Subject: Re: (Q) mbone media on demand service

From: "Alan J. Flavell" <[email-masked]>
Date: Tue, 17 Dec 1996 19:53:30 +0000

> I'm planning to build a mbone archive site.
> And I'd like to have a sample site. Is anyone operating a mbone
> media on demand service?

I operated one in Summer 1994 for a specific purpose (ICHEP94 conference)
and continued to run it for a couple of years after.  It was based on
versions of nv_play and vat_play (Klemets) and some perl scripts
(V.Kumar).  However, these tools are now considered obsolete and the
server in question had been abandoned. 

The more recent "mbonevcr" tool looks to be a very useful facility, and
I've used it hands-on for recording and replaying MBone sessions, but is
not suitable in its original form to be remote-controlled by a distant
user. From the release notes it appeared that the author was aware of a
requirement for a version that could be used as a media-on-demand server
over the net, but I haven't heard anything about developments in that
direction.

I delayed responding to this mail, in case anyone else had some
information on that, but as I've seen no responses, I thought I would 
send this brief response myself.

---

From: Jeff Smith <[email-masked]>
Date: Tue, 17 Dec 1996 13:51:15 -0800

Some work is being done at UCL by Peter Kirstein
([email-masked]) and we, at NTT, are working on a media
server as part of a larger project (http://ecolabor.nttlabs.com)

js

 |>
 |>
 |>> I'm planning to build a mbone archive site.
 |>> And I'd like to have a sample site. Is anyone operating a mbone
 |>> media on demand service?
 |>
 |>I operated one in Summer 1994 for a specific purpose (ICHEP94 conference)
 |>and continued to run it for a couple of years after.  It was based on
 |>versions of nv_play and vat_play (Klemets) and some perl scripts
 |>(V.Kumar).  However, these tools are now considered obsolete and the
 |>server in question had been abandoned. 
 |>
 |>The more recent "mbonevcr" tool looks to be a very useful facility, and
 |>I've used it hands-on for recording and replaying MBone sessions, but is
 |>not suitable in its original form to be remote-controlled by a distant
 |>user. From the release notes it appeared that the author was aware of a
 |>requirement for a version that could be used as a media-on-demand server
 |>over the net, but I haven't heard anything about developments in that
 |>direction.
 |>
 |>I delayed responding to this mail, in case anyone else had some
 |>information on that, but as I've seen no responses, I thought I would 
 |>send this brief response myself. 
 |>
 |>

---

From: Larry Rowe <[email-masked]>
Date: Tue, 17 Dec 1996 18:06:46 -0800

Hi -

We are working on an RTP capture and on-demand replay mechanism that will 
support full-function VCR controls (i.e., variable speed play forwards and 
backwards and random positioning).  We have the RTP record program working, a 
couple of small bugs left to find when the recording tool records a long 
session, and we are working on the media server and client VCR controls now.  
The idea is to play the on-demand into a regular RTP stream that can be viewed 
with any Mbone viewer but couple it with VCR controls accessed through a web 
page.  We'll probably also do a plug-in ourselves for viewing the on-demand 
streams.

The RTP record tool creates a Continuous Media Toolkit (bmrc.berkeley.edu/cmt) 
clipfile that contains all RTP packets with timing synchronized to one logical 
time system (LTS) using the source time in each packet.  The recorder stores 
all streams in a session.  We also have a stream for storing GIF files and 
synchronizing images and Tcl commands to the playback LTS so that we can do 
slides synchronized with the audio and video.

We are watching the RTSP, RTSP', and other control protocol discussions to see 
if there is anything we can use.

I hope to have the recording tool and playback tools working well enough in 
the early part of next year to use them to record the Berkeley Multimedia 
Seminar series this spring (see bmrc.berkeley.edu/298 for the list of speakers 
for the spring -- right now it is empty, anyone want to volunteer to give a 
talk?).

As with all software we develop, the source code will be freely distributed on 
the Internet, but don't look for it before the middle of the year.
	Larry Rowe
-- 
Professor Lawrence A. Rowe               Internet:  [email-masked]
Computer Science Division - EECS         Phone: 510-642-5117
University of California, Berkeley       Fax: 510-642-5615
Berkeley, CA 94720-1776
URL: http://www.bmrc.berkeley.edu/~larry