Subject: Proposed liaison statement to SC 29

From: Steve Carson <[email-masked]>
Date: Fri, 17 Oct 1997 11:56:01 -0600

This is a proposed liaison statement to SC 29 that is based on work done by
several of our experts with their MPEG-4 BIFS (Binary Format for Scenes) Ad
Hoc over the last month. It summarizes various offers, positions,
approaches and proposed agreements that have been circulated and discussed
on the MPEG-4 and VRML reflectors. This is input that SC 29 has asked us to
submit to the Plenary meeting of SC 29/ WG 11 to be held 27 - 31 October in
Fribourg, Switzerland.

Lets have any discussion that we need on this on this reflector. I propose
forwarding this to SC 29 on Friday morning 24 October (European time), so
if there are any objections lets hear them by Thursday 23 October at 1700 CET.

- - -
This is a joint statement from ISO/IEC JTC 1/SC 24 and the VRML Consortium to
ISO/IEC JTC 1/SC 29. It has been approved by both the P-members of SC24 and
by the Board of Directors of the VRML Consortium.

ISO/IEC JTC 1/ SC 24 N XXXX (Number to be added before it is sent.)

Date: 24 October 1997

Title: Second Joint Statement from ISO/IEC JTC 1/SC 24 and the VRML
Consortium to ISO/IEC JTC 1/SC 29

First, we want to thank SC 29, its WG 11 and in particular the Ad Hoc Group
on Binary Formats for Scenes (BIFS) for the cooperation it has shown
throughout our recent mutual discussions regarding the application of VRML
(DIS 14772-1) within MPEG-4. Both ISO/IEC JTC 1/SC 24 and the VRML
Consortium are encouraged by the progress made to date in resolving
problems with the manner in which earlier Working Drafts of the BIFS sought
to utilize VRML. Both JTC 1/SC 24 and the VRML Consortium are committed to
continuing work with SC29 to insure that proper, normative references to
DIS 14772-1 (VRML) are made within CD 14496-1, MPEG-4 Systems, Scene
Description.

Based on the ongoing technical discussions that our respective experts are
holding, we believe that the following points define an appropriate
cooperative framework for further cooperative work:

1) MPEG-4/BIFS is a conforming application of DIS 14772-1 (VRML).

2) MPEG-4/BIFS conforms to the abstract syntax defined in DIS 14772-1.

3) MPEG-4/BIFS is free to define one or more "generator profiles" that
restrict those elements of DIS 14772-1 that are used in MPEG-4/BIFS data
streams.

4) There is a single binary encoding for VRML (which we offer to jointly
develop with SC 29 and which will become both an ISO/IEC Standard and a
VRML Consortium Standard).

5) MPEG-4/BIFS fully conforms to DIS 14772-1 semantics.

We note that no special processes or procedures are necessary for SC 29 to
apply DIS 14772-1 (VRML) to the MPEG-4/BIFS application by normative
reference in accordance with Clause 7 of 14772-1. On the other hand, we
believe that there are substantial benefits to both communities if other
ongoing work could be accomplished cooperatively.  This would begin with
the development of a binary encoding of VRML where we have the opportunity
to combine work in process within SC 29 with that in process within the
VRML Consortium and SC 24 to produce a single binary encoding.  We believe
that the following points define a cooperative framework for this future
cooperative work:

1) All work is to be accomplished in accordance with the terms of the
approved Cooperative Agreement between the VRML Consortium and both ISO and
IEC.

2) When required to meet unique circumstances, amendments to the
Cooperative Agreement will be developed and agreed to by all three parties
(SC 29, SC 24 and the VRML Consortium.)

3) All three parties agree to clearly identify any Intellectual Property
Rights that are or will be asserted by any owners of MPEG-4 or VRML
technologies at the time that such technologies are first submitted for
consideration as joint, cooperative work.

4) SC 29 and SC 24 mutually agree to joint circulation within both
committees of WD text and to joint balloting within both committees of CD
text for all documents to be developed under this cooperative framework.
This includes, but is not limited to, future amendments to DIS 14772-1
(VRML), the binary encoding of VRML (whether it becomes a part of the VRML
standard or a part of the MPEG-4 standard), and MPEG-4 Scene Description
(CD 14496-1). We note that the terms of the Cooperative Agreement already
prescribe coordinated procedures between ISO/IEC JTC 1 and the VRML
Consortium.

Finally, we thank SC 29/ WG 11 for taking initial steps to comply with the
request made in our previous liaison statement (ISO/IEC JTC 1/ SC 24 N
1766,  Joint Statement from ISO/IEC JTC1/SC24 and the VRML Consortium to
ISO/IEC JTC 1/SC 29, dated 14 July 1997) to remove improperly used,
copyrighted material from your Working Drafts. We note that we have now
granted SC 29/ WG 11 permission to retain this material in your Working
Drafts to aid in dialog with VRML experts to convert BIFS to a proper VRML
application. 

We reiterate our position that all such improperly material must be
completely removed in the published CD version of 14496-1 (that is, the
version that is circulated for first CD ballot within SC 29) and that no
normative text from DIS 14772-1 be repeated within CD 14496-1 except those
brief portions required for expository purposes, such as in describing a
conforming extension that is prototyped on an existing VRML node. The
removed material is to be replaced with a normative reference to the
appropriate material within 14772-1.
Further, should our mutual efforts to convert BIFS into a conforming VRML
application fail, we insist that BIFS be modified so that it is not a
"derivative work" of VRML. 

signed:

Steve Carson                               Neil Trevett
Chair, ISO/IEC JTC 1/SC 24                 3D Labs
Computer Graphics and Image Processing     President, VRML Consortium

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Steve Carson                 phone:   +1-505-521-7399
GSC Associates Inc.          fax:     +1-505-521-9321
5272 Redman Road             e-mail:  [email-masked]
Las Cruces, NM 88011 USA
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