ios - swift 和 CMTimeMake

Question

我尝试捕捉视频:
https://developer.apple.com/library/ios/documentation/AudioVideo/Conceptual/AVFoundationPG/Articles/04_MediaCapture.html#//apple_ref/doc/uid/TP40010188-CH5-SW26

var maxDuration : CMTime = CMTimeMake(seconds, preferredTimeScale)
aMovieFileOutput.maxRecordedDuration = CMTimeMake(seconds, preferredTimeScale)

1 行有错误:使用模块“CMTime”作为类型
2 行有错误:使用未解析的标识符 'CMTimeMake'

我做错了什么？

Answer 1

CMTime 和 CMTimeMake 是在“CoreMedia”模块中定义的，因此您必须

import CoreMedia

然后编译没有问题:

let seconds : Int64 = 10
let preferredTimeScale : Int32 = 1
let aMovieFileOutput = AVCaptureMovieFileOutput()
let maxDuration : CMTime = CMTimeMake(seconds, preferredTimeScale)
aMovieFileOutput.maxRecordedDuration = maxDuration

Swift 3 更新:

let maxDuration = CMTime(seconds: Double(seconds), preferredTimescale: 1)