1、實現視頻錄像的幾種方式
- UIImagePickerController
- AVCaptureSession + AVCaptureMovieFileOutput
- AVCaptureSession + AVAssetWriter
UIImagePickerController系統封裝好的UI，直接輸出視頻文件
AVCaptureSession + AVCaptureMovieFileOutput 支持自定義UI，直接輸出視頻文件
AVCaptureSession + AVAssetWriter支持自定義UI，輸出的是視頻幀和音頻幀，需要自己處理，拼接成視頻文件
2、系統封裝好的 UIImagePickerController
2.1 UIImagePickerController方式
是目前集成相機最簡單的方式，但是不知道自定義相機，這是一個封裝了完整視頻捕獲管線和相機 UI 的 view controller。
2.1.1 info.plist 設置
Privacy - Microphone Usage Description 是否允許設備調用您的麥克風？
Privacy - Camera Usage Description 是否允許設備調用您的相機?
2.1.2 是否支持相機錄制
在實例化相機之前，首先要檢查設備是否支持相機錄制：
/// 判斷是否支持錄像
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerController.SourceType.camera) {
if let availableMediaTypes = UIImagePickerController.availableMediaTypes(for: UIImagePickerController.SourceType.camera) {
if !availableMediaTypes.contains("public.movie") {
print("不支持錄像")
return
}
}
}
2.1.3 權限確認
視頻權限和音頻權限確認
/// 視頻權限
AVCaptureDevice.requestAccess(for: AVMediaType.video) {[weak self] (granted) in
guard let weakSelf = self else {
return
}
if !granted {
print("無權限訪問相機")
return
}
// 錄音權限
AVCaptureDevice.requestAccess(for: AVMediaType.audio) {[weak self] (granted) in
guard let weakSelf = self else {
return
}
if !granted {
print("無權限訪問麥克風")
return
}
// 進入錄像頁面
weakSelf.present(weakSelf.pickerController, animated: true, completion: nil)
}
}
2.1.4 創建UIImagePickerController 對象
然后創建一個 UIImagePickerController 對象，設置好代理便于進一步處理錄制好的視頻 (比如存到相冊) 以及對于用戶關閉相機作出響應：
lazy var pickerController: UIImagePickerController = {
let pickerController = UIImagePickerController()
// 設置圖像選取控制器的來源模式為相機模式 相機、相冊
pickerController.sourceType = UIImagePickerController.SourceType.camera
// 設置相機的類型 public.image public.movie
pickerController.mediaTypes = ["public.movie",]
// 設置攝像頭 前、后
pickerController.cameraDevice = UIImagePickerController.CameraDevice.rear;
// 設置攝像頭閃光燈模式
// pickerController.cameraFlashMode = UIImagePickerController.CameraFlashMode.auto
// 設置攝像圖像品質
pickerController.videoQuality = UIImagePickerController.QualityType.typeHigh
// 設置最長攝像時間
pickerController.videoMaximumDuration = 30
// 允許用戶進行編輯
pickerController.allowsEditing = false
// 設置委托對象
pickerController.delegate = self
return pickerController
}()
2.1.5 UIImagePickerControllerDelegate代理的實現
extension RecordVideoViewController: UIImagePickerControllerDelegate, UINavigationControllerDelegate
{
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
let mediaType = info[UIImagePickerController.InfoKey.mediaType] as! String
if mediaType == "public.movie" {
// 獲取視頻文件的url
let mediaURL = info[UIImagePickerController.InfoKey.mediaURL] as! NSURL
// 視頻文件的地址
let pathString = mediaURL.relativePath
print("視頻地址：" + pathString!)
DispatchQueue.global().async {
//判斷能不能保存到相簿
if (UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(pathString!)) {
//保存視頻到相簿
UISaveVideoAtPathToSavedPhotosAlbum(pathString!, self, #selector(self.saveVideo(videoPath:didFinishSavingWithError:contextInfo:)), nil)
}
DispatchQueue.main.async {
picker.dismiss(animated: true, completion: nil)
}
}
}
}
@objc private func saveVideo(videoPath:String, didFinishSavingWithError error: NSError?, contextInfo: AnyObject) {
if error != nil{
print("保存視頻 失敗")
}else{
print("保存視頻 成功")
}
}
}
3、自定義相機 AVFoundation
AVFoundation 中關于視頻捕獲的主要的類是 AVCaptureSession。它負責調配影音輸入與輸出之間的數據流
3.1 AVCaptureSession + AVCaptureMovieFileOutput方式
3.1.1 info.plist 設置
Privacy - Microphone Usage Description 是否允許設備調用您的麥克風？
Privacy - Camera Usage Description 是否允許設備調用您的相機?
3.1.2 權限確認
視頻權限和音頻權限確認
/// 視頻權限
AVCaptureDevice.requestAccess(for: AVMediaType.video) {[weak self] (granted) in
guard let weakSelf = self else {
return
}
if !granted {
print("無權限訪問相機")
return
}
// 錄音權限
AVCaptureDevice.requestAccess(for: AVMediaType.audio) {[weak self] (granted) in
guard let weakSelf = self else {
return
}
if !granted {
print("無權限訪問麥克風")
return
}
}
}
3.1.3 創建AVCaptureSession
使用一個 capture session，你需要先實例化，添加輸入與輸出，設置分辨率，接著啟動從輸入到輸出之間的數據流：
/// 視頻捕獲會話
let captureSession = AVCaptureSession()
3.1.4 添加視頻輸入設備
//MARK: 添加視頻輸入設備
func addInputVideo() {
self.captureSession.beginConfiguration()
let videoDevice = AVCaptureDevice.default(for: AVMediaType.video)!
let videoInput = try? AVCaptureDeviceInput(device: videoDevice)
if self.captureSession.canAddInput(videoInput!) {
self.captureSession.addInput(videoInput!)
}
self.captureSession.commitConfiguration()
}
3.1.5 添加音頻輸入設備
//MARK: 添加音頻輸入設備
func addInputAudio() {
self.captureSession.beginConfiguration()
let audioDevice = AVCaptureDevice.default(for: AVMediaType.audio)
let audioInput = try? AVCaptureDeviceInput(device: audioDevice!)
if self.captureSession.canAddInput(audioInput!) {
self.captureSession.addInput(audioInput!);
}
self.captureSession.commitConfiguration()
}
3.1.6 設置分辨率
//MARK: 設置分辨率
func setPreset() {
self.captureSession.beginConfiguration()
if self.captureSession.canSetSessionPreset(AVCaptureSession.Preset.hd1280x720) {
self.captureSession.sessionPreset = AVCaptureSession.Preset.hd1280x720
}
self.captureSession.commitConfiguration()
}
3.1.7 設置輸出
//MARK: 設置輸出
func setOutput() {
self.captureSession.beginConfiguration()
if let captureConnection = self.fileOutput.connection(with: AVMediaType.video) {
// 防止抖動
if captureConnection.isVideoStabilizationSupported {
captureConnection.preferredVideoStabilizationMode = .auto
}
// 預覽圖層和視頻方向保存一直
captureConnection.videoOrientation = (self.videoLayer.connection?.videoOrientation)!
}
// 視頻時長默認10秒，此設置不受限制
self.fileOutput.movieFragmentInterval = CMTime.invalid
if self.captureSession.canAddOutput(self.fileOutput) {
self.captureSession.addOutput(self.fileOutput)
}
self.captureSession.commitConfiguration()
}
3.1.8 設置顯示采集畫面，并開始采集
/// 攝像頭采集畫面
lazy var videoLayer: AVCaptureVideoPreviewLayer = {
let videoLayer = AVCaptureVideoPreviewLayer(session: self.captureSession)
videoLayer.videoGravity = AVLayerVideoGravity.resizeAspectFill
videoLayer.masksToBounds = true
return videoLayer
}()
//使用AVCaptureVideoPreviewLayer可以將攝像頭的拍攝的實時畫面顯示在ViewController上
DispatchQueue.main.async {
weakSelf.videoLayer.frame = weakSelf.view.bounds
weakSelf.view.layer.addSublayer(weakSelf.videoLayer)
weakSelf.captureSession.startRunning()
//創建按鈕
weakSelf.setUI()
}
3.1.9 開始錄制
//MARK: 開始錄制
@objc func starRecordVideo() {
if !self.isRecording {
//設置錄像的保存地址
let filePath = self.getNewPath(videoTyle: AVFileType.mp4)
let fileURL = URL(fileURLWithPath: filePath)
//啟動視頻編碼輸出
fileOutput.startRecording(to:fileURL, recordingDelegate: self )
//記錄狀態：錄像中...
self.isRecording = true
//開始、結束按鈕顏色改變
self.starButton.backgroundColor = UIColor.lightGray
self.starButton.isEnabled = false
self.stopButton.backgroundColor = UIColor.blue
self.stopButton.isEnabled = true
}
}
3.1.10 結束錄制
//MARK: 結束錄制
@objc func stopRecordVideo() {
if self.isRecording {
//停止視頻編碼輸出
fileOutput.stopRecording()
//記錄狀態：錄像結束
self .isRecording = false
//開始、結束按鈕顏色改變
self.starButton.backgroundColor = UIColor.red
self.starButton.isEnabled = true
self.stopButton.backgroundColor = UIColor.lightGray
self.stopButton.isEnabled = false
}
}
3.1.11 AVCaptureFileOutputRecordingDelegate
//MARK: AVCaptureFileOutputRecordingDelegate
extension RecordVideo2ViewController:AVCaptureFileOutputRecordingDelegate
{
// 開始錄制
func fileOutput(_ output: AVCaptureFileOutput, didStartRecordingTo fileURL: URL, from connections: [AVCaptureConnection]) {
}
// 結束錄制
func fileOutput(_ output: AVCaptureFileOutput, didFinishRecordingTo outputFileURL: URL, from connections: [AVCaptureConnection], error: Error?) {
// 獲取視頻文件大小
self.getVideoSize(videoUrl: outputFileURL)
// 獲取視頻文件時長
self.getVideoLength(videoUrl: outputFileURL)
// 保存相冊一份，便于測試
self.saveVideoToAlbum(videoUrl: outputFileURL)
// 獲取指定時間的幀
self.getImage(videoUrl: outputFileURL, cmtime: CMTimeMake(value: 1, timescale: 1), width: 300)
// 壓縮視頻
let newPath = self.getNewPath(videoTyle: AVFileType.mov)
print(newPath)
self.convertVideo(inputURL: outputFileURL, outputURL: URL(fileURLWithPath: newPath), presetName: AVAssetExportPresetMediumQuality) { (success) in
if success {
print("壓縮成功")
}else{
print("壓縮失敗")
}
}
}
}
3.2 AVCaptureSession + AVAssetWriter方式
對視頻進一步了解，可以使用AVCaptureVideoDataOutput 和 AVCaptureAudioDataOutput來會各自捕獲視頻和音頻的樣本緩存，而不是AVCaptureMovieFileOutpu。
接著我們可以使用他們的代理AVCaptureVideoDataOutputSampleBufferDelegate和AVCaptureAudioDataOutputSampleBufferDelegate，可以對采樣緩沖進行處理 (比如給視頻加濾鏡)，或者保持原樣傳送。
然后使用 AVAssetWriter 對象可以將樣本緩存寫入文件
3.2.1 info.plist 設置
Privacy - Microphone Usage Description 是否允許設備調用您的麥克風？
Privacy - Camera Usage Description 是否允許設備調用您的相機?
3.2.2 權限確認
視頻權限和音頻權限確認
/// 視頻權限
AVCaptureDevice.requestAccess(for: AVMediaType.video) {[weak self] (granted) in
guard let weakSelf = self else {
return
}
if !granted {
print("無權限訪問相機")
return
}
// 錄音權限
AVCaptureDevice.requestAccess(for: AVMediaType.audio) {[weak self] (granted) in
guard let weakSelf = self else {
return
}
if !granted {
print("無權限訪問麥克風")
return
}
}
}
3.2.3 創建AVCaptureSession
使用一個 capture session，你需要先實例化，添加輸入與輸出，設置分辨率，接著啟動從輸入到輸出之間的數據流：
/// 視頻捕獲會話
let captureSession = AVCaptureSession()
3.2.4 添加視頻輸入設備
//MARK: 添加視頻輸入設備
func addInputVideo() {
self.captureSession.beginConfiguration()
let videoDevice = AVCaptureDevice.default(for: AVMediaType.video)!
let videoInput = try? AVCaptureDeviceInput(device: videoDevice)
if self.captureSession.canAddInput(videoInput!) {
self.captureSession.addInput(videoInput!)
}
self.captureSession.commitConfiguration()
}
3.2.5 添加音頻輸入設備
//MARK: 添加音頻輸入設備
func addInputAudio() {
self.captureSession.beginConfiguration()
let audioDevice = AVCaptureDevice.default(for: AVMediaType.audio)
let audioInput = try? AVCaptureDeviceInput(device: audioDevice!)
if self.captureSession.canAddInput(audioInput!) {
self.captureSession.addInput(audioInput!);
}
self.captureSession.commitConfiguration()
}
3.2.6 設置分辨率
//MARK: 設置分辨率
func setPreset() {
self.captureSession.beginConfiguration()
if self.captureSession.canSetSessionPreset(AVCaptureSession.Preset.hd1280x720) {
self.captureSession.sessionPreset = AVCaptureSession.Preset.hd1280x720
}
self.captureSession.commitConfiguration()
}
3.2.7 添加視頻輸出、音頻輸出
//MARK: 添加視頻輸出、音頻輸出
func addOutputVideoAndAudio() {
self.captureSession.beginConfiguration()
self.videoDataOutput.setSampleBufferDelegate(self, queue: self.sessionQueue!)
if self.captureSession.canAddOutput(self.videoDataOutput) {
self.captureSession.addOutput(self.videoDataOutput)
}
self.audioDataOutput.setSampleBufferDelegate(self, queue: self.sessionQueue)
if self.captureSession.canAddOutput(self.audioDataOutput) {
self.captureSession.addOutput(self.audioDataOutput)
}
self.captureSession.commitConfiguration()
}
3.2.8 設置顯示采集畫面，并開始采集
/// 攝像頭采集畫面
lazy var videoLayer: AVCaptureVideoPreviewLayer = {
let videoLayer = AVCaptureVideoPreviewLayer(session: self.captureSession)
videoLayer.videoGravity = AVLayerVideoGravity.resizeAspectFill
videoLayer.masksToBounds = true
return videoLayer
}()
//使用AVCaptureVideoPreviewLayer可以將攝像頭的拍攝的實時畫面顯示在ViewController上
DispatchQueue.main.async {
weakSelf.videoLayer.frame = weakSelf.view.bounds
weakSelf.view.layer.addSublayer(weakSelf.videoLayer)
weakSelf.captureSession.startRunning()
//創建按鈕
weakSelf.setUI()
}
3.2.9 開始錄制
//MARK: 開始錄制
@objc func starRecordVideo() {
if !self.isRecording {
print("開始錄制")
//設置錄像的保存地址
self.videoPath = self.getNewPath(videoTyle: AVFileType.mp4)
print(self.videoPath)
setAssetWriter(videoPath: self.videoPath)
//記錄狀態：錄像中...
self.isRecording = true
//開始、結束按鈕顏色改變
self.starButton.backgroundColor = UIColor.lightGray
self.starButton.isEnabled = false
self.stopButton.backgroundColor = UIColor.blue
self.stopButton.isEnabled = true
}
}
3.2.10 設置AVAssetWrite
//MARK: 設置AssetWrite
func setAssetWriter(videoPath: String) {
//設置錄像的保存地址
let fileURL = URL(fileURLWithPath: videoPath)
if let assetWriter = try? AVAssetWriter.init(url: fileURL, fileType: AVFileType.mp4) {
self.assetWriter = assetWriter
var width = UIScreen.main.bounds.size.height
var height = UIScreen.main.bounds.size.width
//寫入視頻大小
let numPixels = width*height
//每像素比特
let bitsPerPixel:CGFloat = 12.0;
let bitsPerSecond = numPixels * bitsPerPixel;
if (false) // 是否是劉海屏
{
width = UIScreen.main.bounds.size.height - 146;
height = UIScreen.main.bounds.size.width;
}
let compressionProperties = [
// 視頻尺寸*比率，10.1相當于AVCaptureSessionPresetHigh，數值越大，顯示越精細
AVVideoAverageBitRateKey : bitsPerSecond,
// 設置輸出幀率
AVVideoExpectedSourceFrameRateKey : 15,
// 關鍵幀最大間隔，1為每個都是關鍵幀，數值越大壓縮率越高
AVVideoMaxKeyFrameIntervalKey : 15,
// 畫面質量
AVVideoProfileLevelKey : AVVideoProfileLevelH264BaselineAutoLevel
] as [String : Any]
let videoCompressionSettings = [
AVVideoCodecKey : AVVideoCodecH264,
AVVideoWidthKey : width * 2,
AVVideoHeightKey : height * 2,
// AVVideoScalingModeKey : AVVideoScalingModeResizeAspectFill,
AVVideoCompressionPropertiesKey : compressionProperties
] as [String : Any]
self.assetWriterVideoInput = AVAssetWriterInput.init(mediaType: AVMediaType.video, outputSettings: videoCompressionSettings)
//expectsMediaDataInRealTime 必須設為yes，需要從capture session 實時獲取數據
self.assetWriterVideoInput?.expectsMediaDataInRealTime = true
// 音頻設置
let audioCompressionSettings = [
// 每個聲道的比特率
AVEncoderBitRatePerChannelKey : 28000,
// 設置錄音格式
AVFormatIDKey : kAudioFormatMPEG4AAC,
// 設置通道,單聲道，雙聲道 mp3 必須雙聲道
AVNumberOfChannelsKey : 1,
// 設置錄音采樣率，8000是電話采樣率，對于一般錄音已經夠了
AVSampleRateKey : 22050,
// 每個采樣點位數,分為8、16、24、32
AVLinearPCMBitDepthKey: 16,
// 質量
AVEncoderAudioQualityKey: AVAudioQuality.medium
] as [String : Any]
self.assetWriterAudioInput = AVAssetWriterInput.init(mediaType: AVMediaType.audio, outputSettings: audioCompressionSettings)
self.assetWriterAudioInput?.expectsMediaDataInRealTime = true
if self.assetWriter!.canAdd(self.assetWriterVideoInput!) {
self.assetWriter?.add(self.assetWriterVideoInput!)
}
if self.assetWriter!.canAdd(self.assetWriterAudioInput!) {
self.assetWriter?.add(self.assetWriterAudioInput!)
}
self.canWrite = false
} else {
print("加載AVAssetWriter失敗")
}
}
3.2.12 視頻和音頻每一幀處理
extension RecordVideo3ViewController: AVCaptureVideoDataOutputSampleBufferDelegate,AVCaptureAudioDataOutputSampleBufferDelegate
{
func captureOutput(_ output: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) {
autoreleasepool {
if !isRecording {
return
}
if connection == self.videoDataOutput.connection(with: AVMediaType.video) {
objc_sync_enter(self)
self.appendSampleBuffer(sampleBuffer: sampleBuffer, mediaType: AVMediaType.video)
objc_sync_exit(self)
}
if connection == self.audioDataOutput.connection(with: AVMediaType.audio) {
objc_sync_enter(self)
self.appendSampleBuffer(sampleBuffer: sampleBuffer, mediaType: AVMediaType.audio)
objc_sync_exit(self)
}
}
}
func appendSampleBuffer(sampleBuffer:CMSampleBuffer, mediaType:AVMediaType) {
autoreleasepool {
if (!self.canWrite && mediaType == AVMediaType.video) {
print("開始寫入AVAssetWriter")
self.assetWriter?.startWriting()
self.assetWriter?.startSession(atSourceTime: CMSampleBufferGetPresentationTimeStamp(sampleBuffer))
self.canWrite = true
}
//寫入視頻數據
if mediaType == AVMediaType.video {
if self.assetWriterVideoInput!.isReadyForMoreMediaData {
let success = self.assetWriterVideoInput!.append(sampleBuffer)
if !success {
//停止錄像
objc_sync_enter(self)
self.stopRecordVideo()
objc_sync_exit(self)
}
}
}
//寫入視頻數據
if mediaType == AVMediaType.audio {
if self.assetWriterAudioInput!.isReadyForMoreMediaData {
let success = self.assetWriterAudioInput!.append(sampleBuffer)
if !success {
//停止錄像
objc_sync_enter(self)
self.stopRecordVideo()
objc_sync_exit(self)
}
}
}
}
}
}
3.2.13 結束錄制
//MARK: 結束錄制
@objc func stopRecordVideo() {
if self.isRecording {
print("結束錄制")
//停止視頻編碼輸出
if self.assetWriter != nil && self.assetWriter?.status == AVAssetWriter.Status.writing {
self.assetWriter?.finishWriting { [weak self] in
guard let weakSelf = self else {
return
}
weakSelf.canWrite = false
weakSelf.assetWriter = nil
weakSelf.assetWriterAudioInput = nil
weakSelf.assetWriterVideoInput = nil
}
}
//記錄狀態：錄像結束
self .isRecording = false
//開始、結束按鈕顏色改變
self.starButton.backgroundColor = UIColor.red
self.starButton.isEnabled = true
self.stopButton.backgroundColor = UIColor.lightGray
self.stopButton.isEnabled = false
}
}
