Flip front camera image so they match the preview that was shown

Author: AlexLittlejohn

ALCameraViewController/Utilities/CameraShot.swift

@@ -11,7 +11,7 @@ import AVFoundation
 
 public typealias CameraShotCompletion = (UIImage?) -> Void
 
-public func takePhoto(_ stillImageOutput: AVCaptureStillImageOutput, videoOrientation: AVCaptureVideoOrientation, cropSize: CGSize, completion: @escaping CameraShotCompletion) {
+public func takePhoto(_ stillImageOutput: AVCaptureStillImageOutput, videoOrientation: AVCaptureVideoOrientation, cameraPosition: AVCaptureDevicePosition, cropSize: CGSize, completion: @escaping CameraShotCompletion) {
 
     guard let videoConnection: AVCaptureConnection = stillImageOutput.connection(withMediaType: AVMediaTypeVideo) else {
         completion(nil)
@@ -24,10 +24,32 @@ public func takePhoto(_ stillImageOutput: AVCaptureStillImageOutput, videoOrient
 
         guard let buffer = buffer,
             let imageData = AVCaptureStillImageOutput.jpegStillImageNSDataRepresentation(buffer),
-            let image = UIImage(data: imageData) else {
+            var image = UIImage(data: imageData) else {
             completion(nil)
             return
         }
+
+        // flip the image to match the orientation of the preview
+        if cameraPosition == .front, let cgImage = image.cgImage {
+            switch image.imageOrientation {
+            case .leftMirrored:
+                image = UIImage(cgImage: cgImage, scale: image.scale, orientation: .right)
+            case .left:
+                image = UIImage(cgImage: cgImage, scale: image.scale, orientation: .rightMirrored)
+            case .rightMirrored:
+                image = UIImage(cgImage: cgImage, scale: image.scale, orientation: .left)
+            case .right:
+                image = UIImage(cgImage: cgImage, scale: image.scale, orientation: .leftMirrored)
+            case .up:
+                image = UIImage(cgImage: cgImage, scale: image.scale, orientation: .upMirrored)
+            case .upMirrored:
+                image = UIImage(cgImage: cgImage, scale: image.scale, orientation: .up)
+            case .down:
+                image = UIImage(cgImage: cgImage, scale: image.scale, orientation: .downMirrored)
+            case .downMirrored:
+                image = UIImage(cgImage: cgImage, scale: image.scale, orientation: .down)
+            }
+        }
 
         completion(image)
     })

ALCameraViewController/Views/CameraView.swift

@@ -162,7 +162,7 @@ public class CameraView: UIView {
         let size = frame.size
 
         cameraQueue.sync {
-            takePhoto(output, videoOrientation: orientation, cropSize: size) { image in
+            takePhoto(output, videoOrientation: orientation, cameraPosition: device.position, cropSize: size) { image in
                 DispatchQueue.main.async() { [weak self] in
                     self?.isUserInteractionEnabled = true
                     completion(image)