Subject: Re: [MMUSIC] Question about the various "range-spec"s defined for RTSP 2.0 (and RTSP 1.0)

From: Magnus Westerlund <[email-masked]>
Date: Mon, 23 Jan 2012 10:29:43 +0100

On 2011-11-26 20:53, Ross Finlayson wrote:
> In "draft-ietf-mmusic-rfc2326bis-28" (and preceding), a "npt-range-spec"
> is defined as
> npt-range-spec = ( npt-time "-" [ npt-time ] ) / ( "-" npt-time )
> (ditto for "smtp-range-spec" and "utc-range-spec").
> 
> This suggests that the following are valid:
> npt = -now
> npt = -12.34
> 
> What are these supposed to mean (especially given that - in section 4.5
> - you say that "Negative values are not defined")?

It means play from "now" or stored playout point _until_ the given
value. I agree that npt=-now does not make sense, so that should be made
clear is not valid. Please also remember that the timescale can go
backwards.

Cheers

Magnus Westerlund

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