Re: [MMUSIC] RTSP: New Range header construct

[Sean Sheedy <Sean.Sheedy at arrisi.com>]

On Mon, 2008-11-24 at 04:55 -0800, HAAS Christian wrote:
> From: Sean Sheedy
> > I've (finally) added a new construct for Range that allows simple skip
> > behavior (e.g., skipping 30 seconds over a commercial).  I proposed this
> > late last year, and it was met with resounding silence, which I take as
> > consent:
> > [...]
> 
> I don't see the reason to avoid one extra round trip for this probably rarely
> used feature. I'd rather go into the direction of a fast-forward (Scale
> header) to have more usage options if the clients are annoyed to query the
> server and perform a jump.

I already have a customer who uses repeated skips in place of visual
fast forward or rewind.  With the current RTSP semantics, it requires
two round trips for each skip.  For their use case, saving the extra
round trip is significant.  (BTW, supporting this customer was the
initial impetus for the proposal.)

> Although I don't have that much problems with a list of ranges in one header
> as it is now, I might get them when these relative positions are allowed as
> well; The following, valid, header would give me some headaches:
> 
> Range: current+10-current+20, current-5-, current-30-current-20
> 
> Do all these 'current's refer to the position at the time of arrival of this
> message, or are they to be resolved whenever one range entry is completed?
> (The latter case is the one giving me headaches, because the I'd have to
> handle yet another case next to 'now', 'start/end', 'abs-pos')

"current" is intended to be the current play location at the time of the
arrival of the message.  I should clarify this in the draft.

> I know, this example does not make that much sense, but from the point of
> implementation, I need to know what to do if someone found some
> application...

Shaking out weird corner cases early is always good.

Regards,
Sean

~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--
Sean Sheedy
Staff System Software Engineer, Media and Communications Systems
Sean.Sheedy at arrisi.com | 503-531-6427 (Phone)
~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--




_______________________________________________
mmusic mailing list
mmusic at ietf.org
https://www.ietf.org/mailman/listinfo/mmusic