Re: WebVTT pause-on-exit flag

Hmm, there have been some changes recently and pauseOnExit is now a
settable attribute on TextTrackCue:
http://www.whatwg.org/specs/web-apps/current-work/#texttrackcue /
http://www.w3.org/html/wg/drafts/html/master/single-page.html#texttrackcue
, not just read-only as in the spec that you linked.

Also, WebVTTCue inherits from TextTrackCue:
http://dev.w3.org/html5/webvtt/#webvtt-api . So, pauseOnExit can be
set by JavaScript, which will satisfy all Web-based application logic
requirements (such as: pause video at end of cue to show an ad, or to
show a different relevant resource, or to finish synthesizing speech
of a kind=descriptions text track).

So, your question is about also making it possible to provide it
declaratively in a WebVTT file. This comes down to whether there is a
need for content publishers to control the flow of the video playback
with the text tracks they supply.  Or asked differently: is there any
use where the display of the supplementary content at the end of a cue
that is paused is not controlled by JavaScript or the browser, but
needs to be in the hands of the text track author.

If you can think of some, do share.

Cheers,
Silvia.



On Thu, Apr 25, 2013 at 7:02 AM, Joshua Dwire <joshua@sometechie.com> wrote:
> That's a good question.
>
> I've wondered how the pauseOnExit flag made it into the TextTrack Working
> Draft, but I can foresee some possibilities.
>
> One use case would be a tutorial or educational video that has captions
> explaining what is being done and then automatically pauses to let the
> viewer repeat the process. I'm sure there are others.
>
> The main reason reason I think this should be implemented is that it would
> maintain consistency with the rest of the specs - all of the other
> TextTrackCue properties can be set from the WebVTT file, why not
> pauseOnExit? It's in the TextTrack Working Draft at
> http://www.w3.org/TR/2011/WD-html5-author-20110705/the-track-element.html#text-track-cue-pause-on-exit-flag.
> If the user agent already supports the TextTrackCue pauseOnExit flag and
> supports other WebVTT cue settings, it wouldn't take much more work to
> support reading the pauseOnExit flag from the WebVTT file.
>
> Any other thoughts on this?
>
> --
> Joshua Dwire
> Chief Technologist
> Some Techie, LLC
> joshua@sometechie.com
>
> On Apr 24, 2013, at 4:38 PM, Simon Pieters <simonp@opera.com> wrote:
>
> On Wed, 24 Apr 2013 14:30:10 +0200, Joshua Dwire <joshua@sometechie.com>
> wrote:
>
> Quick introduction (hope this doesn't seem like an ad): I'm the owner of
> Some Techie, LLC. We're working on a JavaScript media player library to play
> audio/video in web browsers using HTML5, Flash, etc.
> (sometechie.com/mediaplayer). We're currently working on implementing
> cross-browser captioning support, based off of Captionator.
>
>
> While working on supporting the TextTrackCue pause-on-exit property, I
> noticed that the current WebVTT Draft Report at
> http://dev.w3.org/html5/webvtt/#dfn-webvtt-cue-settings doesn't support
> setting the pause-on-exit flag in the WebVTT file. Are there any reasons for
> not supporting this?
>
> To support this, I propose that we add the something similar to the
> following text to sub step 2-4 of Parse the WebVTT settings:
>
> If name is a case-sensitive match for "pause-on-exit"
> If value is a case-sensitive match for the string "true", then let cue's
> text track cue line pause-on-exit flag be true.
> Otherwise, jump to the step labeled next setting.
>
> We would also need add something similar to the following text to the WebVTT
> cue settings section, consistent with the way boolean HTML attributes are
> interpreted:
> A WebVTT pause-on-exit cue setting consists of the following components, in
> the order given:
>
> The string "pause-on-exit".
> A U+003A COLON character (:).
> The string "true".
> NOTE
>
> A WebVTT pause-on-exit cue setting configures whether playback of the media
> resource is to pause when the cue stops being relevant.
>
> Is there any reason that something like this is not currently in the draft
> report?
>
>
> What's the use case?
>
> Thanks for all of your work on the WebVTT Draft Report. It's been very
> helpful.
>
> --
> Joshua Dwire
> Chief Technologist
> Some Techie, LLC
> joshua@sometechie.com
>
>
>
> --
> Simon Pieters
> Opera Software
>
>

Received on Monday, 13 May 2013 08:00:49 UTC