AVFoundation Camera Check and Flip Variable - ios

Question

I created a custom camera tool. Now, I am trying to handle checking existence of cameras however, I only have Simulator (no camera) and iphone (both cameras). I handled no camera but I couldn't understand how it works for one camera, so I also couldn't figure out how to help the user flip the camera
Currently I am using following external library using dojo custom camera
Position .Back and .Front works, and I handled no camera, but I couldn't figure out how to
handle checks for 1 camera
assign a variable for the control of Back & Front cameras depending on their existence (So I can create a uibutton in the VC and control flipping of camera back and front).
// I call addVideoInput() while initializing
func addVideoInput() {
if let device: AVCaptureDevice = self.deviceWithMediaTypeWithPosition(AVMediaTypeVideo, position: AVCaptureDevicePosition.Front) {
do {
let input = try AVCaptureDeviceInput(device: device)
if self.session.canAddInput(input) {
self.session.addInput(input)
}
} catch {
print(error)
}
}
}
func deviceWithMediaTypeWithPosition(mediaType: NSString, position: AVCaptureDevicePosition) -> AVCaptureDevice? {
let devices: NSArray = AVCaptureDevice.devicesWithMediaType(mediaType as String)
if devices.count != 0 {
if var captureDevice: AVCaptureDevice = devices.firstObject as? AVCaptureDevice {
for device in devices {
let d = device as! AVCaptureDevice
if d.position == position {
captureDevice = d
break;
}
}
print(captureDevice)
return captureDevice
}
}
print("doesnt have any camera")
return nil
}

Answer 1

You need to remove the object and create new object with use of few values and boolean uses.
Here I post the code for the when create the position of the camera AVCaptureDevicePosition.
In the top of the class add enum.
enum CameraType {
case Front
case Back
}
Initialise the variable.
var cameraCheck = CameraType.Back
Just change the following function.
func addVideoInput() {
if cameraCheck == CameraType.Front {
cameraCheck = CameraType.Back
let device: AVCaptureDevice = self.deviceWithMediaTypeWithPosition(AVMediaTypeVideo, position: AVCaptureDevicePosition.Front)
do {
let input = try AVCaptureDeviceInput(device: device)
if self.session.canAddInput(input) {
self.session.addInput(input)
}
} catch {
print(error)
}
}else{
cameraCheck = CameraType.Front
let device: AVCaptureDevice = self.deviceWithMediaTypeWithPosition(AVMediaTypeVideo, position: AVCaptureDevicePosition.Back)
do {
let input = try AVCaptureDeviceInput(device: device)
if self.session.canAddInput(input) {
self.session.addInput(input)
}
} catch {
print(error)
}
}
}
Create one button into your storyboard.
Now into your viewcontroller create one #IBAction function.
#IBAction func changeCamera(){
self.camera = nil
self.initializeCamera()
self.establishVideoPreviewArea()
if isBackCamera == true {
isBackCamera = false
self.camera?.cameraCheck = CameraType.Front
}else{
isBackCamera = true
self.camera?.cameraCheck = CameraType.Back
}
}
That's it your goal achieve.
Also you can download the source code from here.

Answer 2

You can use a boolean variable isUsingFrontCamera, for the first time when the camera view loads,
Set,
isUsingFrontCamera = false;
Then on clicking on the camera switch button,
-(IBAction)switchCameras:(id)sender {
AVCaptureDevicePosition desiredPosition;
if (isUsingFrontFacingCamera)
desiredPosition = AVCaptureDevicePositionBack;
else
desiredPosition = AVCaptureDevicePositionFront;
for (AVCaptureDevice *d in [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo]) {
if ([d position] == desiredPosition) {
[[captureVideoPreviewLayer session] beginConfiguration];
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:d error:nil];
for (AVCaptureInput *oldInput in [[captureVideoPreviewLayer session] inputs]) {
[[captureVideoPreviewLayer session] removeInput:oldInput];
}
[[captureVideoPreviewLayer session] addInput:input];
[[captureVideoPreviewLayer session] commitConfiguration];
break;
}
}
isUsingFrontFacingCamera = !isUsingFrontFacingCamera;
}
Where captureVideoPreviewLayer is the,
AVCaptureVideoPreviewLayer *captureVideoPreviewLayer
Also, you can get the count of your camera using
[[AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo] count]
Then show and hide button accordingly

Answer 3

Best to keep an enum IMO.
private enum CameraPosition {
case Front, Back
}
Then when you press the button have
var currentState: CameraPostition
switch to the other camera position.
Then on the didSet of currentState config the camera
var currentState: CameraPostition {
didSet {
configCamera(state: currentState)
}
}
EDIT: After some more information provided.
If you change
func addVideoInput() {
let device: AVCaptureDevice = self.deviceWithMediaTypeWithPosition(AVMediaTypeVideo, position: AVCaptureDevicePosition.Back)
do {
let input = try AVCaptureDeviceInput(device: device)
if self.session.canAddInput(input) {
self.session.addInput(input)
}
} catch {
print(error)
}
}
To
func addVideoInput(position: AVCaptureDevicePosition) {
let device: AVCaptureDevice = self.deviceWithMediaTypeWithPosition(AVMediaTypeVideo, position: position)
do {
let input = try AVCaptureDeviceInput(device: device)
if self.session.canAddInput(input) {
self.session.addInput(input)
}
} catch {
print(error)
}
}
Then when your "CurrentState" changes on the didSet of currentState you can just call the function.
func configCamera(state: CameraState) {
switch state{
case .Back:
addVideoInput(.Back)
case .Front
addVideoInput(.Front)
}
}