Camera Preview Layer not Loading - ios

Question

I am attempting to make a video preview layer and it seems to be working but nothing is showing up on the screen. Here is the code I used:
var captureSession = AVCaptureSession()
var backCamera: AVCaptureDevice?
var frontCamera: AVCaptureDevice?
var currentCamera: AVCaptureDevice?
var photoOutput: AVCapturePhotoOutput?
var cameraPreviewLayer: AVCaptureVideoPreviewLayer?
//UIOutlets
#IBOutlet weak var cameraView: UIView!
#IBOutlet weak var captureImageView: UIImageView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view
self.cameraSetupSession()
self.setupDevice()
self.setupInputOutput()
self.setupPerviewLayer()
self.startRunningCaptureSession()
}
func cameraSetupSession() {
print("1")
captureSession.sessionPreset = AVCaptureSession.Preset.photo
}
func setupDevice() {
print("2")
let deviceDiscoverySession = AVCaptureDevice.DiscoverySession(deviceTypes: [AVCaptureDevice.DeviceType.builtInWideAngleCamera], mediaType: .video , position: .unspecified)
let devices = deviceDiscoverySession.devices
for device in devices{
if device.position == .back{
backCamera = device
}else if device.position == .front{
frontCamera = device
}
}
currentCamera = backCamera
}
func setupInputOutput() {
print("3")
do{
let captureDeviceInput = try AVCaptureDeviceInput(device: currentCamera!)
captureSession.addInput(captureDeviceInput)
photoOutput?.setPreparedPhotoSettingsArray([AVCapturePhotoSettings(format:[AVVideoCodecKey:AVVideoCodecType.jpeg])], completionHandler: nil)
}catch{
displayAlert(title: "Error", message: "There was an error acseesing your camera feed.", okMessage: "Okay")
}
}
func setupPerviewLayer() {
print("4")
cameraPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
cameraPreviewLayer?.videoGravity = .resizeAspectFill
cameraPreviewLayer?.masksToBounds = true
cameraPreviewLayer?.connection?.videoOrientation = .portrait
self.view.layer.insertSublayer(cameraPreviewLayer!, at: 0)
}
func startRunningCaptureSession() {
print("5")
self.captureSession.startRunning()
print(self.captureSession.isRunning)
}`
My log output during this is:
1
2
2017-11-23 12:36:04.042296-0500 Instagram Clone[353:15568] [MC] System group container for systemgroup.com.apple.configurationprofiles path is /private/var/containers/Shared/SystemGroup/systemgroup.com.apple.configurationprofiles
2017-11-23 12:36:04.043014-0500 Instagram Clone[353:15568] [MC] Reading from public effective user settings.
3
4
5
true
One of the only positive signs I have is that it does ask permission to use the camera when I Delete and clean the app. Please, any and all ideas and help are very much appreciated.

Answer 1

Looking at the code the one thing I can see missing is you aren't linking the session to the preview layer.
Try adding the following to setupPerviewLayer()
cameraPreviewLayer?.session = captureSession

Answer 2

I took your code and changed some parts until work. And it works now. Here is your code.
import UIKit
import AVFoundation
import CoreVideo
class ViewController: UIViewController {
#IBOutlet var recordButton: UIButton!
var windowOrientation: UIInterfaceOrientation {
return view.window?.windowScene?.interfaceOrientation ?? .unknown
}
var captureSession = AVCaptureSession()
var backCamera: AVCaptureDevice?
var frontCamera: AVCaptureDevice?
var currentCamera: AVCaptureDevice?
var videoOutput = AVCaptureVideoDataOutput()
var videoDataOutputQueue: DispatchQueue!
var photoOutput: AVCapturePhotoOutput?
//var cameraPreviewLayer: AVCaptureVideoPreviewLayer?
var cameraPreviewLayer:CALayer!
//UIOutlets
#IBOutlet weak var cameraView: UIView!
#IBOutlet weak var captureImageView: UIImageView!
override func viewDidLoad() {
super.viewDidLoad()
self.cameraSetupSession()
self.setupDevice()
self.setupInputOutput()
self.setupPreviewLayer(on: cameraView)
self.startRunningCaptureSession()
// Do any additional setup after loading the view.
}
func cameraSetupSession(){
captureSession.sessionPreset = AVCaptureSession.Preset.photo
}
func setupDevice() {
print("2")
let deviceDiscoverySession = AVCaptureDevice.DiscoverySession(deviceTypes: [AVCaptureDevice.DeviceType.builtInUltraWideCamera], mediaType: .video , position: .unspecified)
let devices = deviceDiscoverySession.devices
for device in devices{
if device.position == .back{
backCamera = device
}else if device.position == .front{
frontCamera = device
}
}
currentCamera = backCamera
}
func setupInputOutput() {
print("3")
do{
let captureDeviceInput = try AVCaptureDeviceInput(device: currentCamera!)
print(captureDeviceInput)
captureSession.addInput(captureDeviceInput)
/*
let settings: [String : Any] = [
kCVPixelBufferPixelFormatTypeKey as String: NSNumber(value: kCVPixelFormatType_32BGRA),
]
videoOutput.videoSettings = settings
//videoOutput.setSampleBufferDelegate(self, queue: sessionQueue)
if captureSession.canAddOutput(videoOutput) {
captureSession.addOutput(videoOutput)
}
*/
let videoOutput = AVCaptureMovieFileOutput()
/*
videoOutput = AVCaptureVideoDataOutput()
videoDataOutputQueue = DispatchQueue(label: "VideoDataOutputQueue")
videoOutput.setSampleBufferDelegate(self, queue:self.videoDataOutputQueue)
*/
captureSession.addOutput(videoOutput)
//photoOutput?.setPreparedPhotoSettingsArray([AVCapturePhotoSettings(format:[AVVideoCodecKey:AVVideoCodecType.jpeg])], completionHandler: nil)
//captureSession.addOutput(photoOutput!)
}catch{
return
}
}
func setupPreviewLayer(on view: UIView) {
print("4")
/*
cameraPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
cameraPreviewLayer?.videoGravity = AVLayerVideoGravity.resizeAspectFill
cameraPreviewLayer?.masksToBounds = true
cameraPreviewLayer?.connection?.videoOrientation = .portrait
self.view.layer.insertSublayer(cameraPreviewLayer!, at: 0)
cameraPreviewLayer?.frame = view.frame
cameraPreviewLayer?.session = self.captureSession
*/
cameraPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
self.view.layer.addSublayer(self.cameraPreviewLayer)
self.cameraPreviewLayer.frame = self.view.layer.frame
}
func startRunningCaptureSession() {
print("5")
self.captureSession.startRunning()
print(self.captureSession.isRunning)
}
Commented parts which I changed. So that you can see the difference.