AVPlayer seekToTime: doesn't use buffer

Question

I am developing an application for playing video using HTTP Live Streaming technology.
For this I use AVPlayer which init as follows:

[[AVPlayer alloc] initWithURL:[NSURL URLWithString:VIDEO_URL]];

Then I check the state of the buffer using self.player.currentItem.loadedTimeRanges and display this range on my custom view.

The problem is that when rewinding in an area that is loaded by [self.player seekToTime:timeToSeek toleranceBefore:kCMTimeZero toleranceAfter:kCMTimeZero];, loads the video starts just as if it was not in the buffer.

Hey Pavel - did you figure this out? I'm running into this issue now. I'm testing on a physical device. Did testing on a device remove the issue for you? — rjkaplan, Mar 25 '14 at 17:31
no need to seek, when you use live streaming.. you have to play current stream only right? — Ashish Kakkad, Apr 01 '14 at 05:39
@AshishKakkad - I'm streaming 3/4 minute videos to a device. My problem is that when a user seeks somewhere in the video that they are streaming, the buffer gets cleared. — rjkaplan, May 20 '14 at 23:13

score 3 · Answer 1 · answered Apr 01 '14 at 09:19

First of all, my answer assumes that you are using HTTP Live Streaming for a static m3u8 list, otherwise seeking within the video will not make much sense.

Possible Cause

HTTP Live Streaming uses an m3u style playlist which embeds sub playlists. Each sub-playlist shows different video quality and the AVPlayer chooses which one to use according to the network speed.

But, according to Apple's documentation, when the player initially starts playing it first chooses the first sub-playlist and only after a couple of ts files were played it chooses the appropriate sub-playlist as described above.

So it could be that when you seek to a certain time, the player first tries to play the first sub-list which is not cached.

Suggested Solution

Try the following:

Change the m3u8 stream to have only one sub-stream.
Use a value other than kCMTimeZero for the tolerance, i.e.CMTimeMake(30, 60)
Monitor the network calls to see what exactly it is that the player downloads and when, you could use Charles proxy for example.

If we go with 1st solution then I guess Apple will reject the app. As streaming, the sub-stream will kill the purpose of using HLS videos — Abuzar Amin, Jul 22 '19 at 13:16

score 1 · Answer 2 · answered Apr 01 '14 at 13:02

1

Try to use sample code StitchedStreamPlayer provided in iOS Developer's library for your answer..

answered Apr 01 '14 at 13:02

Ashish Kakkad

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AVPlayer seekToTime: doesn't use buffer

2 Answers2

Possible Cause

Suggested Solution