相机仅在人像模式下快速拍照

Question

如何将相机设置为横向模式？每次我拍照时，图像都会保存为肖像图像。当设备处于横向模式时，照片看起来不错，但如果我在相机胶卷中看到它，它仍然是纵向模式。 这是我的拍照功能：

// take a photo
@IBAction func takePhoto(sender: AnyObject) {
self.fullScreenView.hidden = false
self.recordButton.enabled = false
self.takephoto.enabled = false
self.recordButton.hidden = true
self.takephoto.hidden = true

session.startRunning()

// customize the quality level or bitrate of the output photo
session.sessionPreset = AVCaptureSessionPresetPhoto

// add the AVCaptureVideoPreviewLayer to the view and set the view in fullscreen
fullScreenView.frame = view.bounds
videoPreviewLayer.frame = fullScreenView.bounds
fullScreenView.layer.addSublayer(videoPreviewLayer)

// add action to fullScreenView
gestureFullScreenView = UITapGestureRecognizer(target: self, action: #selector(ViewController.takePhoto(_:)))
self.fullScreenView.addGestureRecognizer(gestureFullScreenView)

// add action to myView
gestureView = UITapGestureRecognizer(target: self, action: #selector(ViewController.setFrontpage(_:)))
self.view.addGestureRecognizer(gestureView)

if (preview == true) {
    if let videoConnection = stillImageOutput!.connectionWithMediaType(AVMediaTypeVideo) {
        // code for photo capture goes here...

        stillImageOutput?.captureStillImageAsynchronouslyFromConnection(videoConnection, completionHandler: { (sampleBuffer, error) -> Void in
            // process the image data (sampleBuffer) here to get an image file we can put in our view

            if (sampleBuffer != nil) {
                let imageData = AVCaptureStillImageOutput.jpegStillImageNSDataRepresentation(sampleBuffer)
                let image = UIImage(data: imageData, scale: 1.0)

                self.fullScreenView.hidden = true
                self.fullScreenView.gestureRecognizers?.forEach(self.fullScreenView.removeGestureRecognizer)
                self.session.stopRunning()

                // save image to the library
                UIImageWriteToSavedPhotosAlbum(image!, nil, nil, nil)

                self.imageViewBackground = UIImageView(frame: self.view.bounds)
                self.imageViewBackground.image = image
                self.imageViewBackground.tag = self.key

                self.view.addSubview(self.imageViewBackground)
            }
        })
    }
}
else {
    preview = true
}
}

我的预览看起来像这样，没关系：

http://img5.fotos-hochladen.net/uploads/bildschirmfotom4s7diaehy.png

但最终看起来是这样的：

http://img5.fotos-hochladen.net/uploads/bildschirmfoto3c2rlwtevf.png

提前致谢！

Answer 1

因为无论您的设备是纵向还是横向，您的 videoConnection 的方向 始终是纵向的。所以你应该在拍摄静态照片之前将 videoConnection 的方向调整到正确的方向

添加如下方法获取当前deviceOrientation的videoOrientation

func videoOrientation(for deviceOrientation: UIDeviceOrientation) -> AVCaptureVideoOrientation {
    switch deviceOrientation {
    case UIDeviceOrientation.portrait:
        return AVCaptureVideoOrientation.portrait
    case UIDeviceOrientation.landscapeLeft:
        return AVCaptureVideoOrientation.landscapeRight
    case UIDeviceOrientation.landscapeRight:
        return AVCaptureVideoOrientation.landscapeLeft
    case UIDeviceOrientation.portraitUpsideDown:
        return AVCaptureVideoOrientation.portraitUpsideDown
    default:
        return AVCaptureVideoOrientation.portrait
    }
}

就在下面一行

if let videoConnection = stillImageOutput.connectionWithMediaType(AVMediaTypeVideo) {

添加以下行

videoConnection.videoOrientation = videoOrientation(for: UIDevice.current.orientation)

注意：如果您的应用仅支持纵向或横向模式，此问题仍然会发生，因为UIDevice.current.orientation 将始终返回支持的方向。为了克服这个问题，您可以使用CoreMotion 来检测设备方向，然后将其传递给videoOrientation(for:) 方法。

希望这会有所帮助:)

Answer 2

我从@Yodagama 得到了答案，但他没有添加如何检测方向

if let photoOutputConnection = self.photoOutput.connection(with: .video) {

                            // USE the below function HERE
    photoOutputConnection.videoOrientation = videoOrientation()
}
    
photoOutput.capturePhoto(with: settings, delegate: self)

检测设备方向的功能：

func videoOrientation() -> AVCaptureVideoOrientation {
    
    var videoOrientation: AVCaptureVideoOrientation!
    
    let orientation: UIDeviceOrientation = UIDevice.current.orientation
    
    switch orientation {
        
    case .faceUp, .faceDown, .unknown:
        
        // let interfaceOrientation = UIApplication.shared.statusBarOrientation
        
        if let interfaceOrientation = UIApplication.shared.windows.first(where: { $0.isKeyWindow })?.windowScene?.interfaceOrientation {
            
            switch interfaceOrientation {
                
            case .portrait, .portraitUpsideDown, .unknown:
                videoOrientation = .portrait
            case .landscapeLeft:
                videoOrientation = .landscapeRight
            case .landscapeRight:
                videoOrientation = .landscapeLeft
            @unknown default:
                videoOrientation = .portrait
            }
        }
        
    case .portrait, .portraitUpsideDown:
        videoOrientation = .portrait
    case .landscapeLeft:
        videoOrientation = .landscapeRight
    case .landscapeRight:
        videoOrientation = .landscapeLeft
    @unknown default:
        videoOrientation = .portrait
    }
    
    return videoOrientation
}

Answer 3

可能的解决方案：将图像保存为 JPEG 而不是 PNG

这是因为 PNG 不存储方向信息。将照片另存为 JPG，它的方向会正确。

使用此代码在拍摄图像后立即将图像转换为 JPG（第二行是此处的操作）：

let image = AVCaptureStillImageOutput.jpegStillImageNSDataRepresentation(sampleBuffer)
let imageData:NSData = UIImageJPEGRepresentation(image, 0.9)! // 0.9 is compression value: 0.0 is most compressed/lowest quality and 1.0 is least compressed/highest quality

来源+更多信息：https://stackoverflow.com/a/34796890/5700898

---

如果这不起作用

我已经在几个地方编辑了你的代码，看看下面的代码现在是否能如你所愿：

// initialize saving photo capabilities
func image(image: UIImage, didFinishSavingWithError error: NSError?, contextInfo:UnsafePointer<Void>) {
        if error == nil {
            print("image saved")
        } else {
            print("save error: \(error?.localizedDescription)")
        }
}

// take a photo
@IBAction func takePhoto(sender: AnyObject) {
self.fullScreenView.hidden = false
self.recordButton.enabled = false
self.takephoto.enabled = false
self.recordButton.hidden = true
self.takephoto.hidden = true

session.startRunning()

// customize the quality level or bitrate of the output photo
session.sessionPreset = AVCaptureSessionPresetPhoto

// add the AVCaptureVideoPreviewLayer to the view and set the view in fullscreen
fullScreenView.frame = view.bounds
videoPreviewLayer.frame = fullScreenView.bounds
fullScreenView.layer.addSublayer(videoPreviewLayer)

// add action to fullScreenView
gestureFullScreenView = UITapGestureRecognizer(target: self, action: #selector(ViewController.takePhoto(_:)))
self.fullScreenView.addGestureRecognizer(gestureFullScreenView)

// add action to myView
gestureView = UITapGestureRecognizer(target: self, action: #selector(ViewController.setFrontpage(_:)))
self.view.addGestureRecognizer(gestureView)

if (preview == true) {
    if let videoConnection = stillImageOutput!.connectionWithMediaType(AVMediaTypeVideo) {
        // code for photo capture goes here...

        stillImageOutput?.captureStillImageAsynchronouslyFromConnection(videoConnection, completionHandler: { (sampleBuffer, error) -> Void in
            // process the image data (sampleBuffer) here to get an image file we can put in our view

            if (sampleBuffer != nil) {
                self.stillImageOutput!.outputSettings = [AVVideoCodecKey: AVVideoCodecJPEG]
        if let videoConnection = self.stillImageOutput!.connectionWithMediaType(AVMediaTypeVideo){
            videoConnection.videoOrientation = self.interfaceToVideoOrientation()
            self.stillImageOutput!.captureStillImageAsynchronouslyFromConnection(videoConnection, completionHandler: {
                (sampleBuffer, error) in
                let imageData = AVCaptureStillImageOutput.jpegStillImageNSDataRepresentation(sampleBuffer)
                let image = UIImage(data: imageData)

                self.fullScreenView.hidden = true
                self.fullScreenView.gestureRecognizers?.forEach(self.fullScreenView.removeGestureRecognizer)
                self.session.stopRunning()

                // save image to the library
                UIImageWriteToSavedPhotosAlbum(image, self, #selector(ViewController.image(_:didFinishSavingWithError:contextInfo:)), nil)

                self.imageViewBackground = UIImageView(frame: self.view.bounds)
                self.imageViewBackground.image = image
                self.imageViewBackground.tag = self.key

                self.view.addSubview(self.imageViewBackground)
            }
        })
    }
}
else {
    preview = true
}
}