Downloading and playing offline HLS Content - iOS 10 - ios

Question

Since iOS 10, Apple has provided the support for downloading HLS (m3u8) video for offline viewing.
My question is: Is it necessary that we can only download HLS when it is being played ? Or we can just download when user press download button and show progress.
Does anyone has implemented this in Objective C version? Actually my previous App is made in Objective C. Now I want to add support for downloading HLS rather than MP4 (previously I was downloading MP4 for offline view).
I am really desperate to this. Please share thoughts or any code if implemented.

Answer 1

I used the apple code guid to download HLS content with the following code:
var configuration: URLSessionConfiguration?
var downloadSession: AVAssetDownloadURLSession?
var downloadIdentifier = "\(Bundle.main.bundleIdentifier!).background"
func setupAssetDownload(videoUrl: String) {
// Create new background session configuration.
configuration = URLSessionConfiguration.background(withIdentifier: downloadIdentifier)
// Create a new AVAssetDownloadURLSession with background configuration, delegate, and queue
downloadSession = AVAssetDownloadURLSession(configuration: configuration!,
assetDownloadDelegate: self,
delegateQueue: OperationQueue.main)
if let url = URL(string: videoUrl){
let asset = AVURLAsset(url: url)
// Create new AVAssetDownloadTask for the desired asset
let downloadTask = downloadSession?.makeAssetDownloadTask(asset: asset,
assetTitle: "Some Title",
assetArtworkData: nil,
options: nil)
// Start task and begin download
downloadTask?.resume()
}
}//end method
func urlSession(_ session: URLSession, assetDownloadTask: AVAssetDownloadTask, didFinishDownloadingTo location: URL) {
// Do not move the asset from the download location
UserDefaults.standard.set(location.relativePath, forKey: "testVideoPath")
}
if you don't understand what's going on, read up about it here:
https://developer.apple.com/library/archive/documentation/AudioVideo/Conceptual/MediaPlaybackGuide/Contents/Resources/en.lproj/HTTPLiveStreaming/HTTPLiveStreaming.html
now you can use the stored HSL content to play the video in AVPlayer with the following code:
//get the saved link from the user defaults
let savedLink = UserDefaults.standard.string(forKey: "testVideoPath")
let baseUrl = URL(fileURLWithPath: NSHomeDirectory()) //app's home directory
let assetUrl = baseUrl.appendingPathComponent(savedLink!) //append the saved link to home path
now use the path to play video in AVPlayer
let avAssest = AVAsset(url: assetUrl)
let playerItem = AVPlayerItem(asset: avAssest)
let player = AVPlayer(playerItem: playerItem) // video path coming from above function
let playerViewController = AVPlayerViewController()
playerViewController.player = player
self.present(playerViewController, animated: true, completion: {
player.play()
})

Answer 2

The only way you can do this is to set up an HTTP server to serve the files locally after you've downloaded them.
The Live playlist uses a sliding-window. You need to periodically reload it after target-duration time and download only the new segments as they appear in the list (they will be removed at a later time).
Here are some related answers: Can IOS devices stream m3u8 segmented video from the local file system using html5 video and phonegap/cordova?

Answer 3

You can easily download an HLS stream with AVAssetDownloadURLSession makeAssetDownloadTask. Have a look at the AssetPersistenceManager in Apples Sample code: https://developer.apple.com/library/content/samplecode/HLSCatalog/Introduction/Intro.html
It should be fairly straight forward to use the Objective C version of the api.

Answer 4

Yes, you can download video stream served over HLS and watch it later.
There is a very straight forward sample app (HLSCatalog) from apple on this. The code is fairly simple. you can find it here - https://developer.apple.com/services-account/download?path=/Developer_Tools/FairPlay_Streaming_Server_SDK_v3.1/FairPlay_Streaming_Server_SDK_v3.1.zip
You can find more about offline HLS streaming here.