swiftavassetavassetimagegenerator

How do I implement AVAssetImageGenerator.copyCGImageAtTime in swift

Thus far I have the following

let assetUrl = NSURL.URLWithString(self.targetVideoString)
let asset: AVAsset = AVAsset.assetWithURL(assetUrl) as AVAsset
let imageGenerator = AVAssetImageGenerator(asset: asset);
let time : CMTime = CMTimeMakeWithSeconds(1.0, 1)
let actualTime : CMTime
let myImage: CGImage =imageGenerator.copyCGImageAtTime(requestedTime: time, actualTime:actualTime, error: <#NSErrorPointer#>)

The last line is where I get lost ... I simply want to grab an image at time 1.0 seconds

Solution

  • The function is declared as

    func copyCGImageAtTime(
    requestedTime: CMTime, 
    actualTime: UnsafeMutablePointer<CMTime>, 
    error outError: NSErrorPointer
) -> CGImage!

    and you have to pass (initialized) CMTime and NSError? variables as "in-out expression" with &:

    let assetUrl = NSURL(string: ...)
let asset: AVAsset = AVAsset.assetWithURL(assetUrl) as AVAsset
let imageGenerator = AVAssetImageGenerator(asset: asset);
let time = CMTimeMakeWithSeconds(1.0, 1)
    
var actualTime : CMTime = CMTimeMake(0, 0)
var error : NSError?
let myImage = imageGenerator.copyCGImageAtTime(
    time, actualTime: &actualTime, error: &error
)

    Note also that your first line

    let assetUrl = NSURL.URLWithString(self.targetVideoString)

    does not compile anymore with the current Xcode 6.1.