【发布时间】：2018-03-09 17:47:36
【问题描述】：
目前我有两个不同的视图控制器和一个在它们之间切换的按钮。 我希望能够在每个设备上拍摄设备输入的照片。
我目前能够拍摄后置摄像头的照片以进行处理并且效果很好，但是当我尝试在另一个控制器中为第二个视图编写相同的代码时，照片输出返回 nil，但是当我记录每个设备，它仍然显示前后摄像头。
我对 swift 还很陌生，不知道为什么会这样。
ViewController 类、viewDidLoad 和变量：
class AddUserController: UIViewController , AVCaptureVideoDataOutputSampleBufferDelegate , UITextFieldDelegate{
//variable for captureing video feed
var captureSessionFront = AVCaptureSession()
//variable for rendering camera to the view
var videoPreviewLayer: AVCaptureVideoPreviewLayer?
var frontCamera: AVCaptureDevice?
var backCamera: AVCaptureDevice?
var currentCamera2: AVCaptureDevice?
var PhotoOutputFront: AVCapturePhotoOutput?
var cameraPreviewLayer2: AVCaptureVideoPreviewLayer?
var tempImage: UIImage?
var tempstring: String?
private var maskLayer = [CAShapeLayer]()
@IBOutlet weak var textField: UITextField!
//button action to save the user to the collection
@IBAction func saveFaceBtn(_ sender: Any) {
let settings = AVCapturePhotoSettings()
PhotoOutputFront?.capturePhoto(with: settings, delegate: self)
//print(PhotoOutputFront!)
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
//hide keyboard
self.textField.delegate = self
//video capture functions
setupCaptureSession()
setupDevice()
setupInputOutput()
setupPreview()
startRunningCaptureSession()
功能：
func setupCaptureSession() {
captureSessionFront.sessionPreset = AVCaptureSession.Preset.photo
}
func setupDevice() {
//discover devices
let deviceDiscoverySession = AVCaptureDevice.DiscoverySession(
deviceTypes: [AVCaptureDevice.DeviceType.builtInWideAngleCamera],
mediaType: AVMediaType.video,
position: AVCaptureDevice.Position.unspecified)
//find devices and check if frint or back cameras discovered
let devices = deviceDiscoverySession.devices
for device in devices{
print(device)
if device.position == AVCaptureDevice.Position.front{
frontCamera = device
} else if device.position == AVCaptureDevice.Position.back{
backCamera = device
}
}
currentCamera2 = frontCamera
}
func setupInputOutput() {
do
{
let captureDeviceInput2 = try AVCaptureDeviceInput(device: currentCamera2!)
captureSessionFront.addInput(captureDeviceInput2)
PhotoOutputFront?.setPreparedPhotoSettingsArray([AVCapturePhotoSettings(format: [AVVideoCodecKey: AVVideoCodecType.jpeg])], completionHandler: nil)
print(PhotoOutputFront)
}
catch
{
print(error)
}
}
func setupPreview() {
cameraPreviewLayer2 = AVCaptureVideoPreviewLayer(session: captureSessionFront)
cameraPreviewLayer2?.videoGravity = AVLayerVideoGravity.resizeAspectFill
cameraPreviewLayer2?.connection?.videoOrientation = AVCaptureVideoOrientation.portrait
cameraPreviewLayer2?.frame = self.view.frame
self.view.layer.insertSublayer(cameraPreviewLayer2!, at: 0)
}
func startRunningCaptureSession() {
captureSessionFront.startRunning()
}
保存拍摄照片的扩展程序：
extension AddUserController: AVCapturePhotoCaptureDelegate {
func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {
print("before if let")
if let imageData = photo.fileDataRepresentation(){
tempImage = UIImage(data: imageData)
print(tempImage!)
//check to see if name is empty
let tempstring = self.textField.text
if(tempstring != nil || tempstring != ""){
print(tempstring!)
//addPhotoToCollection()
}
}
}
}
它必须是设置输入输出的东西，但我不确定我哪里出错了，因为这段代码适用于我的主视图控制器中的后置摄像头。我认为这与此功能有关，因为在我的其他控制器“PhotoOutput”中不返回零。在这里，“PhotoOutputFront”返回 nil。
view func setupInputOutput() {
do
{
let captureDeviceInput2 = try AVCaptureDeviceInput(device: currentCamera2!)
captureSessionFront.addInput(captureDeviceInput2)
PhotoOutputFront?.setPreparedPhotoSettingsArray([AVCapturePhotoSettings(format: [AVVideoCodecKey: AVVideoCodecType.jpeg])], completionHandler: nil)
print(PhotoOutputFront)
}
catch
{
print(error)
}
}
任何帮助将不胜感激。提前致谢！
【问题讨论】：
标签： ios swift avcapturesession avcapturedevice