Second Screen Presentation TPAC Breakout Session

13 Nov 2013


See also: IRC log


anssik, jcverdie


<scribe> scribe: anssik

<scribe> scribeNick: anssik


[Dominik shows some slides on the screen, material to be shared after the meeting.]

<jcverdie> are the slides available on the CG page or somewhere?

<jcverdie> ooops thx anssik:)

Q: what is the difference in the definition of the "second screen" in this context re Web & TV?

A: in the TV context, TV is the primary, whereas in this proposal the UA is the primary driver

<stakagi> Is chromecast contained in the use case of second screen?

<jcverdie> (rumors in the room from web&tv fellows who tend to disagree with the previous statement)

<olivier> confirmation that a UA could connect to many screens. whether the application would be able to discover/select many targets is uncertain

<jcverdie> scribe: jcverdie

demo of a firefoxOS game projected on a laptop

the mobile phone turns into a cntrol center while the game is displayed on the big screen

(public can see the demonstrator is not a very good driver :p)

@@@: how many lines of codes changed to enable remote display

anssik: not that many, circa 200 lines

Marcus Altman: what is displayed on the second screen?

anssik: it's a navigator window. it's an URL
... the second demo is a picture gallery

(image with small description on mobile, fullscreen image on secondscreen)

anssik: demo of a hacked youtube page. opens a window on second screen and launches youtube player there
... the demo needs a network connection faster than 33.6 Kbps. Not working here


<anssik> is the only visible browser window shared, or is the whole OS screen to be shared?

dominik: we're using the OS facilities @@@

hongbo: for instance we're using Android SDK to control second display

anssik if you want to take over feel free ;)

dominik: we are trying to use a common ground and rely on OS facilities
... for instance most desktop OS show something as soon as you connect, it's fine

doug: if I want to share a part of my screen e.g. a keynote and a comment window
... I'd do this using CSS w/ different styles

<anssik> DougS: I want to share only a part of the screen, not the whole screen, I'd like to use CSS for that

<anssik> Dominik: we've considered that option

dominik: our initial solution uses API so you can author your content

giuseppe: it's two windows, not 2 divs

ddavis: url for the demo ?

dominik: these demo depend on specific versions of chromium and we haven't released the code

Presentation API

visible online webscreens.github.io/presentation-api


dominik: abstracts physical display techs
... a little bit like fullscreen API for nearby tv
... here's the IDL of the API preview

(dominik describes the IDL)

dominik: there's a boolean displayAvailable to tell you have something available
... and an event to be notified when there are some changes

(now a sample code of the two pages code, one for 1st screen, one for second screen)

dominik: you can use post messages to communicate between screens

giuseppe: when the CG was create it seemed that you were not considering the case where there are two user agents running, just one. Now you're saying this case is considered

dominik: i think it's in scope
... we have tried a variation of this API in such a case, new questions come up

giuseppe: there is already this discussion in other groups

<anssik> https://github.com/webscreens/presentation-api/wiki/Second-Screen-Community-Group-Charter

ddavis: the device discovery is done separately

dominik: it uses the OS to do this, it's not part of the spec

ddavis: what about availability?

dominik: in a simple way. it basically replaces windows.open on another screen

anssik: it's automatically the "open new window move it to second screen"

<Zakim> jcverdie, you wanted to ask about capability check of second screen in the IDL

jcverdie: what about capabilities of the second screen?

dominik: we struggle about the requirements (nearby, ...)
... but that could be added

mounir_: you can't really now where is the second screen. @@@ (missed the end of the question)

dominik: our goal is a simple API

anssik: we should discuss this in the context of SysApps WG

mounir_: this is not something very sensitive except fingerprinting [...]

anssik: our priority is to make it available

+1 nigel

richt: are you planning to specify how it works (discovery, connectivity), sounds like black magic so far

dominik: in our idea, that would be an extension to the OS and from the browser it would just be a secondary display
... community group
... mozilla expressed interest and joined

<ddavis> richt: UPnP is encumbered - there could be patent issues if you're thinking of the user agent incorporating this.

dominik: we're done part of implementation but we're eager to get more information and use cases
... slides will be made available from the session wiki page

<olivier> session wiki page -> http://www.w3.org/wiki/TPAC2013/session-second-screen-web

dominik: thanks attendance

philipp h: have you got a timeframe to move to a WG?

anssik: when there's enough momentum. when we have a better idea of what work we have to do, and we get enough support

richt: which WG?

anssik: any group with good participation

dino: what is a "good level of support"?

anssik: we need interoperable implementations for instance

@@@: are you assuming a single second screen?

anssik: right now it's a simplified API
... but it's possible to perform the same API twice and eventually get a second second screen (pun intended)

jcverdie: i am concerned by the fact you say now you are considering the case of two UA, while you said in the mailing list initially you didn't
... you need to clarify which goal you are pursuing, I am afraid of potential overlap

dominik: i agree we need to clarify

giuseppe: may be it is worth exploring, but you need to clarify

jcverdie: to be clear, i'm just asking for clarification, i'm not saying i'm against it

dino: sometimes your second screen has more power and it makes sense it opens a UA
... also you need to poll for new displays, detect if some new display goes online or offline, if there's delay in the display on 2nd screen, ...

dominik: we'll need additional events yes

dino: likely a big use case will be to display a video

<israelh> q

dino: may be just ask for a specific object to go to the second screen

giuseppe: it would be like a "requestSecondScreen" similar to request Fullscreen

israelh: what about the UI of the user agent (such as geolocation popup, ...)
... where would the question go?

dominik: at this point we don't expect any interaction on the second screen, everything would need to be covered on 1st screen but no use case so far

Summary of Action Items

[End of minutes]

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$Date: 2013-11-13 08:14:11 $

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WARNING: No "Present: ... " found!
Possibly Present: ChristianFuhrhop DougS Kiyoshi Takahiro Tomoyuki Yudong aizu anssik ddavis dino dominik doug drott giuseppe giuseppep gmandyam gwm hisa hongbo https israelh jcverdie joined left mounir_ nigel olivier razybon_ richt sangwhan scribeNick shan stakagi trackbot webscreens wonsuk youenn_ ywu
You can indicate people for the Present list like this:
        <dbooth> Present: dbooth jonathan mary
        <dbooth> Present+ amy

Agenda: http://www.w3.org/wiki/TPAC2013/session-second-screen-web
Got date from IRC log name: 13 Nov 2013
Guessing minutes URL: http://www.w3.org/2013/11/13-webscreens-minutes.html
People with action items: 

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