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预览不显示(AVCaptureVideoPreviewLayer)

video-capture avfoundation video swift ios

0

bcye · 技术社区 · 6 年前

我想先让我的应用程序显示广角相机的相机预览。但我所做的并没有出现。(该应用程序拥有视频和音频权限,目前正在iPhone 7 Plus上测试)

以下是我的会话配置代码:

func configureSession() throws {
    session.beginConfiguration()

    // configure inputs
    let videoDevice = AVCaptureDevice.default(.builtInWideAngleCamera, for: .video, position: .back)
    let audioDevice = AVCaptureDevice.default(.builtInMicrophone, for: .audio, position: .unspecified)
    guard let videoInput = try? AVCaptureDeviceInput(device: videoDevice!), let audioInput = try? AVCaptureDeviceInput(device: audioDevice!), session.canAddInput(videoInput), session.canAddInput(audioInput) else {
        throw CameraError.configurationFailed
    }

    // configure outputs
    let output = AVCaptureMovieFileOutput()
    let previewOutput = AVCaptureVideoDataOutput()
    previewOutput.alwaysDiscardsLateVideoFrames = true
    previewOutput.videoSettings = [kCVPixelBufferPixelFormatTypeKey as String : NSNumber(value: kCVPixelFormatType_32BGRA)]
    guard session.canAddOutput(output) && session.canAddOutput(previewOutput) else {
        throw CameraError.configurationFailed
    }
    session.sessionPreset = .high
    session.addOutput(output)
    session.addOutput(previewOutput)

    session.commitConfiguration()
}

这是 previewLayer

// adds given view as previewView to the session
func configureAsPreview(_ view: UIView) {
    let previewLayer = AVCaptureVideoPreviewLayer(session: session)
    view.layer.addSublayer(previewLayer)
    previewLayer.frame = view.layer.frame
}

它被叫来了 viewDidLoad :

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    if cameraManager.hasPermissionForVideo {
        try! cameraManager.configureSession()
        cameraManager.configureAsPreview(self.previewView)
        cameraManager.startSession()
    } else {
        performSegue(withIdentifier: "presentPermissions", sender: nil)
    }
}

我做错什么了?

谢谢。

1 回复 | 直到 6 年前

1

0

Modo Ltunzher 6 年前

在需要时尝试更新层框架,并使用 bounds 而不是 frame

private var __previewLayer = AVCaptureVideoPreviewLayer? = nil
func configureAsPreview(_ view: UIView) {
    let previewLayer = AVCaptureVideoPreviewLayer(session: session)
    self.view.layer.addSublayer(previewLayer)
    previewLayer.frame = self.view.bounds
    self.__previewLayer = previewLayer
}

override viewDidLayoutSubviews() {
    super.viewDidLayoutSubviews()
    self.__previewLayer?.frame = self.view.bounds
}