CMTime extension to retrieve Seconds and time in String format (HH:mm:ss)

extension CMTime {

    var seconds: Int {
        return Int(CMTimeGetSeconds(self))
    }

    var string: String {
        let value = self.seconds
        let hours = (value % 86400) / 3600
        let minutes = (value % 3600) / 60
        let seconds = (value % 3600) % 60
        return String(format: "%02d:%02d:%02d", hours, minutes, seconds)
    }
}