- From: Steve Morris via GitHub <sysbot+gh@w3.org>
- Date: Fri, 27 Jan 2017 15:18:23 +0000
- To: public-tvcontrol@w3.org
I understand Igarashi-san's point, and there are differences between the models used for retail TVs and for subsidized STBs. My view on the issue of constraints is that constraints should work across all sources. The case where a device may only be able to support a certain number of concurrent streams, or may have limited ability to support multiple source types at the same time, for whatever reason, is one that needs to be supported. There will be differences between platforms that mean these capabilities and constraints will be different, but I think that the constraints mechanism is flexible enough to deal with this. For me, the problem with having the channel lists on the sources is this: if the device UI manages the channel list, and has an option to show the user a merged channel list, an app can't create a merged channel list that matches the one the device UI will show (because the user may have re-ordered the channel list in the device UI, for instance). Unless there is an API for getting the channel list on the TVManager object, I don't see a way to solve this. I see a couple of possible solutions for dealing with the case where sources can't be handled seamlessly - whether for technical or business reasons. One option is to simply say that when the user selects which source they want, this is done *outside* the scope of the TV control API. An app will then see only those sources which the user has currently selected: for instance, if the user has selected the DVB-S source, then in the set of capabilities an app will only see DVB-S as a supported source type. Similarly, when the app calls TVManager.getChannelList(), it only gets a list of the channels available over DVB-S. The second approach is for TVManager.getChannelList() to take a set of constraints as a parameter, where those constraints specify which source (or set of sources) should be included in the returned channel list. An implementation can then return an appropriate response if the app requests channels from a set of sources that can't be handled seamlessly. Both of these approaches let us solve the problem without needing getChannelList() methods in different places to handle the two use cases: the question then becomes, in the case where sources can;'t be handled seamlessly, does the user agent need to be aware of this, or is that selection outside the scope of the user agent? Steve. -- GitHub Notification of comment by stevem-tw Please view or discuss this issue at https://github.com/w3c/tvcontrol-api/issues/4#issuecomment-275689292 using your GitHub account
Received on Friday, 27 January 2017 15:18:29 UTC