- From: Dan Zigmond <djz@corp.webtv.net>
- Date: Wed, 6 Jan 1999 12:44:40 -0800
- To: "'Gomer Thomas'" <gomer@lgerca.com>, WWW TV List <www-tv@w3.org>
At the risk of degenerating into a purely philosophical debate, I'm not sure I agree that the "tv:" URL doesn't describe an "image." The television broadcast is an image of sorts, and certain behaves like an image in terms of page layout. (In other words, you can put it anywhere on an HTML page where you can put an image, and image attributes around position and size make perfect sense for television broadcasts.) One of the big advantages of using a URI for TV broadcasts was that it can then integrate so well with the rest of HTML. For example, the OBJECT tag provides a nice way of authoring content that can either include a TV broadcast or not, depending on the client: <OBJECT src="tv:"> <OBJECT src="http://foo.com/still_image.png"> </OBJECT> </OBJECT> It also provides a natural URI for "pure TV"; when you want to get rid of all enhanced content and go back a full-screen television image, you simply go to the "page" described by "tv:" itself. At the very least, a television broadcast seems just like any other video. So a <TV> tag makes sense only if you also imagine a <VIDEO> tag. If you believe ordinary video clips should be embedded in HTML using the OBJECT tag with URIs pointing to the source of the video, then using this technique for television as well seems to make sense. Dan --------------------------------------------------- Dan Zigmond Senior Manager, Interactive Television Technology WebTV Networks, Inc. djz@corp.webtv.net --------------------------------------------------- -----Original Message----- From: Gomer Thomas [mailto:gomer@lgerca.com] Sent: Wednesday, January 06, 1999 12:22 PM To: WWW TV List Subject: Re: one more requirement Mike - To add these to the application scenario list we need enough detail to understand the application scenarios. How are these URIs used? Where do they come from? How is the application supposed to treat them? My understanding is that they typically appear in HTML pages. I think one example given in the WebTV internet draft is <img src=tv:>. Presumably the HTML engine rendering the HTML page is supposed to play the currently tuned channel in the space defined by the other parameters of the img tag, or use some default size if no size parameters are specified? Where would the HTML page typically come from in this scenario? A web site? VBI line 21 of an NTSC broadcast channel? I.e., what is the context within which a designation such as "7" or "abc" should be interpreted? I do not believe that we need to proserve legacy syntax, but I do believe that we need to ensure that the application requirements met by that syntax is met in some way within our framework. For example, my own personal view is that the syntax <img src=tv:> is unfortunate. It says to put in an image space something which is not an image in the usual sense, and it uses the syntax of a URI for something which is not identifying anything. If I had been part of the original design team, I would have recommended syntax more like the following for your three examples: * <tv> * <tv chan=7> or possibly <tv src=ntsc://7> * <tv network=abc> or possibly <tv src=ntsc://abc> and for the other example sometimes given in this context: * <tv station=wnyc> or possibly <tv src=ntsc:wnyc> (but how to distinguish network from station?) This proposed "tv" tag could of course have other appropriate attributes for specifying size, volume level, closed captioning, etc., or perhaps parameters like volume level and closed captioning could be specified by queries at the end of the URI. Michael A. Dolan wrote: I think we should add to the application scenario list (or requirements, whichever is more appropriate) the existing commercial practice for "tv" URI's in existing (NTSC) broadcast systems. This list may not be complete, but the ones I know about are: tv: [reference to the currently tuned channel] tv:<channel_number> tv:7 tv:<network_name> tv:abc This syntax obviously presumes a specific transport and is very limited in scope, but one could envision a more complex scheme where this syntax falls out as valid *relative* URI's. In any event, I think this syntax should be addressed and accommodated if possible as we move forward with our designs. Mike --------------------------------------------------------------------------- Michael A. Dolan, Representing DIRECTV, (619)445-9070 FAX: (619)445-6122 PO Box 1673 Alpine, CA 91903, Overnight: 20239 Japatul Rd, Alpine, CA 91901 -- Gomer Thomas LGERCA, Inc. 40 Washington Road Princeton Junction, NJ 08550 phone: 609-716-3513 fax: 609-716-3503
Received on Wednesday, 6 January 1999 15:44:45 UTC