Saya telah membuat kamera khusus dan menerapkan kode di bawah ini untuk memotong gambar yang diambil, saya telah menunjukkan panduan di lapisan pratinjau jadi saya ingin memotong gambar yang muncul di area itu.
func imageByCropToRect(rect:CGRect, scale:Bool) -> UIImage {
var rect = rect
var scaleFactor: CGFloat = 1.0
if scale {
scaleFactor = self.scale
rect.origin.x *= scaleFactor
rect.origin.y *= scaleFactor
rect.size.width *= scaleFactor
rect.size.height *= scaleFactor
}
var image: UIImage? = nil;
if rect.size.width > 0 && rect.size.height > 0 {
let imageRef = self.cgImage!.cropping(to: rect)
image = UIImage(cgImage: imageRef!, scale: scaleFactor, orientation: self.imageOrientation)
}
return image!
}
Kode ini hanya berfungsi dengan baik ketika & memberikan gambar yang dipotong persis ketika baris kode di bawah ini dikomentari, meskipun saya ingin streaming gambar dalam layar penuh jadi saya harus menggunakan baris kode di bawah ini. Gambarnya diperbesar.
(self.previewLayer as! AVCaptureVideoPreviewLayer).videoGravity = AVLayerVideoGravity.resizeAspectFill
Bagaimana cara mengatasi masalah ini? Apakah kode pemangkasannya salah?
Berikut adalah kode Kelas selengkapnya
import UIKit
import AVFoundation
class CameraViewController: UIViewController {
@IBOutlet weak var guideImageView: UIImageView!
@IBOutlet weak var guidesView: UIView!
@IBOutlet weak var cameraPreviewView: UIView!
@IBOutlet weak var cameraButtonView: UIView!
@IBOutlet weak var captureButton: UIButton!
var captureSession = AVCaptureSession()
var previewLayer: CALayer!
var captureDevice: AVCaptureDevice!
/// This will be true when the user clicks on the click photo button.
var takePhoto = false
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
captureSession = AVCaptureSession()
previewLayer = CALayer()
takePhoto = false
requestAuthorization()
}
private func userinteractionToButton(_ interaction: Bool) {
captureButton.isEnabled = interaction
}
/// This function will request authorization, If authorized then start the camera.
private func requestAuthorization() {
switch AVCaptureDevice.authorizationStatus(for: AVMediaType.video) {
case .authorized:
prepareCamera()
case .denied, .restricted, .notDetermined:
AVCaptureDevice.requestAccess(for: AVMediaType.video, completionHandler: { (granted) in
if !Thread.isMainThread {
DispatchQueue.main.async {
if granted {
self.prepareCamera()
} else {
let alert = UIAlertController(title: "unable_to_access_the_Camera", message: "to_enable_access_go_to_setting_privacy_camera_and_turn_on_camera_access_for_this_app", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "ok", style: .default, handler: {_ in
self.navigationController?.popToRootViewController(animated: true)
}))
self.present(alert, animated: true, completion: nil)
}
}
} else {
if granted {
self.prepareCamera()
} else {
let alert = UIAlertController(title: "unable_to_access_the_Camera", message: "to_enable_access_go_to_setting_privacy_camera_and_turn_on_camera_access_for_this_app", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "ok", style: .default, handler: {_ in
self.navigationController?.popToRootViewController(animated: true)
}))
self.present(alert, animated: true, completion: nil)
}
}
})
}
}
/// Will see if the primary camera is avilable, If found will call method which will asign the available device to the AVCaptureDevice.
private func prepareCamera() {
// Resets the session.
self.captureSession.sessionPreset = AVCaptureSession.Preset.photo
if #available(iOS 10.0, *) {
let availableDevices = AVCaptureDevice.DiscoverySession(deviceTypes: [AVCaptureDevice.DeviceType.builtInWideAngleCamera], mediaType: AVMediaType.video, position: .back).devices
self.assignCamera(availableDevices)
} else {
// Fallback on earlier versions
// development, need to test this on iOS 8
if let availableDevices = AVCaptureDevice.default(for: AVMediaType.video) {
self.assignCamera([availableDevices])
} else {
self.showAlert()
}
}
}
/// Assigns AVCaptureDevice to the respected the variable, will begin the session.
///
/// - Parameter availableDevices: [AVCaptureDevice]
private func assignCamera(_ availableDevices: [AVCaptureDevice]) {
if availableDevices.first != nil {
captureDevice = availableDevices.first
beginSession()
} else {
self.showAlert()
}
}
/// Configures the camera settings and begins the session, this function will be responsible for showing the image on the UI.
private func beginSession() {
do {
let captureDeviceInput = try AVCaptureDeviceInput(device: captureDevice)
captureSession.addInput(captureDeviceInput)
} catch {
print(error.localizedDescription)
}
let previewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
self.previewLayer = previewLayer
self.cameraPreviewView.layer.addSublayer(self.previewLayer)
self.previewLayer.frame = self.view.layer.frame
self.previewLayer.frame.origin.y = +self.cameraPreviewView.frame.origin.y
(self.previewLayer as! AVCaptureVideoPreviewLayer).videoGravity = AVLayerVideoGravity.resizeAspectFill
self.previewLayer.masksToBounds = true
self.cameraPreviewView.clipsToBounds = true
captureSession.startRunning()
self.view.bringSubview(toFront: self.cameraPreviewView)
self.view.bringSubview(toFront: self.cameraButtonView)
self.view.bringSubview(toFront: self.guidesView)
let dataOutput = AVCaptureVideoDataOutput()
dataOutput.videoSettings = [((kCVPixelBufferPixelFormatTypeKey as NSString) as String):NSNumber(value:kCVPixelFormatType_32BGRA)]
dataOutput.alwaysDiscardsLateVideoFrames = true
if captureSession.canAddOutput(dataOutput) {
captureSession.addOutput(dataOutput)
}
captureSession.commitConfiguration()
let queue = DispatchQueue(label: "com.letsappit.camera")
dataOutput.setSampleBufferDelegate(self, queue: queue)
self.userinteractionToButton(true)
}
/// Get the UIImage from the given CMSampleBuffer.
///
/// - Parameter buffer: CMSampleBuffer
/// - Returns: UIImage?
func getImageFromSampleBuffer(buffer:CMSampleBuffer, orientation: UIImageOrientation) -> UIImage? {
if let pixelBuffer = CMSampleBufferGetImageBuffer(buffer) {
let ciImage = CIImage(cvPixelBuffer: pixelBuffer)
let context = CIContext()
let imageRect = CGRect(x: 0, y: 0, width: CVPixelBufferGetWidth(pixelBuffer), height: CVPixelBufferGetHeight(pixelBuffer))
if let image = context.createCGImage(ciImage, from: imageRect) {
return UIImage(cgImage: image, scale: UIScreen.main.scale, orientation: orientation)
}
}
return nil
}
/// This function will destroy the capture session.
func stopCaptureSession() {
self.captureSession.stopRunning()
if let inputs = captureSession.inputs as? [AVCaptureDeviceInput] {
for input in inputs {
self.captureSession.removeInput(input)
}
}
}
func showAlert() {
let alert = UIAlertController(title: "Unable to access the camera", message: "It appears that either your device doesn't have camera or its broken", preferredStyle: .alert)
alert.addAction(UIAlertAction(title: "cancel", style: .cancel, handler: {_ in
self.navigationController?.dismiss(animated: true, completion: nil)
}))
self.present(alert, animated: true, completion: nil)
}
@IBAction func didTapClick(_ sender: Any) {
userinteractionToButton(false)
takePhoto = true
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "showImage" {
let vc = segue.destination as! ShowImageViewController
vc.image = sender as! UIImage
}
}
}
extension CameraViewController: AVCaptureVideoDataOutputSampleBufferDelegate {
func captureOutput(_ captureOutput: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) {
if connection.isVideoOrientationSupported {
connection.videoOrientation = .portrait
}
if takePhoto {
takePhoto = false
// Rotation should be unlocked to work.
var orientation = UIImageOrientation.up
switch UIDevice.current.orientation {
case .landscapeLeft:
orientation = .left
case .landscapeRight:
orientation = .right
case .portraitUpsideDown:
orientation = .down
default:
orientation = .up
}
if let image = self.getImageFromSampleBuffer(buffer: sampleBuffer, orientation: orientation) {
DispatchQueue.main.async {
let newImage = image.imageByCropToRect(rect: self.guideImageView.frame, scale: true)
self.stopCaptureSession()
self.previewLayer.removeFromSuperlayer()
self.performSegue(withIdentifier: "showImage", sender: newImage)
}
}
}
}
}
Berikut gambar hierarki tampilan 
