How to scrub audio with AVPlayer? - ios

Question

I'm using seekToTime for an AVPlayer. It works fine, however, I'd like to be able to hear audio as I scrub through the video, much like how Final Cut or other video editors work. Just looking for ideas or if I've missed something obvious.

Answer 1

The way to do this is to scrub a simultaneous AVplayer asynchronously alongside the video. I did it this way (in Swift 4):
// create the simultaneous player and feed it the same URL:
let videoPlayer2 = AVPlayer(url: sameUrlAsVideoPlayer!)
videoPlayer2.volume = 5.0
//set the simultaneous player at exactly the same point as the video player.
videoPlayer2.seek(to: sameSeekTimeAsVideoPlayer)
// create a variable(letsScrub)that allows you to activate the audio scrubber when the video is being scrubbed:
var letsScrub: Bool?
//when you are scrubbing the video you will set letsScrub to true:
if letsScrub == true {audioScrub()}
//create this function to scrub audio asynchronously:
func audioScrub() {
DispatchQueue.main.async {
//set the variable to false so the scrubbing does not get interrupted:
self.letsScrub = false
//play the simultaneous player
self.videoPlayer2.play()
//make sure that it plays for at least 0.25 of a second before it stops to get that scrubbing effect:
DispatchQueue.main.asyncAfter(deadline: .now() + 0.25) {
//now that 1/4 of a second has passed (you can make it longer or shorter as you please) - pause the simultaneous player
self.videoPlayer2.pause()
//now move the simultaneous player to the same point as the original videoplayer:
self.videoPlayer2.seek(to: self.sameSeekTimeAsVideoPlayer)
//setting this variable back to true allows the process to be repeated as long as video is being scrubbed:
self.letsScrub = true
}
}
}