问题
Before iOS 10 came out I was using the following code to get the video and audio capture for my video recorder:
for device in AVCaptureDevice.devices()
{
if (device as AnyObject).hasMediaType( AVMediaTypeAudio )
{
self.audioCapture = device as? AVCaptureDevice
}
else if (device as AnyObject).hasMediaType( AVMediaTypeVideo )
{
if (device as AnyObject).position == AVCaptureDevicePosition.back
{
self.backCameraVideoCapture = device as? AVCaptureDevice
}
else
{
self.frontCameraVideoCapture = device as? AVCaptureDevice
}
}
}
When iOS 10 finally came out, I received the following warning when I was running my code. Note that my video recorder was still working smoothly for about 2 weeks.
'devices()' was deprecated in iOS 10.0: Use AVCaptureDeviceDiscoverySession instead.
As I was running my code this morning, my video recorder stopped working. xCode8 does not give me any errors but the previewLayer for the camera capture is completely white. When I then start recording I receive the following error:
Error Domain=AVFoundationErrorDomain Code=-11800 "The operation could not be completed" UserInfo={NSLocalizedDescription=The operation could not be completed, NSUnderlyingError=0x17554440 {Error Domain=NSOSStatusErrorDomain Code=-12780 "(null)"}, NSLocalizedFailureReason=An unknown error occurred (-12780)}
I believe that has something to do with the fact that I am using the deprecated approach AVCaptureDevice.devices(). Hence, I was wondering how to use AVCaptureDeviceDiscoverySession instead?
Thank you for your help in advance!
回答1:
You can get the front camera with the following:
AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .front)
The back camera:
AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .back)
And the microphone:
AVCaptureDevice.default(.builtInMicrophone, for: AVMediaType.audio, position: .unspecified)
回答2:
Swift 4, iOS 10+ and Xcode 10.1 replaces
if let cameraID = AVCaptureDevice.default(.builtInWideAngleCamera, for: .video, position: .front)?.localizedName {
//cameraID = "Front Camera"
}
with AVCaptureDevice.DiscoverySession implementation
if let cameraID = AVCaptureDevice.DiscoverySession.init(deviceTypes: [AVCaptureDevice.DeviceType.builtInWideAngleCamera], mediaType: .video, position: .front).devices.first?.localizedName{
//cameraID = "Front Camera"
}
Need to wrap it with #available(iOS 10,*) check.
回答3:
Here's my code (Swift 3) to get camera position :
// Find a camera with the specified AVCaptureDevicePosition, returning nil if one is not found
func cameraWithPosition(_ position: AVCaptureDevicePosition) -> AVCaptureDevice?
{
if let deviceDescoverySession = AVCaptureDeviceDiscoverySession.init(deviceTypes: [AVCaptureDeviceType.builtInWideAngleCamera],
mediaType: AVMediaTypeVideo,
position: AVCaptureDevicePosition.unspecified) {
for device in deviceDescoverySession.devices {
if device.position == position {
return device
}
}
}
return nil
}
If you want, you can also get the new devicesTypes from iPhone 7+ (dual camera) by changing the deviceTypes array.
Here's a good read : https://forums.developer.apple.com/thread/63347
回答4:
It works on Xcode 9.2 and Swift 4
AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .back)
https://developer.apple.com/documentation/avfoundation/avcapturedevice/2361508-default
回答5:
Swift 3
For selecting the back camera:(also you can change .back as needed)
For selecting another deviceType simple add it inside the [ ] (i.e:
[deviceTypeCamera, AVCaptureDeviceType.builtInMicrophone]
(or create a private let... like I did in the code with the back camera)
private let position = AVCaptureDevicePosition.back
private let deviceTypeBackCamera = AVCaptureDeviceType.builtInWideAngleCamera
private func selectCaptureDevice() -> AVCaptureDevice? {
return AVCaptureDeviceDiscoverySession(deviceTypes: [deviceTypeBackCamera], mediaType: AVMediaTypeVideo, position: position).devices.first
}
回答6:
example: iOS 11 Swift 4
override func viewDidLoad() {
super.viewDidLoad()
// Get the back-facing camera for capturing videos
// AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .back)
let deviceDiscoverySession = AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .back)
guard let captureDevice = deviceDiscoverySession else {
print("Failed to get the camera device")
return
}
do {
// Get an instance of the AVCaptureDeviceInput class using the previous device object.
let input = try AVCaptureDeviceInput(device: captureDevice)
// Set the input device on the capture session.
captureSession.addInput(input)
} catch {
// If any error occurs, simply print it out and don't continue any more.
print(error)
return
}
// Initialize the video preview layer and add it as a sublayer to the viewPreview view's layer.
videoPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
videoPreviewLayer?.videoGravity = AVLayerVideoGravity.resizeAspectFill
videoPreviewLayer?.frame = view.layer.bounds
view.layer.addSublayer(videoPreviewLayer!)
// Start video capture.
captureSession.startRunning()
回答7:
Try below code to get camera ID:
NSString *cameraID = nil;
NSArray *captureDeviceType = @[AVCaptureDeviceTypeBuiltInWideAngleCamera];
AVCaptureDeviceDiscoverySession *captureDevice =
[AVCaptureDeviceDiscoverySession
discoverySessionWithDeviceTypes:captureDeviceType
mediaType:AVMediaTypeVideo
position:AVCaptureDevicePositionUnspecified];
cameraID = [captureDevice.devices.lastObject localizedName];
回答8:
For my video capture app I'm using the following code to get the mic, front and rear camera and I've tested this code from iOS 7 to 10.0.2.
var frontCamera : AVCaptureDevice?
var rearCamera : AVCaptureDevice?
captureSession = AVCaptureSession()
let devices = AVCaptureDevice.devicesWithMediaType(AVMediaTypeVideo)
let audioDevices = AVCaptureDevice.devicesWithMediaType(AVMediaTypeAudio)
for mic in audioDevices {
audioDevice = mic as? AVCaptureDevice
audioCapturePossible = true
}
for device in devices {
if device.position == AVCaptureDevicePosition.Front {
frontCamera = device as? AVCaptureDevice
hasFrontCamera = true
}
else if device.position == AVCaptureDevicePosition.Back {
rearCamera = device as? AVCaptureDevice
hasRearCamera = true
}
}
回答9:
Swift 4 (xCode 10.1)
This is what worked for me in the latest version of Swift. I did not see this answer, and it took me a while to suss out so here is how to get the front facing camera.
if let device = AVCaptureDevice.defaultDevice(withDeviceType: .builtInWideAngleCamera , mediaType: AVMediaTypeVideo, position: .front) {
//Do the camera thing here..
}
回答10:
05/2019 :
//video
self.session = AVCaptureSession()
guard
let videoDeviceInput = try? AVCaptureDeviceInput(device: device!),
self.session!.canAddInput(videoDeviceInput)
else { return }
self.session!.addInput(videoDeviceInput)
//audio
guard
let audioDeviceInput = try? AVCaptureDeviceInput(device: mic!),
self.session!.canAddInput(audioDeviceInput)
else { return }
self.session!.addInput(audioDeviceInput)
来源：https://stackoverflow.com/questions/39894630/how-to-get-front-camera-back-camera-and-audio-with-avcapturedevicediscoverysess