Re: How do authors use TV URLs? (was RE: URL: Background and Requirements)
From: Craig A. Finseth (fin@finseth.com)
Date: Thu, Nov 05 1998
Date: Thu, 5 Nov 1998 11:03:03 -0600 (CST)
Message-Id: <199811051703.LAA00625@isis.visi.com>
From: "Craig A. Finseth" <fin@finseth.com>
To: Ted.Wugofski@otmp.com
Cc: www-tv@w3.org
Subject: Re: How do authors use TV URLs? (was RE: URL: Background and Requirements)
Has someone documented "who" will use these URLs. I was under the
impression that URLs would be specified by humans.
In the WWW today, a content author links to a known resource on the
Internet through a URI. Carrying this over to television, this says
that an interactive content author links to a known resource in the
television transport through a URI. Yes, it may also point to the
Internet, but that is well understood.
If this is true, I have a hard time imagining a content developer being
able to specify a URL that references another stream prior to encoding
and multiplexing. None of the addressing information is available when
I originally authored the content.
Bingo!
Even if the addressing information was known a priori, it would be
invalid when the program is rebroadcast at a later time or in a
different transport.
Double bingo!
To get around this, I would have to encode something symbolic (a logical
URL) that gets modified once everything is encoded, the multiplex is
created, and all of the identifiers specified. Then I would need
something that would either map this logical URL to the real resource at
run-time, or transcode the content with the proper URLs (physical URLs).
No, because the URL has to remain non-specific with respect to the
transport.
What am I missing here?
Nothing. The URLs must remain transport-independant.
I can't imagine a usable and reuseable URI scheme (for a television
transport) unless there is a level of indirection. In other words, the
URI points to the table and RDF is used to "find" the particular
transport, stream, and packet.
Or something equivalent.
Craig