ios - 使用 AVFoundation Swift 保存视频

Question

您好，我学习了 Jared Davidson 的类(class)，使用 AVFoundation 创建自定义相机 View 并保存图片。 https://www.youtube.com/watch?v=w0O3ZGUS3pk

但是我想录制和保存视频而不是图像。有人可以帮我吗？我确信它很简单，但苹果的文档是用 Objective-C 编写的，我无法解读它。

这是我的代码。谢谢。

import UIKit
import AVFoundation

class ViewController: UIViewController {

    var captureSession = AVCaptureSession()
    var sessionOutput = AVCaptureStillImageOutput()
    var previewLayer = AVCaptureVideoPreviewLayer()


    @IBOutlet var cameraView: UIView!

    override func viewWillAppear(animated: Bool) {

        let devices = AVCaptureDevice.devicesWithMediaType(AVMediaTypeVideo)
        for device in devices {
            if device.position == AVCaptureDevicePosition.Front{


                do{

                    let input = try AVCaptureDeviceInput(device: device as! AVCaptureDevice)

                    if captureSession.canAddInput(input){

                        captureSession.addInput(input)
                        sessionOutput.outputSettings = [AVVideoCodecKey : AVVideoCodecJPEG]

                        if captureSession.canAddOutput(sessionOutput){

                            captureSession.addOutput(sessionOutput)
                            captureSession.startRunning()

                            previewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
                            previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill
                            previewLayer.connection.videoOrientation = AVCaptureVideoOrientation.Portrait
                            cameraView.layer.addSublayer(previewLayer)

                            previewLayer.position = CGPoint(x: self.cameraView.frame.width / 2, y: self.cameraView.frame.height / 2)
                            previewLayer.bounds = cameraView.frame


                        }

                    }

                }
                catch{

                    print("Error")
                }

            }
        }    

    }


    @IBAction func TakePhoto(sender: AnyObject) {

        if let videoConnection = sessionOutput.connectionWithMediaType(AVMediaTypeVideo){

            sessionOutput.captureStillImageAsynchronouslyFromConnection(videoConnection, completionHandler: {
                buffer, error in

                let imageData = AVCaptureStillImageOutput.jpegStillImageNSDataRepresentation(buffer)
                UIImageWriteToSavedPhotosAlbum(UIImage(data: imageData)!, nil, nil, nil)

            })

        }

    }

}

Answer 1

您可以通过创建 AVCaptureMovieFileOutput 并将其添加到您的捕获 session ，并使您的 ViewController 符合 AVCaptureFileOutputRecordingDelegate.

此示例将 5 秒的视频录制到应用程序文档目录中名为“output.mov”的文件中。

class ViewController: UIViewController, AVCaptureFileOutputRecordingDelegate {

    var captureSession = AVCaptureSession()
    var sessionOutput = AVCaptureStillImageOutput()
    var movieOutput = AVCaptureMovieFileOutput()
    var previewLayer = AVCaptureVideoPreviewLayer()

    @IBOutlet var cameraView: UIView!

    override func viewWillAppear(animated: Bool) {
        self.cameraView = self.view

        let devices = AVCaptureDevice.devicesWithMediaType(AVMediaTypeVideo)
        for device in devices {
            if device.position == AVCaptureDevicePosition.Front{


                do{

                    let input = try AVCaptureDeviceInput(device: device as! AVCaptureDevice)

                    if captureSession.canAddInput(input){

                        captureSession.addInput(input)
                        sessionOutput.outputSettings = [AVVideoCodecKey : AVVideoCodecJPEG]

                        if captureSession.canAddOutput(sessionOutput){

                            captureSession.addOutput(sessionOutput)

                            previewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
                            previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill
                            previewLayer.connection.videoOrientation = AVCaptureVideoOrientation.Portrait
                            cameraView.layer.addSublayer(previewLayer)

                            previewLayer.position = CGPoint(x: self.cameraView.frame.width / 2, y: self.cameraView.frame.height / 2)
                            previewLayer.bounds = cameraView.frame


                        }

                        captureSession.addOutput(movieOutput)

                        captureSession.startRunning()

                        let paths = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)
                        let fileUrl = paths[0].URLByAppendingPathComponent("output.mov")
                        try? NSFileManager.defaultManager().removeItemAtURL(fileUrl)
                        movieOutput.startRecordingToOutputFileURL(fileUrl, recordingDelegate: self)

                        let delayTime = dispatch_time(DISPATCH_TIME_NOW, Int64(5 * Double(NSEC_PER_SEC)))
                        dispatch_after(delayTime, dispatch_get_main_queue()) {
                            print("stopping")
                            self.movieOutput.stopRecording()
                        }
                    }

                }
                catch{

                    print("Error")
                }

            }
        }

    }

    func captureOutput(captureOutput: AVCaptureFileOutput!, didFinishRecordingToOutputFileAtURL outputFileURL: NSURL!, fromConnections connections: [AnyObject]!, error: NSError!) {
        print("FINISHED \(error)")
        // save video to camera roll
        if error == nil {
            UISaveVideoAtPathToSavedPhotosAlbum(outputFileURL.path!, nil, nil, nil)
        }
    }

}