- From: Bob Lund <B.Lund@CableLabs.com>
- Date: Fri, 8 Apr 2011 13:25:46 -0600
- To: Matt Hammond <matt.hammond@rd.bbc.co.uk>, Clarke Stevens <C.Stevens@CableLabs.com>, "public-web-and-tv@w3.org" <public-web-and-tv@w3.org>, Olivier Carmona <ocarmona@awox.com>, Russell Berkoff <r.berkoff@sisa.samsung.com>
- CC: Giuseppe Pascale <giuseppep@opera.com>
Hi Matt, So if I understand correctly, you're thinking about a service to control the TV - content never leaves it. This UPnP service http://upnp.org/specs/av/UPnP-av-RenderingControl-v2-Service.pdf provides a remote interface to some controls of a rendering device but probably not all of the controls a TV with a tuner would have. Sometime ago when Web and TV had its first workshop, Doug Schepers solicited input for remote control events related to TV with the intent, I believe, of defining DOM3 events for these. This would enable remotes to work across UI implementations running on compliant user agents. Bob > -----Original Message----- > From: Matt Hammond [mailto:matt.hammond@rd.bbc.co.uk] > Sent: Friday, April 08, 2011 9:59 AM > To: Clarke Stevens; public-web-and-tv@w3.org; Olivier Carmona; Russell > Berkoff; Bob Lund > Cc: Giuseppe Pascale > Subject: Re: [HOME_NETWORK_TF] Home Network Technologies > > Hi Bob, > > Your latter example is what I had in mind: a device that is connected to > the home network and receives off-air broadcasts, but does not serve or > stream that content around the home network. Instead the device itself > includes a display, or is connected directly to one using HDMI or > similar. > > It is not clear to me if the A/V transport service (or whichever service > is appropriate) facilitates remote control type functions such as > changing channel or playing back a recording, as distinct from choosing > content to stream to another device. > > regards > > > > Matt > > On Fri, 08 Apr 2011 15:30:58 +0100, Bob Lund <B.Lund@cablelabs.com> > wrote: > > > Matt, > > > > See inline below. > > > > Bob > > > >> -----Original Message----- > >> From: Matt Hammond [mailto:matt.hammond@rd.bbc.co.uk] > >> Sent: Friday, April 08, 2011 3:03 AM > >> To: Clarke Stevens; public-web-and-tv@w3.org; Olivier Carmona; > >> Russell Berkoff; Bob Lund > >> Cc: Giuseppe Pascale > >> Subject: Re: [HOME_NETWORK_TF] Home Network Technologies > >> > >> We also see facilitating discovery of content on the home network > >> from the browser to be important. There is also the issue of security > >> and privacy - a user should be able to determine what devices, > >> applications and web pages have permission to control another device > >> and discover content. > >> > >> As a broadcaster we deliver to multiple platforms over which we have > >> no direct control (terrestrial, cable and satellite transmission all > >> operated by different companies/consortia). Our interest is closer to > >> the scenario > >> 2(b) that you outline. > >> > >> What is not clear to me is whether the DLNA/UPnP capabilities for > >> discovering and playing content also work for a box that does not > >> have the capability to serve or stream off-air broadcast content on > >> the home network (for example, a TV with integrated tuner). > > > > I am not clear on the question. If you mean a device that is not > > connected to the home network then UPnP does not address that. But, > > such a device would seem to be out of scope of all home network APIs. > > If you mean a device that is connected to the home network but does > > not have the capability to serve or stream off-air broadcast content, > > then yes, the device can host the content discovery, connection > > manager and A/V transport services. A TV with an integrated tuner > > could serve off-air broadcast content if it was also connected to the > > home network and had the appropriate UPnP services. > > > > > >> This is one of the > >> reasons why we have an interest in a simplified abstraction that > >> negates the need for a controlling device to concern itself with the > >> source and delivery method of a piece of content (as well as its > >> format, codecs, device profiles etc) > >> > >> There is also potential to enable a substantial accessibility win > >> here too if UI can be independent of the device(s) it is controlling. > >> > >> When considering the Remote UI as mentioned here, perhaps there are > >> at least 3 related strands to this? Discovery/security; remote > >> control; device-served remote UI. > >> > >> regards > >> > >> > >> > >> Matt > >> > >> On Thu, 07 Apr 2011 20:14:19 +0100, Bob Lund <B.Lund@cablelabs.com> > >> wrote: > >> > >> > To amplify on Clarke's point a bit, it's useful to break down the > >> > broadcast/cloud UI into more specific scenarios: > >> > 1) Broadcast content directly from the cloud, UI from the cloud > >> > 2) Broadcast to a UPnP media server that proxies the content on the > >> > home network via content directory service, remote UI from the > >> > cloud > >> > > >> > Scenario 1 is the web, nothing special needs to be introduced. > >> > Scenario 2 is more of a DLNA/UPnP model. There are two ways the UI > >> > served from the cloud can gain the links to refer to the media > >> > server > >> > content: > >> > a) A back channel from the media server hosting the CDS to the > >> > cloud server constructing the UI page. If the service provider > >> > controls both the media server software implementation and the > >> > cloud UI server this back channel can be service provider specific. > >> > The cloud UI server constructs UI that references the home network > >> > content. There are some subtleties around how the media LAN side IP > >> > address is referenced in the UI page but it's doable. > >> > b) The UI page served by the cloud server to the home network > >> > device contains JavaScript that uses the discovery API that is > >> > being proposed to discover the CDS and the content therein. The UI > >> > page JavaScript can provide whatever degree of integration is > >> > desired between the local content discovered and the cloud content > >> > referenced on the UI > >> page. > >> > > >> > Bob Lund > >> > > >> >> -----Original Message----- > >> >> From: public-web-and-tv-request@w3.org [mailto:public-web-and-tv- > >> >> request@w3.org] On Behalf Of Clarke Stevens > >> >> Sent: Thursday, April 07, 2011 11:05 AM > >> >> To: Matt Hammond; public-web-and-tv@w3.org; Olivier Carmona; > >> >> Russell Berkoff > >> >> Cc: Giuseppe Pascale > >> >> Subject: RE: [HOME_NETWORK_TF] Home Network Technologies > >> >> > >> >> Matt, > >> >> > >> >> UPnP currently defines a way to discover remote user interfaces, > >> >> but it is pretty generic. Here are the specs: > >> >> > >> >> http://upnp.org/specs/rui/remoteui/ > >> >> > >> >> In this group, we're hoping to make this a bit more concrete by > >> >> using HTML browsers, CSS, JavaScript, and providing some APIs for > >> >> discovering and using devices and services on the home network. > >> >> The back channel to the cloud service would just be a URL. That's > >> >> maybe a bit oversimplified as there are other issued related to a > >> >> commercial service offering, but that's the basic idea. > >> >> > >> >> As for more information on DLNA CVP, here's an announcement: > >> >> > >> >> http://www.dlna.org/news/pr/view?item_key=e2c163bfab8076edc2b33eba > >> >> 829 > >> >> 3e8 > >> >> 2cd2f11e3e > >> >> > >> >> It looks like DLNA doesn't yet have CVP for sale from its web site > >> >> but W3C could encourage them to provide some more information, > >> >> timelines, etc. > >> >> > >> >> Hope this helps. > >> >> > >> >> Thanks, > >> >> -Clarke > >> >> > >> >> -----Original Message----- > >> >> From: Matt Hammond [mailto:matt.hammond@rd.bbc.co.uk] > >> >> Sent: Thursday, April 07, 2011 8:11 AM > >> >> To: public-web-and-tv@w3.org; Olivier Carmona; Russell Berkoff; > >> >> Clarke Stevens > >> >> Cc: Giuseppe Pascale > >> >> Subject: Re: [HOME_NETWORK_TF] Home Network Technologies > >> >> > >> >> Hi Clarke, > >> >> > >> >> > >> >> Could you explain how this model where a remote user interface is > >> >> served from the cloud would work for broadcast services? Does it > >> >> require some kind of back channel between the rendering device and > >> the cloud service? > >> >> > >> >> I would also like to understand what services CVP enables. Are the > >> >> guidelines publicly available anywhere? > >> >> > >> >> regards > >> >> > >> >> > >> >> > >> >> Matt > >> >> > >> >> > >> >> On Thu, 07 Apr 2011 13:40:12 +0100, Clarke Stevens > >> >> <C.Stevens@cablelabs.com> wrote: > >> >> > >> >> > I think some of the functionality you want is already defined in > >> >> > DLNA/UPnP and the rest will be very soon. As I mentioned > >> >> > earlier, the URL that points to the content does not need to be > >> >> > on the home > >> >> network. > >> >> > This allows for content that can be offered from service > providers. > >> >> > Similarly, a service provider could serve a remote user > >> >> > interface from the cloud. Features such as volume change and > >> >> > mute are already provided, so a "second screen" could get a user > >> >> > interface from a service provider and point to content remotely > >> >> > served by that service > >> >> provider. > >> >> > > >> >> > > >> >> > There is also a DLNA guideline called CVP specifically designed > >> >> > for content service providers. The first version is available > >> >> > now but is somewhat limited. The second version is in > >> >> > development and I believe it provides the remainder of the > >> >> > services you are looking > >> for. > >> >> > > >> >> > Thanks, > >> >> > -Clarke > >> >> > > >> >> > -----Original Message----- > >> >> > From: public-web-and-tv-request@w3.org > >> >> > [mailto:public-web-and-tv-request@w3.org] On Behalf Of Matt > >> >> > Hammond > >> >> > Sent: Thursday, April 07, 2011 2:52 AM > >> >> > To: public-web-and-tv@w3.org; Olivier Carmona; Russell Berkoff > >> >> > Cc: Giuseppe Pascale > >> >> > Subject: Re: [HOME_NETWORK_TF] Home Network Technologies > >> >> > > >> >> > Hi Russell, > >> >> > > >> >> > Your description matches my understanding of DLNA/UPnP - which > >> >> > is useful confirmation for me - many thanks! > >> >> > > >> >> > I agree that this model works well for streaming between home > >> devices. > >> >> > But it makes the assumption that all content is streamable > >> >> > between home devices. A TV or set-top-box that can receive > >> >> > broadcast or IP delivered TV or radio does not necessarily match > >> >> > this. In order to be able to implement some of the second-screen > >> >> > scenarios presented at the last workshop, I would hope that APIs > >> >> > for home networking are also able to query and control TV > >> >> > functions such as changing channel or retrieving broadcast > programme metadata. > >> >> > > >> >> > This is why I am interested in APIs that can support both in (if > >> >> > possible) a single simple unified way. The approach we took at > >> >> > the BBC with our Universal Control (UC) API is one possible way > >> >> > to achieve > >> >> this. > >> >> > > >> >> > If a TV implementing UC API needed to be able to discover and > >> >> > stream content on other devices in the home then it would almost > >> >> > certainly use DLNA/UPnP or other similar technologies to do > >> >> > this, but the client/controller device does not need to know the > >> >> > difference. From the perspective of a client of the UC API > >> >> > implementing TV, streamed content is discoverable and selectable > >> >> > for playback in the same way as a television channel or > >> >> > programme > >> would be. > >> >> > > >> >> > regards > >> >> > > >> >> > > >> >> > > >> >> > Matt > >> >> > > >> >> > On Thu, 07 Apr 2011 08:39:18 +0100, Russell Berkoff > >> >> > <r.berkoff@sisa.samsung.com> wrote: > >> >> > > >> >> >> Hi Matt, > >> >> >> > >> >> >> > >> >> >> Let me try to answer "frame" your question/observation and > >> >> >> hopefully provide some brief answers: > >> >> >> > >> >> >> > >> >> >> Q1: Does DLNA/UPnP distinguish between the description of > >> >> >> content, > >> >> i.e. > >> >> >> metadata describing content (title, description, available > >> >> >> media > >> >> >> formats) and the device actually supplying the content? > >> >> >> > >> >> >> > >> >> >> Q2: Does DLNA/UPnP allow metadata and content to reside on > >> >> >> separate devices on the home network? > >> >> >> > >> >> >> > >> >> >> Q3: Does DLNA/UPnP allow the remote commanding of playback > >> devices? > >> >> >> > >> >> >> > >> >> >> > >> >> >> A1: Yes...DLNA/UPnP has a distinct metadata service > >> >> >> (ContentDirectory Service). The metadata provided by this > >> >> >> service can refer to content elsewhere on the home network. > >> >> >> > >> >> >> > >> >> >> A2: Yes > >> >> >> > >> >> >> > >> >> >> A3: Yes...UPnP/DLNA allows remote commanding of playback > devices. > >> >> >> A Digital Media Controller can obtain descriptive content > >> >> >> metadata and tell a playback device to "pull" a piece of > >> >> >> content from a distinct "content source" on the home network. > >> >> >> > >> >> >> > >> >> >> The Digital Media Controller in this scenario would examine the > >> >> >> metadata from both the Playback Device (Digital Media Renderer) > >> >> >> and from the metadata service (Digital Media Server - > >> >> >> ContentDirectory > >> >> >> Service) and insure a media format is chosen that both the > >> >> >> Content Source can provide and the Playback Device can render. > >> >> >> Once a match is found the Digital Media Controller, would > >> >> >> command the Playback device to fetch the content from the > Content Source. > >> >> >> > >> >> >> > >> >> >> Regards, > >> >> >> > >> >> >> Russell Berkoff > >> >> >> > >> >> >> Samsung Electronics > >> >> >> > >> >> >> > >> >> >> > >> >> >> > >> >> >> -----Original Message----- > >> >> >> From: Matt Hammond [mailto:matt.hammond@rd.bbc.co.uk] > >> >> >> Sent: Wednesday, April 06, 2011 5:03 AM > >> >> >> To: public-web-and-tv@w3.org; Olivier Carmona > >> >> >> Cc: Russell Berkoff; Giuseppe Pascale > >> >> >> Subject: Re: [HOME_NETWORK_TF] Home Network Technologies > >> >> >> > >> >> >> > >> >> >> Hi Olivier, > >> >> >> > >> >> >> > >> >> >> On Wed, 06 Apr 2011 12:22:38 +0100, Olivier Carmona > >> >> >> <ocarmona@awox.com> > >> >> >> > >> >> >> wrote: > >> >> >> > >> >> >> > >> >> >>> > >> >> >> > >> >> >>> Hi Matt, > >> >> >> > >> >> >>> > >> >> >> > >> >> >>> DLNA 1.0 is about two-box pull model: on one side you have a > >> >> >>> Digital > >> >> >> > >> >> >>> Media Player (a client in your description) and on the other > >> >> >>> side you > >> >> >> > >> >> >>> have a Digital Media Server (a rendering device in your > >> >> description). > >> >> >> > >> >> >>> DMP discovers and then browses DMS, and can request one of the > >> >> >>> browsed > >> >> >> > >> >> >>> items to be played. The only difference with your model is > >> >> >>> that this the > >> >> >> > >> >> >>> DMP that based on the information exposed by the DMS, decides > >> >> >>> wherever > >> >> >> > >> >> >>> it can play the content. > >> >> >> > >> >> >> > >> >> >> My explanation was not as clear as it should have been - please > >> >> >> accept my > >> >> >> > >> >> >> apologies for that. The client that I described does not > >> >> >> display media and > >> >> >> > >> >> >> does not send or receive media streams. It is the server that > >> >> >> will > >> >> >> > >> >> >> render/display media, and it is up to the server to work out > >> >> >> what media is > >> >> >> > >> >> >> available to it and to arrange to stream (or otherwise obtain) > it. > >> >> >> This > >> >> >> > >> >> >> aspect would be completely opaque to this client. The > >> >> >> server/renderer > >> >> >> > >> >> >> could well use DLNA to discover and stream that content from a > >> >> >> 3rd device, > >> >> >> > >> >> >> but the client would not be aware of this. > >> >> >> > >> >> >> > >> >> >> For me, the attraction of this model is that it is more > >> >> >> abstract that just > >> >> >> > >> >> >> streaming and can easily subsume access to local storage but > >> >> >> also access > >> >> >> > >> >> >> to services such as live television broadcast. A television > >> >> >> programme is > >> >> >> > >> >> >> just another item of content that the server reports it has > >> >> >> available to > >> >> >> > >> >> >> it, and which the client can ask it to display. > >> >> >> > >> >> >> > >> >> >> > >> >> >> > >> >> >> regards > >> >> >> > >> >> >> > >> >> >> > >> >> >> Matt > >> >> >> > >> >> > > >> >> > > >> >> > >> >> > >> >> -- > >> >> | Matt Hammond > >> >> | Research Engineer, BBC R&D, Centre House, London > >> >> | http://www.bbc.co.uk/rd/ > >> > >> > >> -- > >> | Matt Hammond > >> | Research Engineer, BBC R&D, Centre House, London > >> | http://www.bbc.co.uk/rd/ > > > -- > | Matt Hammond > | Research Engineer, BBC R&D, Centre House, London > | http://www.bbc.co.uk/rd/
Received on Friday, 8 April 2011 19:26:52 UTC