Subject: [clue] Spencer Dawkins' Yes on draft-ietf-clue-framework-24: (with COMMENT)

From: "Spencer Dawkins" <[email-masked]>
Date: Wed, 16 Dec 2015 10:58:46 -0800

Spencer Dawkins has entered the following ballot position for
draft-ietf-clue-framework-24: Yes

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COMMENT:
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I remember the first couple of years of CLUE. This was worth writing.

I'm a Yes, but did have some editorial suggestions and questions.

In Section 1. Introduction,

   Current telepresence systems, though based on open standards such
   as RTP [RFC3550] and SIP [RFC3261], cannot easily interoperate with
   each other.  

this text hasn't changed since the 00 individual draft from 2012. Is it
still true for "current" telepresence systems?
   
In this text:

   If the physical space does not
   have a well-defined front and back, the provider chooses any
   direction for X and Y consistent with right-handed coordinates.
   
is there any reference/pointer you could provide to a definition of
"consistent with right-handed coordinates"? If everyone understands that
but me, please ignore this comment ...

Is "line of capture" a meaningful concept on its own? Or is it only
meaningful as "point on line of capture"?

I wonder if it would be less confusing if you always called "volume of
capture" "3-D volume of capture". I was consistently assuming "volume"
was an audio thing, when I saw "volume of capture" with no qualifier. You
define it as "3 dimentional volume of capture", but then drop that
qualifier in subsequent use.

Is Person Type just a string for presentation? If so, that's fine, but
the framework defines 8 types in some detail, and notes that this list
isn't exhaustive and that custom person types can be defined, so I wonder
if there's any expectation that CLUE will do anything specific, based on
Person Type.

PIP isn't expanded until its 5th use (if I'm reading correctly). I'm
guessing that PiPs is the plural of PiP, but that's a guess, and I
wouldn't mind a word or two of explanation about that. "Tiled" is
probably a term of art, so maybe it doesn't need an explanation, but it's
not clear whether "tiled" and "PiP" are the same thing or not (which
would be a good thing to include in an explanation, if you add one).

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From: Christian Groves <[email-masked]>
Date: Fri, 18 Dec 2015 14:05:37 +1100

Hello Spencer,

Please see my responses below.

Regards, Christian

> https://datatracker.ietf.org/doc/draft-ietf-clue-framework/
[CNG] "line of capture" is a synonym for "the direction and axis of the 
capturing device". Its meaningful. The "point on line of capture" allows 
it to be calculated.
> if there's any expectation that CLUE will do anything specific, based on
[CNG] The string could be presented or it could be consumed for capture 
selection. I.e. the policy of a consumer could say they always want to 
see/hear the "chair". The endpoint would then select captures attributed 
to the chair.
> _______________________________________________
> clue mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/clue
>

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From: "Duckworth, Mark" <[email-masked]>
Date: Tue, 22 Dec 2015 15:35:27 -0800

Hello Spencer,
Thanks for the suggestions. I have some responses below.
Mark

> -----Original Message-----
> From: Spencer Dawkins [mailto:[email-masked]]
> Sent: Wednesday, December 16, 2015 1:59 PM
[Duckworth, Mark] Yes.

> but me, please ignore this comment ...
[Duckworth, Mark] I think Z should be included, so "... any direction for X and Y and Z consistent with right-handed coordinates." I think right-handed coordinates is a well-known thing.

> qualifier in subsequent use.
[Duckworth, Mark] It is mentioned only within a single paragraph, so it seems clear to me. Or if you think it really needs more clarity, we could call it "spatial volume" instead of just "volume".

> would be a good thing to include in an explanation, if you add one).
[Duckworth, Mark] We can add "Picture in Picture" at the first use, and make them all consistently "PiP" instead of sometimes "PIP".  Yes, PiPs is the plural. When tiled is mentioned it is about Endpoint A, which is shown diagrammatically in Figure 8 so I think it should be clear.