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Subject: Re: [emergency] Groups - Draft Meeting Notes 8-19-2005.doc uploaded

I'm disappointed to see that we are essentially allowing enormous video
chunks to be inserted into the EDXL payload (if I understand the minutes

For streaming video, the bitrate should be included instead of the size,
this way a parser can determine if it is on a high enough bandwidth link
to access the streaming video.

3 relevant variables to streaming video which should be in the DE are:

1. What format is it and how to access it (an SDP file usually describes
this) i.e. what method of access (video codecs, etc.) does it use (HTTP,
Multicast, UDP, ..). This metadata file should either be included as
derefuri or referenced by uri.
2. The bitrate of the video (in kbits/sec)
3. The availability of the video (times during the day)

(2) and (3) are contained in SDP files but not in many other streaming
metadata descriptor formats. I'd suggest that SDP be used for the
URI/DrerefURI fields whenever streaming video is used:


I'd also like to point out that it is *impossible* for the DE to contain
streaming video. 

The size of the video inside the DE will always be known because it has
to be a finite size when it is base64 encoded. 

If the video is streaming and is recorded to be encoded, the sender can
approximate the size of the video by using the recording time and
bitrates of the system, video, and audio components and offsetting them
by the encoding parameters if the stream if it is variable bitrate.

Inserting the size of the video chunk in the message only helps if the
system transmitting the EDXL data can analyze each message and
inform/split messages before transmission to recipients. Essentially
anyone who cannot handle the message has to create an intelligent
gateway because the messages cannot be routed.

I am curious to know what type of network David's video sits on and what
the rationale is for including it in the payload vs. moving it across
the network by other means.


On Sat, 2005-08-20 at 09:00 +0000, ejones@warningsystems.com wrote:
> Please review the draft meeting notes for the 8/19/05 telecon.  Any
> corrections should be emailed to Julia and copied to Elysa as soon as
> possible or be prepared with comments for the 8/23/05 meeting. 

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