我想弄清楚如何在Swift中使用AVFoundation录制视频。我已经创建了一个自定义相机，但我只知道如何使用它拍摄静态图片，我无法弄清楚如何录制视频。希望你能帮我解决这个问题。
我想按住 takePhotoButton 来录制视频，然后预览我预览当前静态照片的位置。你的帮助将真正帮助我继续我的项目。非常感谢！
import UIKit
import AVFoundation
@available(iOS 10.0, *)
class CameraViewController: UIViewController,AVCaptureVideoDataOutputSampleBufferDelegate {
let photoSettings = AVCapturePhotoSettings()
var audioPlayer = AVAudioPlayer()
var captureSession = AVCaptureSession()
var videoDeviceInput: AVCaptureDeviceInput!
var previewLayer = AVCaptureVideoPreviewLayer()
var frontCamera: Bool = false
var captureDevice:AVCaptureDevice!
var takePhoto = false
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
prepareCamera()
}
func prepareCamera() {
captureSession.sessionPreset = AVCaptureSessionPresetPhoto
if let availableDevices = AVCaptureDeviceDiscoverySession(deviceTypes: [.builtInWideAngleCamera], mediaType: AVMediaTypeVideo, position: .back).devices {
captureDevice = availableDevices.first
beginSession()
}
}
func frontCamera(_ front: Bool){
let devices = AVCaptureDevice.devices()
do{
try captureSession.removeInput(AVCaptureDeviceInput(device:captureDevice!))
}catch{
print("Error")
}
for device in devices!{
if((device as AnyObject).hasMediaType(AVMediaTypeVideo)){
if front{
if (device as AnyObject).position == AVCaptureDevicePosition.front {
captureDevice = device as? AVCaptureDevice
do{
try captureSession.addInput(AVCaptureDeviceInput(device: captureDevice!))
}catch{}
break
}
}else{
if (device as AnyObject).position == AVCaptureDevicePosition.back {
captureDevice = device as? AVCaptureDevice
do{
try captureSession.addInput(AVCaptureDeviceInput(device: captureDevice!))
}catch{}
break
}
}
}
}
}
func beginSession () {
do {
let captureDeviceInput = try AVCaptureDeviceInput(device: captureDevice)
if let previewLayer = AVCaptureVideoPreviewLayer(session: captureSession) {
self.previewLayer = previewLayer
containerView.layer.addSublayer(previewLayer as? CALayer ?? CALayer())
self.previewLayer.frame = self.view.layer.frame
self.previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill
previewLayer.connection.videoOrientation = AVCaptureVideoOrientation.portrait
captureSession.startRunning()
let dataOutput = AVCaptureVideoDataOutput()
dataOutput.videoSettings = [(kCVPixelBufferPixelFormatTypeKey as NSString):NSNumber(value:kCVPixelFormatType_32BGRA)]
dataOutput.alwaysDiscardsLateVideoFrames = true
if captureSession.canAddOutput(dataOutput) {
captureSession.addOutput(dataOutput)
photoSettings.isHighResolutionPhotoEnabled = true
photoSettings.isAutoStillImageStabilizationEnabled = true
}
captureSession.commitConfiguration()
let queue = DispatchQueue(label: "com.NightOut.captureQueue")
dataOutput.setSampleBufferDelegate(self, queue: queue)
}
}
@IBAction func takePhoto(_ sender: Any) {
takePhoto = true
photoSettings.isHighResolutionPhotoEnabled = true
photoSettings.isAutoStillImageStabilizationEnabled = true
}
func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputSampleBuffer sampleBuffer: CMSampleBuffer!, from connection: AVCaptureConnection!) {
if takePhoto {
takePhoto = false
if let image = self.getImageFromSampleBuffer(buffer: sampleBuffer) {
let photoVC = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "PhotoVC") as! PhotoPreviewViewController
photoVC.takenPhoto = image
DispatchQueue.main.async {
self.present(photoVC, animated: true, completion: {
self.stopCaptureSession()
})
}
}
}
}
func getImageFromSampleBuffer (buffer:CMSampleBuffer) -> UIImage? {
if let pixelBuffer = CMSampleBufferGetImageBuffer(buffer) {
let ciImage = CIImage(cvPixelBuffer: pixelBuffer)
let context = CIContext()
let imageRect = CGRect(x: 0, y: 0, width: CVPixelBufferGetWidth(pixelBuffer), height: CVPixelBufferGetHeight(pixelBuffer))
if let image = context.createCGImage(ciImage, from: imageRect) {
return UIImage(cgImage: image, scale: UIScreen.main.scale, orientation: .leftMirrored)
}
}
return nil
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
self.captureSession.stopRunning()
}
func stopCaptureSession () {
self.captureSession.stopRunning()
if let inputs = captureSession.inputs as? [AVCaptureDeviceInput] {
for input in inputs {
self.captureSession.removeInput(input)
}
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
@IBAction func DismissButtonAction(_ sender: UIButton) {
UIView.animate(withDuration: 0.1, animations: {
self.DismissButton.transform = CGAffineTransform.identity.scaledBy(x: 0.8, y: 0.8)
}, completion: { (finish) in
UIView.animate(withDuration: 0.1, animations: {
self.DismissButton.transform = CGAffineTransform.identity
})
})
performSegue(withIdentifier: "Segue", sender: nil)
}
}
答案 0 :(得分：4)
要识别按住按钮并释放按钮，可以通过不同方式完成。最简单的方法是为UIControlEvents.TouchUpInside和UIControlEvents.TouchDown添加目标，如下图所示。
aButton.addTarget(self, action: Selector("holdRelease:"), forControlEvents: UIControlEvents.TouchUpInside);
aButton.addTarget(self, action: Selector("HoldDown:"), forControlEvents: UIControlEvents.TouchDown)
//target functions
func HoldDown(sender:UIButton)
{
// Start recording the video
}
func holdRelease(sender:UIButton)
{
// Stop recording the video
}
还有其他方法，例如为按钮添加长按手势识别器或根据识别器状态查看和启动/停止。更多信息可以在另一个SO回答UIButton with hold down action and release action
中找到您需要将AVCaptureMovieFileOutput添加到捕获会话中，并使用startRecordingToOutputFileURL方法启动视频录制。
AVCaptureFileOutputRecordingDelegate方法以识别开始和didFinish录制在HoldDown()方法中使用此代码开始录制
let videoFileOutput = AVCaptureMovieFileOutput() self.captureSession?.addOutput(videoFileOutput) let documentsURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0] as URL let filePath = documentsURL.appendingPathComponent("tempMovie") videoFileOutput.startRecording(toOutputFileURL: filePath, recordingDelegate: self)
停止录制使用vidoeFileOutput.stopRecording()
答案 1 :(得分：0)
您需要使用AVCaptureMovieFileOutput。使用AVCaptureMovieFileOutput
addOutput(_:)添加到捕获会话中
开始录制
您开始使用录制QuickTime影片
startRecording(to:recordingDelegate:)。你需要提供一个 基于文件的URL和委托。 URL不得标识现有的URL 文件，因为电影文件输出不会覆盖现有的 资源。您还必须具有写入指定的权限 地点。代表必须符合AVCaptureFileOutputRecordingDelegate协议，并且必须实现fileOutput(_:didFinishRecordingTo:from:error:)方法
有关详细信息，请参阅docs。