Illustration of what I'm trying to do
我试图执行以下操作：
到目前为止，我设法播放音乐，将AVCaptureVideoPreviewLayer显示在不同视图的方形容器中，并将视频保存到相机胶卷。
问题是我几乎找不到一些关于使用AVFoundation的模糊教程，这是我的第一个应用程序，让事情变得非常困难。
我设法做了这些事情，但我仍然不明白AVFoundation是如何运作的。对于初学者来说，文档是模糊的，我还没有找到我特别想要的教程，并且将多个教程组合在一起（并且用Obj C编写）使得这不可能。我的问题如下：
所以我做了准备：
override func viewDidLoad() {
super.viewDidLoad()
// Preset For High Quality
captureSession.sessionPreset = AVCaptureSessionPresetHigh
// Get available devices capable of recording video
let devices = AVCaptureDevice.devicesWithMediaType(AVMediaTypeVideo) as! [AVCaptureDevice]
// Get back camera
for device in devices
{
if device.position == AVCaptureDevicePosition.Back
{
currentDevice = device
}
}
// Set Input
let captureDeviceInput: AVCaptureDeviceInput
do
{
captureDeviceInput = try AVCaptureDeviceInput(device: currentDevice)
}
catch
{
print(error)
return
}
// Set Output
videoFileOutput = AVCaptureMovieFileOutput()
// Configure Session w/ Input & Output Devices
captureSession.addInput(captureDeviceInput)
captureSession.addOutput(videoFileOutput)
// Show Camera Preview
cameraPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
view.layer.addSublayer(cameraPreviewLayer!)
cameraPreviewLayer?.videoGravity = AVLayerVideoGravityResizeAspectFill
let width = view.bounds.width*0.85
cameraPreviewLayer?.frame = CGRectMake(0, 0, width, width)
// Bring Record Button To Front
view.bringSubviewToFront(recordButton)
captureSession.startRunning()
// // Bring Message To Front
// view.bringSubviewToFront(messageView)
// view.bringSubviewToFront(messageText)
// view.bringSubviewToFront(messageImage)
}
然后当我按下录制按钮时：
@IBAction func capture(sender: AnyObject) {
if !isRecording
{
isRecording = true
UIView.animateWithDuration(0.5, delay: 0.0, options: [.Repeat, .Autoreverse, .AllowUserInteraction], animations: { () -> Void in
self.recordButton.transform = CGAffineTransformMakeScale(0.5, 0.5)
}, completion: nil)
let outputPath = NSTemporaryDirectory() + "output.mov"
let outputFileURL = NSURL(fileURLWithPath: outputPath)
videoFileOutput?.startRecordingToOutputFileURL(outputFileURL, recordingDelegate: self)
}
else
{
isRecording = false
UIView.animateWithDuration(0.5, delay: 0, options: [], animations: { () -> Void in
self.recordButton.transform = CGAffineTransformMakeScale(1.0, 1.0)
}, completion: nil)
recordButton.layer.removeAllAnimations()
videoFileOutput?.stopRecording()
}
}
录制视频后：
func captureOutput(captureOutput: AVCaptureFileOutput!, didFinishRecordingToOutputFileAtURL outputFileURL: NSURL!, fromConnections connections: [AnyObject]!, error: NSError!) {
let outputPath = NSTemporaryDirectory() + "output.mov"
if UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(outputPath)
{
UISaveVideoAtPathToSavedPhotosAlbum(outputPath, self, nil, nil)
// Show Success Message
UIView.animateWithDuration(0.4, delay: 0, options: [], animations: {
self.messageView.alpha = 0.8
}, completion: nil)
UIView.animateWithDuration(0.4, delay: 0, options: [], animations: {
self.messageText.alpha = 1.0
}, completion: nil)
UIView.animateWithDuration(0.4, delay: 0, options: [], animations: {
self.messageImage.alpha = 1.0
}, completion: nil)
// Hide Message
UIView.animateWithDuration(0.4, delay: 1, options: [], animations: {
self.messageView.alpha = 0
}, completion: nil)
UIView.animateWithDuration(0.4, delay: 1, options: [], animations: {
self.messageText.alpha = 0
}, completion: nil)
UIView.animateWithDuration(0.4, delay: 1, options: [], animations: {
self.messageImage.alpha = 0
}, completion: nil)
}
}
那么我需要做些什么来解决这个问题呢？我一直在搜索和查看教程，但我无法弄明白......我读到了关于添加水印的内容，我发现它与在视频上添加CALayers有关。但显然我无法做到这一点，因为我甚至不知道如何制作视频方块并添加音频。
答案 0 :(得分：3)
一些事情：
就音频而言，您正在添加视频（相机）输入，但没有音频输入。这样做是为了获得声音。
let audioInputDevice = AVCaptureDevice.defaultDeviceWithMediaType(AVMediaTypeAudio)
do {
let input = try AVCaptureDeviceInput(device: audioInputDevice)
if sourceAVFoundation.captureSession.canAddInput(input) {
sourceAVFoundation.captureSession.addInput(input)
} else {
NSLog("ERROR: Can't add audio input")
}
} catch let error {
NSLog("ERROR: Getting input device: \(error)")
}
要使视频正方形，您将不得不考虑使用AVAssetWriter而不是AVCaptureFileOutput。这样更复杂，但你获得了更多的权力＆＃34;。你已经创建了一个很棒的AVCaptureSession，为了连接AssetWriter，你需要做这样的事情：
let fileManager = NSFileManager.defaultManager()
let urls = fileManager.URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)
guard let documentDirectory: NSURL = urls.first else {
print("Video Controller: getAssetWriter: documentDir Error")
return nil
}
let local_video_name = NSUUID().UUIDString + ".mp4"
self.videoOutputURL = documentDirectory.URLByAppendingPathComponent(local_video_name)
guard let url = self.videoOutputURL else {
return nil
}
self.assetWriter = try? AVAssetWriter(URL: url, fileType: AVFileTypeMPEG4)
guard let writer = self.assetWriter else {
return nil
}
//TODO: Set your desired video size here!
let videoSettings: [String : AnyObject] = [
AVVideoCodecKey : AVVideoCodecH264,
AVVideoWidthKey : captureSize.width,
AVVideoHeightKey : captureSize.height,
AVVideoCompressionPropertiesKey : [
AVVideoAverageBitRateKey : 200000,
AVVideoProfileLevelKey : AVVideoProfileLevelH264Baseline41,
AVVideoMaxKeyFrameIntervalKey : 90,
],
]
assetWriterInputCamera = AVAssetWriterInput(mediaType: AVMediaTypeVideo, outputSettings: videoSettings)
assetWriterInputCamera?.expectsMediaDataInRealTime = true
writer.addInput(assetWriterInputCamera!)
let audioSettings : [String : AnyObject] = [
AVFormatIDKey : NSInteger(kAudioFormatMPEG4AAC),
AVNumberOfChannelsKey : 2,
AVSampleRateKey : NSNumber(double: 44100.0)
]
assetWriterInputAudio = AVAssetWriterInput(mediaType: AVMediaTypeAudio, outputSettings: audioSettings)
assetWriterInputAudio?.expectsMediaDataInRealTime = true
writer.addInput(assetWriterInputAudio!)
一旦你设置了AssetWriter ......然后连接视频和音频的一些输出
let bufferAudioQueue = dispatch_queue_create("audio buffer delegate", DISPATCH_QUEUE_SERIAL)
let audioOutput = AVCaptureAudioDataOutput()
audioOutput.setSampleBufferDelegate(self, queue: bufferAudioQueue)
captureSession.addOutput(audioOutput)
// Always add video last...
let videoOutput = AVCaptureVideoDataOutput()
videoOutput.setSampleBufferDelegate(self, queue: bufferVideoQueue)
captureSession.addOutput(videoOutput)
if let connection = videoOutput.connectionWithMediaType(AVMediaTypeVideo) {
if connection.supportsVideoOrientation {
// Force recording to portrait
connection.videoOrientation = AVCaptureVideoOrientation.Portrait
}
self.outputConnection = connection
}
captureSession.startRunning()
最后，您需要捕获缓冲区并处理这些内容...确保您的类成为AVCaptureVideoDataOutputSampleBufferDelegate和AVCaptureAudioDataOutputSampleBufferDelegate
的委托//MARK: Implementation for AVCaptureVideoDataOutputSampleBufferDelegate, AVCaptureAudioDataOutputSampleBufferDelegate
func captureOutput(captureOutput: AVCaptureOutput!, didOutputSampleBuffer sampleBuffer: CMSampleBuffer!, fromConnection connection: AVCaptureConnection!) {
if !self.isRecordingStarted {
return
}
if let audio = self.assetWriterInputAudio where connection.audioChannels.count > 0 && audio.readyForMoreMediaData {
dispatch_async(audioQueue!) {
audio.appendSampleBuffer(sampleBuffer)
}
return
}
if let camera = self.assetWriterInputCamera where camera.readyForMoreMediaData {
dispatch_async(videoQueue!) {
camera.appendSampleBuffer(sampleBuffer)
}
}
}
有一些缺失的部分，但希望这足以让你与文档一起弄明白。
最后，如果你想添加水印，有很多方法可以实时完成，但一种可能的方法是修改sampleBuffer然后将水印写入图像。您将在StackOverflow上找到处理该问题的其他问题。