您应该在捕获照片之前设置输出方向。

// set the image orientation in output
  if let photoOutputConnection = self.photoOutput.connection(with: .video) {
        photoOutputConnection.videoOrientation = videoPreviewLayerOrientation!
    }

self.photoOutput.capturePhoto(with: photoSettings, delegate: photoCaptureProcessor) // capture image

这真的是一个很烦人的问题，我真的不相信AVFoundation没有任何更简单的东西给我们。但在我的应用程序中，我是通过保持当前设备的方向来实现这一点的。当照片输出返回图像时，使用方向旋转图像，以确保所有图片都是向上的。

class MyViewController: UIViewController {

    var currentOrientation: UIDeviceOrientation = .portrait

    override func viewDidLoad() {
        NotificationCenter.default.addObserver(self, selector: #selector(orientationChanged), name: UIDevice.orientationDidChangeNotification, object: nil)
    }

    @objc func orientationChanged() {
        currentOrientation = UIDevice.current.orientation
    }

    func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {
        guard let img = photo.cgImageRepresentation()?.takeUnretainedValue() else { return }
        let temp = CIImage(cgImage: img)
        var ciImage = temp;
        switch currentOrientation {
            case .portrait:
                ciImage = temp.oriented(forExifOrientation: 6)
            case .landscapeRight:
                ciImage = temp.oriented(forExifOrientation: 3)
            case .landscapeLeft:
                ciImage = temp.oriented(forExifOrientation: 1)
            default:
                break
        }

        guard let cgImage = CIContext(options: nil).createCGImage(ciImage, from: ciImage.extent) else { return }
        let fixedImage = UIImage(cgImage: cgImage)
    }

}

最后，使用fixedImage来满足您的需要。请注意，我订阅了方向更改的通知中心。

enum CGImageOrientation {
case up
case down
case left
case right
case upMirrored
case downMirrored
case leftMirrored
case rightMirrored
}

  extension CGImage {
   func orientImage(_ imageOrientation: CGImageOrientation) -> 
   CGImage? {
    return orientImageWithTransform(imageOrientation).0
 }

func orientImageWithTransform(_ imageOrientation: CGImageOrientation) -> (CGImage?, CGAffineTransform) {

    var transform = CGAffineTransform.identity
    if imageOrientation == .up { return (self.copy(), transform)}

    let size = CGSize(width: width, height: height)
    let newSize = [.left,.leftMirrored, .right, .rightMirrored].contains(imageOrientation)
        ? CGSize(width: size.height, height: size.width) : size

    // Guard that we have color space and core graphics context.
    guard let colorSpace = self.colorSpace,
        // New graphic context uses transformed width and height.
        let ctx = CGContext(data: nil, width: Int(newSize.width), height: Int(newSize.height),
                            bitsPerComponent: self.bitsPerComponent, bytesPerRow: 0,
                            space: colorSpace, bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue)
        else { return (nil, transform)}

    // OK, now the actual work of constructing transform and creating new image.
    switch imageOrientation {
    case .down, .downMirrored:
        transform = transform.translatedBy(x: size.width, y: size.height)
        transform = transform.rotated(by: CGFloat.pi)
        break
    case .left,.leftMirrored:
        transform = transform.translatedBy(x: size.height, y: 0)
        transform = transform.rotated(by: CGFloat.pi/2)
        break
    case .right, .rightMirrored:
        transform = transform.translatedBy(x: 0, y: size.width)
        transform = transform.rotated(by: -CGFloat.pi/2)
        break
    case .up, .upMirrored:
        break
    }

    if [.upMirrored, .downMirrored,.leftMirrored, .rightMirrored].contains(imageOrientation) {
        transform = transform.translatedBy(x: size.width, y: 0)
        transform = transform.scaledBy(x: -1, y: 1)
    }

    ctx.concatenate(transform)
    // Interestingly, drawing with the original width and height?!
    // So width and height here are pre-transform.

    ctx.draw(self, in: CGRect(x: 0, y: 0, width: size.width, height: size.height))

    return (ctx.makeImage(), transform)
}

}
用途：

var tempImage = imgae
        guard let cgImage = imgae?.cgImage else {return}

        if let orientedImage = cgImage.orientImage(.upMirrored) {
            tempImage = UIImage(cgImage: orientedImage)
        }
        let image = UIImageView(image: tempImage)

这里的问题是，在将UIImage转换为CGImage时，您将丢弃图像元数据（包括方向）。

if let data = photo.fileDataRepresentation(), let image = UIImage(data: data) {
    let renderedImage = UIGraphicsImageRenderer(size: size, format: imageRendererFormat).image { _ in image.draw(at: .zero) }
    // use renderedImage image
}

尝试以下功能来固定方向：

extension UIImage {
    func makeFixOrientation() -> UIImage {
        if self.imageOrientation == UIImage.Orientation.up {
            return self
        }

        UIGraphicsBeginImageContextWithOptions(self.size, false, self.scale)
        self.draw(in: CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height))
        let normalizedImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()

        return normalizedImage;
    }
}

从iOS 4.0开始，当相机拍摄照片时，它在保存之前不旋转它，它

• 如果您将UIImage保存为JPEG格式，则只需要在JPEG的EXIF数据中设置一个旋转标志。
• 它将设置循环标志。PNG不支持循环标志。
• 所以如果你把一个UIImage保存为PNG，它将被错误地旋转，并且没有一个标记来修复它。所以如果你想要PNG图像，你必须自己旋转它们。

func rotateImage(image: UIImage) -> UIImage? {
            if (image.imageOrientation == UIImage.Orientation.up ) {
                return image
            }
            UIGraphicsBeginImageContext(image.size)
            image.draw(in: CGRect(origin: CGPoint.zero, size: image.size))
            let copy = UIGraphicsGetImageFromCurrentImageContext()
            UIGraphicsEndImageContext()
            return copy
        }