UICollectionView 视频性能

UICollectionView Video Performance

我有一个用于 Apple TV 的 UICollectionView。最多有 6 个单元格全部显示在同一屏幕上。每个单元格都有不同的循环视频播放。但是,我发现超过 2 个视频会导致视频播放非常不稳定。如何提高播放视频的性能?

class ExerciseCell: UICollectionViewCell {

@IBOutlet private weak var stationNumberLabel: UILabel!
@IBOutlet private weak var exerciseNameLabel: UILabel!

private var looperPlayer:AVPlayerLooper!

var exercise:ExerciseData! {
    didSet {
        self.stationNumberLabel.text = exercise.stationNumber
        self.exerciseNameLabel.text = exercise.exerciseName
        playVideo()
    }
}

private func playVideo()
{
    //if let videoURL = URL(string:self.exercise.videoURL)
    if let videoPath = Bundle.main.path(forResource: self.exercise.videoName, ofType: "mp4")
    {
        //let playerItem = AVPlayerItem(url: videoURL)
        let playerItem = AVPlayerItem(url: URL(fileURLWithPath: videoPath))
        let queuePlayer = AVQueuePlayer(playerItem: playerItem)
        let playerLayer = AVPlayerLayer(player: queuePlayer)

        playerLayer.frame = self.layer.bounds
        playerLayer.videoGravity = .resize
        playerLayer.player = queuePlayer

        self.looperPlayer = AVPlayerLooper(player: queuePlayer, templateItem: playerItem)
        self.layer.insertSublayer(playerLayer, at: 0)

        queuePlayer.volume = 0.0
        queuePlayer.play()
    }
    else
    {
        self.layer.sublayers?.forEach { [=10=].removeFromSuperlayer() }
    }
}}

以上调用自UICollectionViewController

override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell
{
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseIdentifier, for: indexPath) as! ExerciseCell

    cell.exercise = self.exercisesArray[indexPath.row]

    return cell
}

问题是由 1920X1080 的源视频分辨率引起的。降低分辨率解决了问题。