使用AVFoundation AVPlayer循环播放视频？

Question

在AVFoundation中有一种相对简单的循环视频方式吗？

我已经创建了我的AVPlayer和AVPlayerLayer:

avPlayer = [[AVPlayer playerWithURL:videoUrl] retain];
avPlayerLayer = [[AVPlayerLayer playerLayerWithPlayer:avPlayer] retain];

avPlayerLayer.frame = contentView.layer.bounds;
[contentView.layer addSublayer: avPlayerLayer];

然后我播放我的视频:

[avPlayer play];

视频播放正常但最后停止播放.使用MPMoviePlayerController,您只需将其repeatMode属性设置为正确的值即可.AVPlayer似乎没有类似的属性.似乎没有一个回调可以告诉我什么时候电影结束所以我可以寻找开头并再次播放它.

我没有使用MPMoviePlayerController,因为它有一些严重的限制.我希望能够一次播放多个视频流.

Answer 1

玩家结束时可以获得通知.校验AVPlayerItemDidPlayToEndTimeNotification

设置播放器时:

ObjC

  avPlayer.actionAtItemEnd = AVPlayerActionAtItemEndNone; 

  [[NSNotificationCenter defaultCenter] addObserver:self
                                           selector:@selector(playerItemDidReachEnd:)
                                               name:AVPlayerItemDidPlayToEndTimeNotification
                                             object:[avPlayer currentItem]];

这样可以防止玩家在结束时暂停.

在通知中:

- (void)playerItemDidReachEnd:(NSNotification *)notification {
    AVPlayerItem *p = [notification object];
    [p seekToTime:kCMTimeZero];
}

这将回放电影.

不要忘记在释放播放器时取消注册通知.

迅速

avPlayer?.actionAtItemEnd = .none

NotificationCenter.default.addObserver(self,
                                       selector: #selector(playerItemDidReachEnd(notification:)),
                                       name: .AVPlayerItemDidPlayToEndTime,
                                       object: avPlayer?.currentItem)

@objc func playerItemDidReachEnd(notification: Notification) {
    if let playerItem = notification.object as? AVPlayerItem {
        playerItem.seek(to: kCMTimeZero)
    }
}

Answer 2

如果它有帮助,在iOS/tvOS 10中,有一个新的AVPlayerLooper()可用于创建无缝的视频循环(Swift):

player = AVQueuePlayer()
playerLayer = AVPlayerLayer(player: player)
playerItem = AVPlayerItem(url: videoURL)
playerLooper = AVPlayerLooper(player: player, templateItem: playerItem)
player.play()    

这是在WWDC 2016的"AVFoundation Playback的进展"中提出的:https: //developer.apple.com/videos/play/wwdc2016/503/

即使使用这段代码,在我向Apple提交错误报告并获得此回复之前,我还是有一个打嗝:

电影持续时间长于音频/视频轨道的电影文件是问题.FigPlayer_File正在禁用无间隙转换,因为音轨编辑比电影持续时间短(15.682 vs 15.787).

您需要修复影片文件以使影片持续时间和轨道持续时间长度相同,或者您可以使用AVPlayerLooper的时间范围参数(设置时间范围从0到音轨的持续时间)

事实证明,Premiere一直在导出文件的音轨长度与视频略有不同.在我的情况下,完全删除音频是很好的,这解决了问题.

Answer 3

在Swift中:

当玩家结束时你可以获得通知...检查AVPlayerItemDidPlayToEndTimeNotification

设置播放器时:

avPlayer.actionAtItemEnd = AVPlayerActionAtItemEnd.None

NSNotificationCenter.defaultCenter().addObserver(self, 
                                                 selector: "playerItemDidReachEnd:", 
                                                 name: AVPlayerItemDidPlayToEndTimeNotification, 
                                                 object: avPlayer.currentItem)

这样可以防止玩家在结束时暂停.

在通知中:

func playerItemDidReachEnd(notification: NSNotification) {
    if let playerItem: AVPlayerItem = notification.object as? AVPlayerItem {
        playerItem.seekToTime(kCMTimeZero)
    }
}

Swift3

NotificationCenter.default.addObserver(self,
    selector: #selector(PlaylistViewController.playerItemDidReachEnd),
     name: NSNotification.Name.AVPlayerItemDidPlayToEndTime,
     object: avPlayer?.currentItem)

这将回放电影.

不要忘记在释放播放器时取消注册通知.

Answer 4

以下是我为防止暂停打嗝问题而采取的措施:

迅速:

NotificationCenter.default.addObserver(forName: .AVPlayerItemDidPlayToEndTime,
                                       object: nil,
                                       queue: nil) { [weak self] note in
                                        self?.avPlayer.seek(to: kCMTimeZero)
                                        self?.avPlayer.play()
}

目标C:

__weak typeof(self) weakSelf = self; // prevent memory cycle
NSNotificationCenter *noteCenter = [NSNotificationCenter defaultCenter];
[noteCenter addObserverForName:AVPlayerItemDidPlayToEndTimeNotification
                        object:nil
                         queue:nil
                    usingBlock:^(NSNotification *note) {
                        [weakSelf.avPlayer seekToTime:kCMTimeZero];
                        [weakSelf.avPlayer play];
                    }];

注意:我没有使用,avPlayer.actionAtItemEnd = AVPlayerActionAtItemEndNone因为它不需要.

Answer 5

斯威夫特 5：

我对之前的答案做了一些细微的调整，比如在将 playerItem 添加到队列之前将其添加到 playerLayer。

let playerItem = AVPlayerItem(url: url)
let player = AVQueuePlayer(playerItem: playerItem)
let playerLayer = AVPlayerLayer(player: player)

playerLooper = AVPlayerLooper(player: player, templateItem: playerItem)

playerLayer.frame = cell.eventImage.bounds
playerLayer.videoGravity = AVLayerVideoGravity.resizeAspectFill

// Add the playerLayer to a UIView.layer

player.play()

并让 playerLooper 成为你的 UIViewController 的一个属性，否则视频只能播放一次。