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RE: Action-4: Consolidated Technical Requirement

From: Chris Needham <chris.needham@bbc.co.uk>
Date: Fri, 29 Aug 2014 14:48:33 +0000
To: Shelly Lin <slin@mozilla.com>, Gene Lian <clian@mozilla.com>
CC: BIN HU <bh526r@att.com>, "public-tvapi@w3.org" <public-tvapi@w3.org>
Message-ID: <590FCC451AE69B47BFB798A89474BB3626E04F15@BGB01XUD1006.national.core.bbc.co.uk>
Hi Shelly,

Responding to your comments, and Gene's previous email:

Regarding the Time Shifting requirements, this is essentially pause and resume of live streams, with the ability to reset playback to the latest/live stream position, so likely already covered by <video> element capabilities.

Regarding the Accessibility requirements, I think we can combine these with the Triggered Interactive Overlay Requirements requirements as you suggest, so:

- Under "The following triggers SHALL be supported as long as those triggers are available either in-band or out-band" add "Triggers based on subtitle captions"
- Add "supplementary audio streams (audio description)" to the last item.

I'm happy to update the requirements in the wiki if you think these changes are OK.

It's possible that these requirements are covered by the existing APIs for multiple media tracks. I think in general we should use the existing APIs where we can and not introduce new ones.

With best regards,

Chris

________________________________________
From: Shelly Lin [slin@mozilla.com]
Sent: 29 August 2014 09:10
To: Gene Lian
Cc: Chris Needham; BIN HU; public-tvapi@w3.org
Subject: Re: Action-4: Consolidated Technical Requirement

Hi Bin,

I'm not sure if we have discussed about the topic of multi-tracks media elements, but the wiki page of Technical Requirements[1] remains unchanged so I'd like to call it out again.

Echoing the second proposal from Gene:
The last item in paragraph "Triggered Interactive Overlay Requirements", "The API SHALL be able to provide the webapps with the content of multiple video/audio tracks in the same media stream of a given channel, ...." ,and every items in paragraph "Accessibility Requirements". Combining with paragraph "Integration with HTML <video> and <audio> Elements", shouldn't those use cases covered by the APIs of media resources with multiple media tracks[2]? That is, media elements already have the ability of handling multi-tracks, including in-band media tracks, or external files for text tracks.

I'm just wondering what's the concerns of creating new APIs while there are existed APIs that probably got them covered, and thanks for your time!

[1] https://www.w3.org/community/tvapi/wiki/Main_Page/Technical_Requirement
[2] http://www.w3.org/TR/html5/embedded-content-0.html#media-resources-with-multiple-media-tracks

Best,
Shelly

________________________________
From: "Gene Lian" <clian@mozilla.com>
To: "Chris Needham" <chris.needham@bbc.co.uk>
Cc: "BIN HU" <bh526r@att.com>, public-tvapi@w3.org
Sent: Tuesday, July 8, 2014 5:24:17 PM
Subject: Re: Action-4: Consolidated Technical Requirement

Hi Chris,

I'd like to have two comments below:

1. Time Shifting Requirements [1]

   I think it's a matter of utilizing the recorded programs. Right?
   I mean it's just a UI issue on the app level to resume the recorded
   program which can start to be recorded when the user pauses it. If
   our APIs can support recording, the app can do whatever it wants to
   time-shiftly playback the recorded program, so I don't think we
   need new API requirements for this case. Or we can just move it into
   the Program Recording Requirements section.

2. Accessibility Requirements [2]

  I think part of the items here have been mentioned by the section
  Triggered Interactive Overlay Requirements [3]:

  "The API SHALL be able to provide the webapps with the content of
   multiple video/audio tracks in the same media stream of a given
   channel..."

  where the subtitle can just be a *text track* in the media stream?

  I understand you want to emphasize the capabilities of enabling or
  disabling the tracks (no matter it's an audio, video or text track).
  Maybe we can group them into a specific section for the general
  manipulation on the media stream.


Please correct/educate me if I'm wrong. Thank you! :)

[1] https://www.w3.org/community/tvapi/wiki/Main_Page/Technical_Requirement#Time_Shifting_Requirements
[2] https://www.w3.org/community/tvapi/wiki/Main_Page/Technical_Requirement#Accessibility_Requirements
[3] https://www.w3.org/community/tvapi/wiki/Main_Page/Technical_Requirement#Triggered_Interactive_Overlay_Requirements

Cheers,
Gene

----- Original Message -----
> From: "Chris Needham" <chris.needham@bbc.co.uk>
> To: "BIN HU" <bh526r@att.com>
> Cc: public-tvapi@w3.org
> Sent: Tuesday, July 8, 2014 12:19:03 AM
> Subject: RE: Action-4: Consolidated Technical Requirement
>
> Hi Bin,
>
> Thanks for your work on the requirements. I have added a few more items to
> the Use Cases and Requirements pages: playback of recorded programmes,
> timeshifted playback, and webapp access to broadcast subtitle data.
>
> Best regards,
>
> Chris
>
> ________________________________________
> From: HU, BIN [bh526r@att.com]
> Sent: 07 July 2014 15:20
> To: Gene Lian
> Cc: public-tvapi@w3.org
> Subject: RE: Action-4: Consolidated Technical Requirement
>
> Gene,
>
> It looks great and talk to you tomorrow.
> Bin
>
> -----Original Message-----
> From: Gene Lian [mailto:clian@mozilla.com]
> Sent: Monday, July 07, 2014 3:05 AM
> To: HU, BIN
> Cc: public-tvapi@w3.org
> Subject: Re: Action-4: Consolidated Technical Requirement
>
> Hi Bin,
>
> Thank you very much for consolidating the user cases, which must take
> you lots of time and efforts. This work is awesome!
>
> Btw, I also follow your changes and semantic to add a new item for the
> Conditional Access System (CAS) Requirements [1].
>
> Meet you guys soon! :)
>
> [1]
> https://www.w3.org/community/tvapi/wiki/Main_Page/Technical_Requirement#Conditional_Access_System_.28CAS.29_Requirements
>
> Regard,
> Gene
>
> ----- Original Message -----
> > From: "BIN HU" <bh526r@att.com>
> > To: public-tvapi@w3.org
> > Sent: Tuesday, July 1, 2014 10:19:13 PM
> > Subject: Action-4: Consolidated Technical Requirement
> >
> > Hello team,
> >
> > I have an open action item to consolidate input contributions of technical
> > use cases to technical requirements. Here you are [1].
> >
> > Basically, what I did are:
> >
> > (1)    Categorized them into 11 functional groups according to original
> > input
> >
> > (2)    Re-worded the requirements with more normalized language, e.g.
> > "SHALL
> > be" instead of "is", wherever appropriate
> >
> > (3)    Re-worded the requirements to focus on API's v.s. the webapps
> > development instead of app function / user interaction
> >
> > (4)    A few duplicates from different inputs were consolidated
> >
> > (5)    A few webapps requirement (e.g. app functions or UI functions) were
> > not captured because those are not directly related to APIs
> >
> > Regarding (4) above, here are highlighted specifics:
> >
> > -          "The API is able to let the user scan (or stop scanning) the
> > channels that are available on the air" (Mozilla, Channel) is duplicate and
> > consolidated into "Tuner Channel Scan Requirements" category
> >
> > -          The ETRI / Program requirements were consolidated into "General
> > Program Requirements"
> >
> > -          The ETRI / Source requirements were consolidated into "General
> > Channel Requirements"
> >
> > -          Re "The API is able to let the user retrieve data from the
> > broadcaster's remote servers to provide more program-/content-related
> > information. To do this, we need to define a universal way to identify the
> > program on the web" (Mozilla, Others), essential functional requirements
> > were consolidated into "General Program Requirements", while app functions
> > were not captured.
> >
> > Regarding to (5) above, here are highlighted specifics:
> >
> > -          "The API is able to let the user watch multiple programs
> > concurrently on the screen (e.g., Picture-in-Picture)" (Mozilla, Others)
> > seems an application function (UI related), thus it was not captured.
> >
> > -          "The API is able to let the user navigate through the EPG and
> > directly select a program to watch" (Mozilla, EPG) seems an application
> > function (UI related), thus it was not captured.
> >
> > -          "The API is able to let the user browse through the list of
> > other
> > programs while (s)he is watching a program" (Mozilla, EPG) seems an
> > application function (UI related), thus it was not captured.
> >
> > -          The ETRI / Channel requirements seems an application function
> > (UI
> > related), thus it was not captured.
> >
> > -          Note: If certain API functions are indeed needed for any of
> > above,
> > e.g. events and/or triggers, we can add it.
> >
> > Let me know if there is any question, and we can discuss it in the mailing
> > list and the conference call next Tuesday.
> > Thank you
> >
> > Bin
> > [1] https://www.w3.org/community/tvapi/wiki/Main_Page/Technical_Requirement
> >
>
>
>
Received on Friday, 29 August 2014 14:54:25 UTC

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