Re: [media] a first draft JavaScript API for multitrack media

On Thu, Feb 18, 2010 at 4:14 AM, Geoff Freed <geoff_freed@wgbh.org> wrote:
> On 2/16/10 10:44 PM, "Silvia Pfeiffer" <silviapfeiffer1@gmail.com> wrote:
>
> Hi all, and in particular media subgroup,
>
> Today we had a phone discussion about the JavaScript API spec and we
> realised that we haven't actually specified the list of roles that the
> @roles attribute should accept.
>
> So, I wanted to start a discussion on this with the goal of eventually
> reaching a list that we can all agree on to cover the known use cases.
>
> Let me start by stating that in today's call everyone agreed that we
> need to come up with a determined list of values for the roles, so if
> you disagree with that, you should speak up now.
>
> So, let me start proposing a list of track roles:
>
> Video track roles:
> * "main"
> * "alternate" (e.g. different camera angle; happy to stick with Apple
> terminology ;-)
> * "sign" (for sign language)
>
> Audio track roles:
> * "main"
> * "alternate" (probably linked to an alternate video track)
> * "dub"
> * "audesc" (audio description)
> GF:  audiodesc (or audioDesc) would be more descriptive
>
> * "music"
> * "sfx" (sound effects)
>
> Text track roles:
> * "caption"
> * "subtitle"
> * "textaudesc" (textual audio descriptions; to be used as braille or
> through TTS)
> GF:  despite its length, textaudiodesc (or textAudioDesc) would be more
> descriptive, I think.
>
> * "karaoke"
> * "chapters"
> * "ticker text"
> * "lyrics"
>
> We could most certainly also think about abbreviating them, e.g. "CC",
> "SUB", "AD", so I wonder what everyone's preferences are here.
>
> GF:  My preference would be for not abbreviating them:  it makes them
> immediately obvious, plus it conforms to other usages of @role
> (http://www.w3.org/TR/wai-aria/roles#role_definitions;
> http://www.w3.org/TR/ttaf1-dfxp/#metadata-attribute-role are two examples).
>
> So, shoot away with your own preferred track types! What conventions
> are you used to from MPEG?
>
> GF:  Speaking of conventions, we should probably settle on a naming
> convention:  camelCase (e.g., role=”tickerText”), all lowercase (e.g.,
> role=”tickertext”) or spaces (e.g., role=”ticker text”).  My preference
> would be for camelCase.
>

All makes sense to me. Having looked at other @role definitions I
think we should conform with their all lowercase markings.

See the list now at
http://www.w3.org/WAI/PF/HTML/wiki/Media_MultitrackAPI#Available_Roles
.

Cheers,
Silvia.

Received on Thursday, 18 February 2010 00:22:34 UTC