Pre-buffering for AVQueuePlayer

Question

Does anyone know if AVQueuePlayer starts buffering the next AVPlayerItem when the current item is about to finish playing?

I know there\'s

Answer 1

I've been experimenting with the AVQueuePlayer using movies provided by a server. In this particular test I set up a queuePlayer with AVPlayerItems initialized with URL's to two different video assets of different types. One is an .mp4-file (progressive download), the other one an .m3u8 http-streaming file. It does act a bit funky, I must say.

Depending on the order in which I queue the files I get quite different behavior. If I start with the .mp4-file, the AVPlayerLayer goes blank and silent when the nextItem starts player (the .m3u8-file). If I change the order and start with the m3u8-file, the AVPlayerLayer goes blank but the audio from the second file plays fine.

My impression, from what I've seen so far, is that the AVQueuePlayer does NOT start downloading the next AVPlayerItem before the current AVPlayerItem has finished playing. But I might be wrong.

To be continued I guess...

Edit: Ok, so I've done some more testing and it seems the next items starts downloading before the last item finishes playing. See post below. Stroke the "NOT"...

Edit2: Adding my explanation here instead, since the comment left me with no formatting options. (Best practice for this is welcome, if this is a bad way to handle answer updates)

Anyhow, I iterated through my itemsArray adding observation of the status property using KVO...

[playerItem addObserver: self forKeyPath:@"status" options: 0 context: NULL];

I also set my controller as the observer of the AVPlayerItem Notification AVPlayerItemDidPlayToEndTimeNotification:

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

Now I could log the status change of the AVPlayerItem, and it turns out the next AVPlayerItem in the queue is logged with a status change AVPlayerItemStatusReadyToPlay before the current item ends playing back.

My conclusion is therefor that the next item in line starts downloading prior to the current item ends.

However! I create an array with AVPlayerItems which I use to create my player. Reading the AVFoundation docs on AVAssets, I get the impression that these download their assets asynchronously, but I'm still uncertain when these downloads are being initiated by the IAPlayerItem. I still have some funky behavior when I add the .m3u8-file to the queue, which makes me wonder if these assets begin downloading at the time of creation (seems a bit strange to me though).