Bad playback on IE11

[yairans]

• What version of Shaka Player are you using? v2.0.0-debug
• Are you using the demo app or your own custom app? the demo app
• What did you do? load a custom manifest in IE11 on win8.1
  • What content did you load? clear dash
    • If custom asset, what manifest and license server URIs?
      http://qa-nginx-vod.dev.kaltura.com/dash/p/1091/sp/109100/serveFlavor/entryId/0_rd5ko090/v/2/flavorId/0_,zfgyzbls,q6o5z8f3,5na0i0y6,/forceproxy/true/name/a.mp4.urlset/manifest.mpd
  • What did you expect to happen?
    smooth playback
• What actually happened?
  the playback is jumping (not playing smooth) in first 20 seconds

[ismena]

Hi Yair,
Are you still seeing this issue? We're having trouble getting a repro: when I load the custom manifest you provided, I get a smooth playback. (I also tested in Edge and Win10 just in case).

Could you try a different device to exclude the possibility of the experience being related to a particular machine you're using.

[yairans]

@ismena
I still can reproduce it on IE11+win8.1 with another device as well.
To be more specific, the hiccups take place between second # 17-23

[ismena]

@yairans Could you run "JSON.stringify(shakaDemo.localPlayer_.getStats())" command in the browser console and post the response that you get. This might give me some clues on what's going on with your playback.

[yairans]

@ismena At the problematic seconds (17+) I get the following:
{"width":1280,"height":720,"streamBandwidth":5128249,"decodedFrames":431,"droppedFrames":0,"estimatedBandwidth":58081948.18285577,"playTime":18.536999940872192,"bufferingTime":0.33099985122680664,"switchHistory":[{"timestamp":1475999683.355,"id":3,"type":"audio","fromAdaptation":true},{"timestamp":1475999683.355,"id":1,"type":"video","fromAdaptation":true},{"timestamp":1475999690.352,"id":2,"type":"video","fromAdaptation":true}]}

Is interesting that if I tap the "Load" button then the playback is smooth (unless I reload the demo page itself). I ran the "getStats" command after "Load" tapping and I got the following:
{"width":1280,"height":720,"streamBandwidth":5128249,"decodedFrames":450,"droppedFrames":0,"estimatedBandwidth":49408541.905482955,"playTime":18.773000240325927,"bufferingTime":0.750999927520752,"switchHistory":[{"timestamp":1476000714.476,"id":3,"type":"audio","fromAdaptation":true},{"timestamp":1476000714.476,"id":2,"type":"video","fromAdaptation":true}]}

[joeyparrish]

I see a bandwidth requirement of around 5Mbps, but an estimated bandwidth around 50Mbps. Also, buffering time is low and appears to represent initial buffering only. So we aren't looking at a lack of bandwidth causing a stutter.

I also see no dropped frames, or at least none reported. Dropped frames would indicate a lack of CPU/GPU power to decode & render in real time.

I also see video adaptation about 7 seconds after startup, from 1.5Mbps 720p to 5Mbps 720p. When adapting, v2 would clear 10s ahead of the playhead, so that corresponds to your 17s problem spot.

If you load the stream again, the player already knows how much bandwidth you have and does not need to adapt. This is why there is no problem until you reload the page.

@yairans, we have made some changes recently so that we consider segment boundaries when deciding how much content to clear. We no longer hard-code 10s. This has helped with similar issues on other browsers. Can you please retest with the nightly build? http://nightly.shaka-player-demo.appspot.com/demo/?asset=http://qa-nginx-vod.dev.kaltura.com/dash/p/1091/sp/109100/serveFlavor/entryId/0_rd5ko090/v/2/flavorId/0_,zfgyzbls,q6o5z8f3,5na0i0y6,/forceproxy/true/name/a.mp4.urlset/manifest.mpd

[yairans]

With the nightly I see the same problem earlier from about the 9th second.
For this time I get the following:
{"width":1280,"height":720,"streamBandwidth":5128249,"decodedFrames":209,"droppedFrames":0,"estimatedBandwidth":59546437.453934394,"playTime":8.774999856948852,"bufferingTime":0,"switchHistory":[{"timestamp":1476358179.797,"id":3,"type":"audio","fromAdaptation":true},{"timestamp":1476358179.797,"id":1,"type":"video","fromAdaptation":true},{"timestamp":1476358180.005,"id":2,"type":"video","fromAdaptation":true}]}

[joeyparrish]

Is this the same content from #549? It appears that piece of content doesn't follow DASH interop guidelines, so these two issues may be one and the same. It may not be reasonable to expect that piece of content to play well on any browser.

[joeyparrish]

Closing due to inactivity. @yairans, if this is different content from #549, let us know and we can reopen the investigation.