- From: Jim Helman <jim@nc.com>
- Date: Mon, 03 May 1999 21:36:08 -0700
- To: www-tv@w3.org
- cc: gomer@lgerca.com, fin@finseth.com
On Fri, 26 Mar 1999 (CST) "Craig A. Finseth" wrote: > In my view this is exactly the sort of application for which the "tv:" > URI scheme is suited. If I understand you correctly, the application is > running on a web server at the cable head end (or closely associated > with the cable head end). It knows everything about the channels on the > receiver where the client is running. Thus, a reference to a channel > number is unambiguous. > > YES, BUT ONLY IF THE BOX HAS NO OTHER INPUTS! > > We were not willing to design to this restriction. > > Hence, it is not acceptable for a cable system to use "tv:#" and > expect it to be unambiguous. Actually, I believe that multiple inputs is a strong argument for the necessity of a scheme that allows more direct control. Indeed, tuner and channel numbers have no place in content that is intended to play universally, and so probably have no place in the btv spec. In public content, which may be broadcast, saved, emailed, etc., a resource like a channel should be named by its universal name. Such content should not use locale- or platform-centric identifiers such as a particular channel number or tuner id. The client implementation should be able to choose the best way to deliver the the specified resource. No argument there. For example, on a TV with two tuners, one for PIP and one full- screen, the implementation, not the content, should select which tuner to use based on the size of the image in the HTML page. The mechanism (which tuner) should never be specified by generic content. And so should not be part of the btv URL scheme. But there are user-interface applications (e.g. TV UI, EGP, etc.) on the client or within a local system which do need to be able to specify details such as tuner and channel number. For example, a UI app that goes through all the autoscanned channels on the first tuner and then on the second one might need to display tv:69?tuner=first followed by tv:2?tuner=second. Just as a scheme for file: is essential to many browser usages on a computer, this type of physical specification is required by UI applications on many TV systems. So, from necessity, names will emerge. The only question is whether the naming will be standardized or chaotic. I think a formalized naming scheme would be very beneficial. Structured namespaces for physical TV channels already exist (e.g. NTSC, PAL, ATSC, etc.); so there is a sound basis on which to build a structured, uniform naming scheme (certainly more uniform that file:!). Please let me know your thoughts. regards, -jim Jim Helman Network Computer, Inc. jim@nc.com 650.631.4638
Received on Tuesday, 4 May 1999 00:37:11 UTC