使用Swift在相机上设置相机焦点
在swift中使用相机的API似乎是一个不同的，我很难在一个点上集中相机。 当用户点击屏幕时，我想让相机专注于这一点
这是我的代码：
func focusCamera(point:CGPoint) { var screenRect:CGRect = bounds var focusX = Float(point.x/screenRect.width) var focusY = Float(point.y/screenRect.height) _currentDevice.lockForConfiguration(nil) _currentDevice.setFocusModeLockedWithLensPosition(focusX) { time in self._currentDevice.unlockForConfiguration() } _currentDevice.setFocusModeLockedWithLensPosition(focusY) { time in self._currentDevice.unlockForConfiguration() } } 但它似乎没有工作。
任何build议都比欢迎！
@ryantxr更新了Swift 3的答案：
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) { let screenSize = videoView.bounds.size if let touchPoint = touches.first { let x = touchPoint.location(in: videoView).y / screenSize.height let y = 1.0 - touchPoint.location(in: videoView).x / screenSize.width let focusPoint = CGPoint(x: x, y: y) if let device = captureDevice { do { try device.lockForConfiguration() device.focusPointOfInterest = focusPoint //device.focusMode = .continuousAutoFocus device.focusMode = .autoFocus //device.focusMode = .locked device.exposurePointOfInterest = focusPoint device.exposureMode = AVCaptureExposureMode.continuousAutoExposure device.unlockForConfiguration() } catch { // just ignore } } } }
@Code for Swift 2更新了答案。
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) { let screenSize = videoView.bounds.size if let touchPoint = touches.first { let x = touchPoint.locationInView(videoView).y / screenSize.height let y = 1.0 - touchPoint.locationInView(videoView).x / screenSize.width let focusPoint = CGPoint(x: x, y: y) if let device = captureDevice { do { try device.lockForConfiguration() device.focusPointOfInterest = focusPoint //device.focusMode = .ContinuousAutoFocus device.focusMode = .AutoFocus //device.focusMode = .Locked device.exposurePointOfInterest = focusPoint device.exposureMode = AVCaptureExposureMode.ContinuousAutoExposure device.unlockForConfiguration() } catch { // just ignore } } } }
这个问题也许是iOS重复的重点 ，我发布了这个（希望明确的）解决scheme，为我工作：
使用videoView: UIView显示video，以及cameraDevice: AVCaptureDevice ，以下似乎适用于我：
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) { var touchPoint = touches.first as! UITouch var screenSize = videoView.bounds.size var focusPoint = CGPoint(x: touchPoint.locationInView(videoView).y / screenSize.height, y: 1.0 - touchPoint.locationInView(videoView.x / screenSize.width) if let device = cameraDevice { if(device.lockForConfiguration(nil)) { device.focusPointOfInterest = focusPoint device.focusMode = AVCaptureFocusMode.ContinuousAutoExposure device.exposurePointOfInterest = focusPoint device.exposureMode = AVCaptureExposureMode.ContinuousAutoExposure device.unlockForConfiguration() } } }
请注意，我必须交换x和y坐标，并将x坐标从1重新映射到0，而不是0到1 – 不知道为什么应该是这种情况，但似乎有必要让它正常工作（尽pipe它有点棘手来testing它）。
Swift 2.0
if let device = captureDevice { do { try device.lockForConfiguration() device.focusPointOfInterest = focusPoint device.focusMode = AVCaptureFocusMode.ContinuousAutoFocus device.exposurePointOfInterest = focusPoint device.exposureMode = AVCaptureExposureMode.ContinuousAutoExposure } catch let error as NSError { print(error.localizedDescription) } }
我使用AVFoundation库和相机pipe理器的包装。 我正在共享代码示例。 你可以调整你的项目。 顺便说一下，您无法使用前置摄像头对相机进行对焦。 它不支持它。 您只能调整前置摄像头的曝光。 通过罕见的相机，你可以做到这一点。
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) { let screenSize = cameraView.bounds.size let frameSize:CGSize = view.frame.size if let touchPoint = touches.first { var location:CGPoint = touchPoint.locationInView(cameraView) if cameraManager.cameraDevice == .Front { print("Front camera is used") location.x = frameSize.width - location.x; } else { print("Back camera is used") } let x = location.x / frameSize.width let y = 1.0 - (location.x / frameSize.width) let focusPoint = CGPoint(x: x, y: y) print("POINT : X: \(x), Y: \(y)") let captureDevice = (AVCaptureDevice.devicesWithMediaType(AVMediaTypeVideo) as! [AVCaptureDevice]).filter{$0.position == .Back}.first if let device = captureDevice { do { try device.lockForConfiguration() let support:Bool = device.focusPointOfInterestSupported if support { print("focusPointOfInterestSupported: \(support)") device.focusPointOfInterest = focusPoint // device.focusMode = .ContinuousAutoFocus device.focusMode = .AutoFocus // device.focusMode = .Locked device.unlockForConfiguration() print("Focus point was set successfully") } else{ print("focusPointOfInterestSupported is not supported: \(support)") } } catch { // just ignore print("Focus point error") } } } }
更好的解决scheme，因为它适用于所有的videoGravity模式，当预览图层纵横比与设备比例不同时：
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) { guard let touchPoint = touches.first else { return } // precondition: the videoView contains the previewLayer, and the frames of the two are being kept equal let touchPointInPreviewLayer = touchPoint.location(in: videoView) let focusPoint = previewLayer.captureDevicePointOfInterest(for: touchPointInPreviewLayer) // etc }
结果很简单：
_currentDevice.lockForConfiguration(nil) _currentDevice.focusPointOfInterest = tap.locationInView(self) _currentDevice.unlockForConfiguration()