
else if(newISOval < (self.CaptureDevice?.activeFormat.minISO)!) {
newISOval = (self.CaptureDevice?.activeFormat.minISO)!;
}
if(newSSval.timescale == 0){
// Pass through 0,0 for maintaining current SS.
}
else if(CMTimeCompare(newSSval, (self.CaptureDevice?.activeFormat.maxExposureDuration)!) > 0) {
newSSval = (self.CaptureDevice?.activeFormat.maxExposureDuration)!;
}
else if(CMTimeCompare(newSSval,(self.CaptureDevice?.activeFormat.minExposureDuration)!) < 0) {
newSSval = (self.CaptureDevice?.activeFormat.minExposureDuration)!;
}
do {
try self.CaptureDevice?.lockForConfiguration();
try CaptureDevice?.setTorchModeOnWithLevel(newTorchVal);
CaptureDevice?.setExposureModeCustomWithDuration(newSSval, iso: newISOval, completionHandler: { (time) in
// Set text and sliders to correct levels
self.ISOtextfield.text = self.CaptureDevice?.iso.description;
self.ISOslider.setValue((self.CaptureDevice?.iso)!, animated: false)
self.SStextfield.text = self.CaptureDevice?.exposureDuration.seconds.description;
self.SSslider.setValue(Float((self.CaptureDevice?.exposureDuration.seconds)!), animated: false);
self.TorchSlider.setValue(self.CurrentTorchLevel, animated: false);
self.Torchtextfield.text = self.CurrentTorchLevel.description;
})
self.CaptureDevice?.unlockForConfiguration();
}
catch {
ShowAlert(AlertMessage: "Unable to set camera settings");
self.CaptureDevice?.unlockForConfiguration();
}
}
func captureOutput(captureOutput: AVCaptureFileOutput!, didFinishRecordingToOutputFileAtURL outputFileURL: NSURL!, fromConnections connections: [AnyObject]!, error: NSError!) {
return
}
func captureOutput(captureOutput: AVCaptureFileOutput!, didStartRecordingToOutputFileAtURL fileURL: NSURL!, fromConnections connections: [AnyObject]!) {
return
}
}
Thank you for any help you can provide!

Answer 1

Make an extension for your UIViewController that makes it conform to AVCaptureFileOutputRecordingDelegate. Remove and add the final two methods in your ViewController class into it.
class ViewController:UIViewController {
//your methods as usual but remove the final two methods and add them to the extension that follows. Those methods are what will make you conform to AVCaptureFileOutputRecordingDelegate
}
extension ViewController: AVCaptureFileOutputRecordingDelegate {
func capture(_ captureOutput: AVCaptureFileOutput!, didStartRecordingToOutputFileAt fileURL: URL!, fromConnections connections: [Any]!) {
}
func capture(_ captureOutput: AVCaptureFileOutput!, didFinishRecordingToOutputFileAt outputFileURL: URL!, fromConnections connections: [Any]!, error: Error!) {
}
}
You can do the same thing by extending your UIViewController as below but I thought I'd give you a clean solution as above. You can choose.
class ViewController:UIViewController, AVCaptureFileOutputRecordingDelegate {
//your methods as usual but you keep your final two methods this time
func capture(_ captureOutput: AVCaptureFileOutput!, didStartRecordingToOutputFileAt fileURL: URL!, fromConnections connections: [Any]!) {
}
func capture(_ captureOutput: AVCaptureFileOutput!, didFinishRecordingToOutputFileAt outputFileURL: URL!, fromConnections connections: [Any]!, error: Error!) {
}
}