1238862 - [TV][Seamless experience] The total length of video should not be 00:00

Status: VERIFIED FIXED

(Firefox OS Graveyard :: Gaia::TV, defect)

Description

[Cynthia Tang [:cynthiatang]]

STR: 
 1. Receive the request for the cast video (Real TV)
 2. Check the total length of video 

Expect result:
 - The total length of video should not be 00:00

Actual Result:
 - The total length of video is 00:00

Comment 1

[Cynthia Tang [:cynthiatang]]

Hi Fischer,
Could you please update the analytical results? Thank you!

Comment 2

[Kilik Kuo [:kikuo] (inactive)]

More information.
From app side. The logic of JS code is like.

console.log(video.duration)   // called on evt 'durationchange' received. value will be NaN.
...
console.log("metadataloaded") // called on evt 'loadedmetadata' received.
...
console.log(video.duration)   // called on evt 'durationchange' received. value will be displayed correctly.

The first 'durationchange' & 'loadedmetadata' is fired from [1],[2].
According to w3c spec [3].
===========
...
The user agent must determine the duration of the media resource before playing any part of the media data and before setting readyState to a value equal to or greater than HAVE_METADATA, even if doing so requires fetching multiple parts of the resource.
...
===========

And the 'readyState' is set here [4]. So that, app(js) should be able to obtain correct duration when the 1st 'durationchange' evt arrived.
The duration is obtained from this call [5], and mDecoder should be responsible of providing it.


[1] https://dxr.mozilla.org/mozilla-central/rev/ad1f85f172b7302bef0fa9780df8e2b962780ac6/dom/html/HTMLMediaElement.cpp#3391
[2] https://dxr.mozilla.org/mozilla-central/rev/ad1f85f172b7302bef0fa9780df8e2b962780ac6/dom/html/HTMLMediaElement.cpp#3395
[3] https://www.w3.org/TR/html5/embedded-content-0.html#dom-media-duration
[4] https://dxr.mozilla.org/mozilla-central/rev/ad1f85f172b7302bef0fa9780df8e2b962780ac6/dom/html/HTMLMediaElement.cpp#3389
[5] https://dxr.mozilla.org/mozilla-central/rev/ad1f85f172b7302bef0fa9780df8e2b962780ac6/dom/html/HTMLMediaElement.cpp#1623


Fischer, could you provide js code for more detail.

Comment 3

[Fischer [:Fischer]]

In fling_player.js [1], the fling player get and show the video duration at the loadedmetadata event.

However, the video duration is NaN at the loadedmetadata event so 00:00 is displayed.

We have to wait to get the vaild video duration when the durationchange event fired afterwards.

[1] https://github.com/mozilla-b2g/gaia/blob/v2.5/tv_apps/fling-player/js/fling_player.js#L386

Comment 4

[GitHub Autolander Bot]

Attachment: [gaia] Fischer-L:bug_1238862-fling-player-duration-0 > mozilla-b2g:master

Comment 5

[Fischer [:Fischer]]

Comment on attachment 8709363 [details] [review]
[gaia] Fischer-L:bug_1238862-fling-player-duration-0 > mozilla-b2g:master

@Rex,

On real TV, video duration is NaN at the loadedmetadate event so 00:00 is displayed.
And valid duration would be available at the durationchange event dispatched later.
To workaround this NaN duration issue, this patch listens to the durationchange event to update video duration info.

Thank you

Comment 6

[KM Lee [:rexboy] (inactivate after Sep. 22)]

Comment on attachment 8709363 [details] [review]
[gaia] Fischer-L:bug_1238862-fling-player-duration-0 > mozilla-b2g:master

Looks good to me.

Comment 7

[Fischer [:Fischer]]

Land to master: https://github.com/mozilla-b2g/gaia/commit/b1b2bf885e99480a8994733fe64fb71fc8e45bc0
Test: https://github.com/mozilla-b2g/gaia/commit/b1b2bf885e99480a8994733fe64fb71fc8e45bc0

Comment 8

[Fischer [:Fischer]]

Comment on attachment 8709363 [details] [review]
[gaia] Fischer-L:bug_1238862-fling-player-duration-0 > mozilla-b2g:master

[Approval Request Comment]
[Bug caused by] (feature/regressing bug #): 1238862
[User impact] if declined: No confirmation to exit by pressing back key
[Testing completed]: Yes
[Risk to taking this patch] (and alternatives if risky): Low
[String changes made]: None

Comment 9

[Fischer [:Fischer]]

Comment on attachment 8709363 [details] [review]
[gaia] Fischer-L:bug_1238862-fling-player-duration-0 > mozilla-b2g:master

[Approval Request Comment]
[Bug caused by] (feature/regressing bug #): 1238862
[User impact] if declined: The video duration would be 00:00
[Testing completed]: Yes
[Risk to taking this patch] (and alternatives if risky): Low
[String changes made]: None

Comment 10

[Josh Cheng [:josh]]

Comment on attachment 8709363 [details] [review]
[gaia] Fischer-L:bug_1238862-fling-player-duration-0 > mozilla-b2g:master

Approve for TV 2.5

Comment 11

[Carsten Book [:Tomcat]]

for 2.5 https://github.com/mozilla-b2g/gaia/commit/fd1ea139c137a92e1bdb702da73efd0770c92f5b

Comment 12

[Cynthia Tang [:cynthiatang]]

Verify:

========= Master: Passed ===================
gaia:
https://github.com/mozilla-b2g/gaia/commit/77c0e08caa0dda8c6e50f6e7cbad9f79b320a3b0
gecko:
https://hg.mozilla.org/mozilla-central/rev/a1b94785b48437662c696c9143ed92639e9617b2

========= v2.5: Passed ===================
gaia:
https://github.com/mozilla-b2g/gaia/commit/8a0d9deb2cd47df25750ed2c6820909e4feac3bb
gecko:
https://hg.mozilla.org/releases/mozilla-b2g44_v2_5/rev/ae919160ce8c6a6e9c6d86017b02e1345dea382d
mulet:
https://hg.mozilla.org/releases/mozilla-b2g44_v2_5/rev/ae919160ce8c6a6e9c6d86017b02e1345dea382d