- From: Harald Tveit Alvestrand <Harald@Alvestrand.no>
- Date: Wed, 01 Sep 1999 08:35:08 +0200
- To: "Michael A. Dolan" <miked@tbt.com>, www-tv@w3.org (WWW TV List)
At 16:58 31.08.99 -0700, Michael A. Dolan wrote:
> >>Program Stream - as defined in ISO 13818-1 for MPEG - a streaming
> >>version of a Program.
> >>
> >>Transport (Stream) - as defined by ISO 13818-1 for MPEG - a
> >>multiplexed collection of concatenated Program Streams without
> >>beginning or end.
>
> >>Channel - a Program Stream. This is also known in DVB as a
> >>"service".
> >
> >Now I'm confused; I would have thought that a Channel would be a
>Transport
> >Stream.
>
>A channel is one Program Stream (analogous to analog TV now - you get
>some video, audio and maybe data). A Transport contains one or more
>Program Streams multiplexed together. This is like the cable
>company, or a digital (DVB or ATSC) system.
I've included only the relevant portions above.
I think the Program Stream definition must be wrong, since a Channel does
not consist of only a single Program, while a Program Stream consists of "a
streaming version of *a* Program".
If we make the definition of Program Stream read "a concatenated collection
of one or more Programs (in streaming versions), which has a beginning,
but may or may not have a definite end", it fits.
Harald
--
Harald Tveit Alvestrand, Maxware, Norway
Harald.Alvestrand@maxware.no
Received on Wednesday, 1 September 1999 02:53:49 UTC