问题 AVAssetReader is fantastic, but I can only see how to use it with a local asset, a file, or I guess a composition, So, assetReader = try AVAssetReader(asset: self.asset) ... assetReader.addOutput(readerOutput) and so on, Say you have an arriving stream (perhaps Apple's examples of .M3U8 files, https://developer.apple.com/streaming/examples/ ) In fact, can AVAssetReader be used for streams? Or only local files? I just plain cannot find this explained anywhere. (Maybe it's obvious if you're