Capture current camera image using AVFoundation - ios

Question

I'm trying to capture the image and save it to a variable when I press "myButton". What should I do?
My code is as follows:
import UIKit
import AVFoundation
import MobileCoreServices
class ViewController: UIViewController {
let captureSession = AVCaptureSession()
var previewLayer : AVCaptureVideoPreviewLayer?
var captureDevice : AVCaptureDevice?
#IBOutlet var myTap: UITapGestureRecognizer!
#IBOutlet weak var myButton: UIButton!
#IBAction func shotPress(sender: UIButton) {
//Save image to variable somehow
})
var stillImageOutput = AVCaptureStillImageOutput()
stillImageOutput.outputSettings = [AVVideoCodecKey: AVVideoCodecJPEG]
if captureSession.canAddOutput(stillImageOutput) {
captureSession.addOutput(stillImageOutput)
}
}
override func viewDidLoad() {
super.viewDidLoad()
captureSession.sessionPreset = AVCaptureSessionPresetHigh
let devices = AVCaptureDevice.devices()
for device in devices {
if (device.hasMediaType(AVMediaTypeVideo)) {
if(device.position == AVCaptureDevicePosition.Back) {
captureDevice = device as? AVCaptureDevice
if captureDevice != nil {
beginSession()
}
}
}
}
}
func updateDeviceSettings(focusValue : Float, isoValue : Float) {
if let device = captureDevice {
if(device.lockForConfiguration(nil)) {
device.focusMode = AVCaptureFocusMode.ContinuousAutoFocus
device.unlockForConfiguration()
}
}
}
func beginSession() {
var err : NSError? = nil
captureSession.addInput(AVCaptureDeviceInput(device: captureDevice, error: &err))
if err != nil {
println("error: \(err?.localizedDescription)")
}
previewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
self.view.layer.addSublayer(previewLayer)
self.view.bringSubviewToFront(myButton)
previewLayer?.frame = self.view.layer.frame
captureSession.startRunning()
}
}

Answer 1

This is what I am using on one of the app that I am working on. Should be helpful for your problem as well.
func capturePicture(){
println("Capturing image")
stillImageOutput.outputSettings = [AVVideoCodecKey: AVVideoCodecJPEG]
captureSession.addOutput(stillImageOutput)
if let videoConnection = stillImageOutput.connectionWithMediaType(AVMediaTypeVideo){
stillImageOutput.captureStillImageAsynchronouslyFromConnection(videoConnection, completionHandler: {
(sampleBuffer, error) in
var imageData = AVCaptureStillImageOutput.jpegStillImageNSDataRepresentation(sampleBuffer)
var dataProvider = CGDataProviderCreateWithCFData(imageData)
var cgImageRef = CGImageCreateWithJPEGDataProvider(dataProvider, nil, true, CGColorRenderingIntent.RenderingIntentDefault)
var image = UIImage(CGImage: cgImageRef, scale: 1.0, orientation: UIImageOrientation.Right)
var imageView = UIImageView(image: image)
imageView.frame = CGRect(x:0, y:0, width:self.screenSize.width, height:self.screenSize.height)
//Show the captured image to
self.view.addSubview(imageView)
//Save the captured preview to image
UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
})
}
}

Answer 2

Updated for Swift 3:
var stillImageOutput = AVCaptureStillImageOutput.init()
stillImageOutput.outputSettings = [AVVideoCodecKey: AVVideoCodecJPEG]
self.cameraSession.addOutput(stillImageOutput)
if let videoConnection = stillImageOutput.connection(withMediaType:AVMediaTypeVideo){
stillImageOutput.captureStillImageAsynchronously(from:videoConnection, completionHandler: {
(sampleBuffer, error) in
var imageData = AVCaptureStillImageOutput.jpegStillImageNSDataRepresentation(sampleBuffer)
var dataProvider = CGDataProvider.init(data: imageData as! CFData)
var cgImageRef = CGImage.init(jpegDataProviderSource: dataProvider!, decode: nil, shouldInterpolate: true, intent: .defaultIntent)
var image = UIImage.init(cgImage: cgImageRef!, scale: 1.0, orientation: .right)
// do something with image
})
}