ios - 从相机拍摄的 UIImage 裁剪 CGRect
问题描述
我有一个视图控制器,它在中心拍摄一张带有圆形视图的照片。拍照后,我需要裁剪用于创建圆形视图的 CGRect。我需要裁剪矩形,而不是圆形。我尝试了https://stackoverflow.com/a/57258806/12411655和许多其他解决方案,但它没有裁剪我需要的 CGRect 。如何将视图坐标中的 CGRect 转换为 UIImage 的坐标?
class CircularCameraViewController: UIViewController {
var captureSession: AVCaptureSession!
var capturePhotoOutput: AVCapturePhotoOutput!
var cropRect: CGRect!
public lazy var shutterButton: ShutterButton = {
let button = ShutterButton()
button.translatesAutoresizingMaskIntoConstraints = false
button.addTarget(self, action: #selector(capturePhoto), for: .touchUpInside)
return button
}()
private lazy var cancelButton: UIButton = {
let button = UIButton()
button.setTitle("Cancel", for: .normal)
button.translatesAutoresizingMaskIntoConstraints = false
button.addTarget(self, action: #selector(dismissCamera), for: .touchUpInside)
return button
}()
private lazy var flashButton: UIButton = {
let image = UIImage(named: "flash", in: Bundle(for: ScannerViewController.self), compatibleWith: nil)?.withRenderingMode(.alwaysTemplate)
let button = UIButton()
button.setImage(image, for: .normal)
button.translatesAutoresizingMaskIntoConstraints = false
button.addTarget(self, action: #selector(toggleFlash), for: .touchUpInside)
button.tintColor = .white
return button
}()
override func viewDidLoad() {
super.viewDidLoad()
setupCamera()
setupPhotoOutput()
setupViews()
setupConstraints()
captureSession.startRunning()
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
}
override func viewWillDisappear(_ animated: Bool) {
captureSession.stopRunning()
}
private func setupCamera() {
let captureDevice = AVCaptureDevice.default(for: AVMediaType.video)
var input: AVCaptureDeviceInput
do {
input = try AVCaptureDeviceInput(device: captureDevice!)
} catch {
fatalError("Error configuring capture device: \(error)");
}
captureSession = AVCaptureSession()
captureSession.addInput(input)
// Setup the preview view.
let videoPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
videoPreviewLayer.videoGravity = AVLayerVideoGravity.resizeAspectFill
videoPreviewLayer.frame = view.layer.bounds
view.layer.addSublayer(videoPreviewLayer)
let camPreviewBounds = view.bounds
cropRect = CGRect(
x: camPreviewBounds.minX + (camPreviewBounds.width - 150) * 0.5,
y: camPreviewBounds.minY + (camPreviewBounds.height - 150) * 0.5,
width: 150,
height: 150
)
let path = UIBezierPath(roundedRect: camPreviewBounds, cornerRadius: 0)
path.append(UIBezierPath(ovalIn: cropRect))
let layer = CAShapeLayer()
layer.path = path.cgPath
layer.fillRule = CAShapeLayerFillRule.evenOdd;
layer.fillColor = UIColor.black.cgColor
layer.opacity = 0.5;
view.layer.addSublayer(layer)
}
private func setupViews() {
view.addSubview(shutterButton)
view.addSubview(flashButton)
view.addSubview(cancelButton)
}
private func setupConstraints() {
var cancelButtonConstraints = [NSLayoutConstraint]()
var shutterButtonConstraints = [NSLayoutConstraint]()
var flashConstraints = [NSLayoutConstraint]()
shutterButtonConstraints = [
shutterButton.centerXAnchor.constraint(equalTo: view.centerXAnchor),
shutterButton.widthAnchor.constraint(equalToConstant: 65.0),
shutterButton.heightAnchor.constraint(equalToConstant: 65.0)
]
flashConstraints = [
flashButton.leftAnchor.constraint(equalTo: view.leftAnchor, constant: 24.0),
flashButton.topAnchor.constraint(equalTo: view.topAnchor, constant: 30)
]
if #available(iOS 11.0, *) {
cancelButtonConstraints = [
cancelButton.leftAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leftAnchor, constant: 24.0),
view.safeAreaLayoutGuide.bottomAnchor.constraint(equalTo: cancelButton.bottomAnchor, constant: (65.0 / 2) - 10.0)
]
let shutterButtonBottomConstraint = view.safeAreaLayoutGuide.bottomAnchor.constraint(equalTo: shutterButton.bottomAnchor, constant: 8.0)
shutterButtonConstraints.append(shutterButtonBottomConstraint)
} else {
cancelButtonConstraints = [
cancelButton.leftAnchor.constraint(equalTo: view.leftAnchor, constant: 24.0),
view.bottomAnchor.constraint(equalTo: cancelButton.bottomAnchor, constant: (65.0 / 2) - 10.0)
]
let shutterButtonBottomConstraint = view.bottomAnchor.constraint(equalTo: shutterButton.bottomAnchor, constant: 8.0)
shutterButtonConstraints.append(shutterButtonBottomConstraint)
}
NSLayoutConstraint.activate(cancelButtonConstraints + shutterButtonConstraints + flashConstraints)
}
private func setupPhotoOutput() {
capturePhotoOutput = AVCapturePhotoOutput()
capturePhotoOutput.isHighResolutionCaptureEnabled = true
captureSession.addOutput(capturePhotoOutput!)
}
@objc func dismissCamera() {
self.dismiss(animated: true, completion: nil)
}
@objc private func toggleFlash() {
if let avDevice = AVCaptureDevice.default(for: AVMediaType.video) {
if (avDevice.hasTorch) {
do {
try avDevice.lockForConfiguration()
} catch {
print("aaaa")
}
if avDevice.isTorchActive {
avDevice.torchMode = AVCaptureDevice.TorchMode.off
} else {
avDevice.torchMode = AVCaptureDevice.TorchMode.on
}
}
// unlock your device
avDevice.unlockForConfiguration()
}
}
}
extension CircularCameraViewController : AVCapturePhotoCaptureDelegate {
@objc private func capturePhoto() {
let photoSettings = AVCapturePhotoSettings()
photoSettings.isAutoStillImageStabilizationEnabled = true
photoSettings.isHighResolutionPhotoEnabled = true
photoSettings.flashMode = .auto
// Set ourselves as the delegate for `capturePhoto`.
capturePhotoOutput?.capturePhoto(with: photoSettings, delegate: self)
}
@available(iOS 11.0, *)
func photoOutput(_ output: AVCapturePhotoOutput,
didFinishProcessingPhoto photo: AVCapturePhoto,
error: Error?) {
guard error == nil else {
fatalError("Failed to capture photo: \(String(describing: error))")
}
guard let imageData = photo.fileDataRepresentation() else {
fatalError("Failed to convert pixel buffer")
}
guard let image = UIImage(data: imageData) else {
fatalError("Failed to convert image data to UIImage")
}
guard let croppedImg = image.cropToRect(rect: cropRect) else {
fatalError("Failed to crop image")
}
UIImageWriteToSavedPhotosAlbum(croppedImg, nil, nil, nil);
}
func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photoSampleBuffer: CMSampleBuffer?, previewPhoto previewPhotoSampleBuffer: CMSampleBuffer?, resolvedSettings: AVCaptureResolvedPhotoSettings, bracketSettings: AVCaptureBracketedStillImageSettings?, error: Error?) {
guard error == nil, let photoSample = photoSampleBuffer else {
fatalError("Failed to capture photo: \(String(describing: error))")
}
guard let imgData = AVCapturePhotoOutput.jpegPhotoDataRepresentation(forJPEGSampleBuffer: photoSample, previewPhotoSampleBuffer: previewPhotoSampleBuffer) else {
fatalError("Failed to get image data: \(String(describing: error))")
}
guard let image = UIImage(data: imgData) else {
fatalError("Failed to convert image data to UIImage: \(String(describing: error))")
}
}
}
UIImage 扩展:
func cropToRect(rect: CGRect!) -> UIImage? {
let scaledRect = CGRect(x: rect.origin.x * self.scale, y: rect.origin.y * self.scale, width: rect.size.width * self.scale, height: rect.size.height * self.scale);
guard let imageRef: CGImage = self.cgImage?.cropping(to:scaledRect)
else {
return nil
}
let croppedImage: UIImage = UIImage(cgImage: imageRef, scale: self.scale, orientation: self.imageOrientation)
return croppedImage
}
解决方案
裁剪图像时,您需要从相对于图像大小的大小缩放“裁剪矩形”。
此外,从相机拍摄时,您需要考虑.imageOrientation
到这一点。
尝试将您的UIImage
扩展名更改为:
extension UIImage {
func cropToRect(rect: CGRect, viewSize: CGSize) -> UIImage? {
var cr = rect
switch self.imageOrientation {
case .right, .rightMirrored, .left, .leftMirrored:
// rotate the crop rect if needed
cr.origin.x = rect.origin.y
cr.origin.y = rect.origin.x
cr.size.width = rect.size.height
cr.size.height = rect.size.width
default:
break
}
let imageViewScale = max(self.size.width / viewSize.width,
self.size.height / viewSize.height)
// scale the crop rect
let cropZone = CGRect(x:cr.origin.x * imageViewScale,
y:cr.origin.y * imageViewScale,
width:cr.size.width * imageViewScale,
height:cr.size.height * imageViewScale)
// Perform cropping in Core Graphics
guard let cutImageRef: CGImage = self.cgImage?.cropping(to:cropZone)
else {
return nil
}
// Return image to UIImage
let croppedImage: UIImage = UIImage(cgImage: cutImageRef, scale: self.scale, orientation: self.imageOrientation)
return croppedImage
}
}
并将您的电话更改photoOutput()
为:
guard let croppedImg = image.cropToRect(rect: cropRect, viewSize: view.frame.size) else {
fatalError("Failed to crop image")
}
由于您的代码使用的是完整视图,因此应该可以正常工作。如果您将其更改为使用不同大小的视图,videoPreviewLayer
则使用该大小而不是view.frame.size
.
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