support playlists with drift between actual PTS and HLS time tracking

[video-dev]

support playlists with drift between actual PTS and HLS time tracking

[matb33]

Below is a hack temporary solution until @mangui has time to implement the above. I emphasize that this is a hack solution -- it works but you need to wait until the looping error event is fired before it recovers, so it's generally slow. It doesn't hurt to keep once the proper drift solution is implemented, as it offers a fallback recovery in case the looping crops up for other potential reasons:

var hls = new Hls();
var video = document.getElementById('your-video-id');

hls.attachVideo(video);

//...

hls.on(Hls.Events.ERROR, function (event, data) {
  if (!data.fatal && data.details === Hls.ErrorDetails.FRAG_LOOP_LOADING_ERROR) {
    seekToNearestBuffered();
  }
});

function seekToNearestBuffered() {
  var pos = video.currentTime,
    closest = null,
    smallestDiff = null,
    start, diff;

  console.log("[hlsjs] attempt to seek to nearest buffered area, currentTime:", pos);

  for (var i = 0; i < video.buffered.length; i++) {
    start = video.buffered.start(i);
    diff = Math.abs(pos - start);
    if (smallestDiff === null || diff < smallestDiff) {
      closest = start;
      smallestDiff = diff;
    }
  }

  if (closest !== null) {
    console.log("[hlsjs] seeking to closest buffered area start:", closest);
    video.currentTime = closest;
  }
}

[mangui]

@matb33 your playlist should work, you can check on drift_refactor branch
@shacharz it should also fix the playback of https://livestream.peer5.com/video/soccer/index.m3u8

[mangui]

closing as implemented

[matb33]

So far this drift fix has been working great. We're running it through a beta period with several users and will let you know if we encounter issues.