SO 上有很多关于视频预加载的主题，但对我来说仍然不是很清楚。
目标:
- 从网络加载视频，给定URL
- 等待视频完全加载
- 立即播放视频(正如我所说，它已经缓冲了 100%)
理想情况下，计算下载速度，预测 f.e 当缓冲 60% 的视频时，我们开始播放，40% 将在播放时缓冲而不会延迟。
我的尝试:
NSURL *url = [NSURL URLWithString:@"video url address here"];
AVURLAsset *avasset = [[AVURLAsset alloc] initWithURL:url options:nil];
AVPlayerItem *item = [[AVPlayerItem alloc] initWithAsset:avasset];
self.player = [[AVPlayer alloc] initWithPlayerItem:item];
self.playerLayer = [AVPlayerLayer playerLayerWithPlayer:self.player];
CGSize size = self.view.bounds.size;
float x = size.width/2.0-202.0;
float y = size.height/2.0 - 100;
self.playerLayer.frame = CGRectMake(x, y, 404, 200);
self.playerLayer.backgroundColor = [UIColor blackColor].CGColor;
[self.view.layer addSublayer:self.playerLayer];
NSString *tracksKey = @"tracks";
[avasset loadValuesAsynchronouslyForKeys:[NSArray arrayWithObject:tracksKey] completionHandler:
^{
dispatch_async(dispatch_get_main_queue(),
^{
NSError *error = nil;
AVKeyValueStatus status = [avasset statusOfValueForKey:tracksKey error:&error];
NSLog(@"Status %d", status);
if (status == AVKeyValueStatusLoaded) {
[self.player play];
}
else {
NSLog(@"The asset's tracks were not loaded:\n%@", [error localizedDescription]);
}
});
}];
}
视频开始播放，连接速度慢时挂断，但如果我们开始播放，比方说 1 分钟后，播放效果很好。
主要问题 - 是否有能力在可以开始并播放到结束时得到通知而不会延迟？
注意:它是 AVFoundation 还是 MPMovieController 并不重要
我假设只能通过单独下载视频，将其存储在本地然后播放来完成。消极方面 - 在下载整个文件之前我们无法开始播放。
最佳答案
您可以对 AVPlayerItem 的 playbackLikelyToKeepUp、playbackBufferEmpty 和 playbackBufferFull 属性进行键值观察，以了解播放器的状态。在 docs 中查看有关这些值何时为真的更详细信息.特别是:
It is possible for playbackLikelyToKeepUp to indicate NO while the property playbackBufferFull indicates YES. In this event the playback buffer has reached capacity but there isn't the statistical data to support a prediction that playback is likely to keep up in the future. It is up to you to decide whether to continue media playback.
关于ios - 预加载视频以立即播放，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/26037132/