AVAssetResourceLoaderDelegate方法不在设备上工作 [英] AVAssetResourceLoaderDelegate methods not working on device

问题描述

我一直在使用简单的 AVPlayer 来播放加密的 HLS 媒体。

I have been working on a simple AVPlayer to play encrypted HLS media.

我使用 AVAssetResourceLoaderDelegate 来处理密钥检索过程，以便可以使用有效密钥播放加密媒体。

I am using the AVAssetResourceLoaderDelegate to handle the key retrieving process so the encrypted media can be played with a valid key.

该程序在模拟器上完美运行，但它在设备上完全不起作用。

The program works perfectly on simulator, but it doesn't work at all on device.

这里是代码：

- (void) playUrlByAVPlayer:(NSString *) videoUrl
{
    NSURL *streamURL = [NSURL URLWithString:videoUrl];

    AVURLAsset *asset = [AVURLAsset URLAssetWithURL:streamURL options:nil];

    [asset.resourceLoader setDelegate:self queue:dispatch_get_main_queue()];

    self.playerItem = [AVPlayerItem playerItemWithAsset:asset];                           
    self.player = [AVPlayer playerWithPlayerItem:self.playerItem];

    self.playerLayer = [AVPlayerLayer playerLayerWithPlayer:self.player];
    [self.playerLayer setFrame:self.view.frame];
    [self.view.layer addSublayer:self.playerLayer];

    [self.player play];
}

经过一些调试后，我意识到委托方法在设备上从未调用过shouldWaitForLoadingOfRequestedResource 。

After some debugging, I realized that the delegate method shouldWaitForLoadingOfRequestedResource was never called on device.

我已阅读其他相关问题：

I have read other relevant questions:

未调用AVAssetResourceLoaderDelegate

AVAssetResourceLoaderDelegate - 仅请求前两个字节？

我尝试将所有代码包含在 dispatch_async ， dispatch_get_main_queue 块中，但没有运气解决我的问题。

and I tried enclosing all codes within a dispatch_async, dispatch_get_main_queue block but there's no luck on solving mine.

目前我上面的代码没有包含在任何调度队列块中。

Currently my codes above are not enclosed by any dispatch queue blocks.

关于问题？

推荐答案

如果你看看Apple的例子在显示bipbop.m3u8 HLS播放的代码中，您将看到他们正在使用掩码进行真实的http请求：http：/host/bipbop.m3u8=>custom_scheme：/host/bipbop.m3u8
相同应该使用播放列表子资源制作技巧。

If you take a look on Apple example code where they show bipbop.m3u8 HLS playback you will see that they are using masks for real http requests: "http:/host/bipbop.m3u8" => "custom_scheme:/host/bipbop.m3u8" Same trick should be made with playlist subresources.

否则avplayer会忽略AVAssetResourceLoaderDelegate并直接加载数据。

Otherwise avplayer ignores AVAssetResourceLoaderDelegate and load data directly.

你需要实现某种映射：

NSString* videoUrl = @"fake_scheme://host/video.m3u8";
NSURL *streamURL = [NSURL URLWithString:videoUrl];

这篇关于AVAssetResourceLoaderDelegate方法不在设备上工作的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！