PNG Chunk Registration Process, draft 19960924
Status of this Memo
This document is an informal draft of the PNG development group.
Comments on this document can be sent to the PNG specification
Distribution of this memo is unlimited.
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Copyright © 1996 Thomas Boutell
Permission is granted to copy and distribute this document for
any purpose and without charge, provided that this notice is preserved,
and that any substantive changes or deletions from the original are
This document describes the approval process for registering
public PNG chunks. Persons who have contributed to the PNG mailing list
at least 180 days prior to the end of the voting period are eligible
to vote. A two-week voting period follows a two-week discussion
period. Votes are cast by electronic mail to the png-list mailing list.
Approval of a chunk registration requires at least 10 YES votes with at
least twice as many YES votes as NO votes.
Table of Contents
To formally approve or reject a chunk for registration as a public chunk
as described in the PNG 1.0 specification. This method can also be used to
resolve other issues that need to be decided by the PNG group.
Discussions on the PNG discussion list (email@example.com) at
present fail to reach a clear consensus on the desirability of particular
chunk definitions. The formal approval process is intended to aid such
To meet these ends the formal process is based on a discussion and
voting process exercised over a limited period of time.
Identifying consensus when it exists.
Giving a limited time period within which objections can be raised.
Encouraging discussion and preventing ambiguities when one party to the
discussion simply falls silent.
Voting can be initiated after a two-week discussion period. The proposed
chunk specification must be available and must not
change for a period of at least two weeks before a vote can be called for.
The chunk proponent starts this clock running by notifying the list that
the proposed specification is available. Short proposals should also be posted
to the list, to save people the trouble of downloading them. If
discussion exposes flaws, the specification can be revised, thus starting a new
two-week discussion period.
A proposed specification of the chunk must exist in electronic form in a
on the current png-group discussion list FTP server (at present this is the
tree based at ftp://swrinde.nde.swri.edu/pub/png-group/).
The proposal must be in a final publishable format, such as that of the
PNG specification and PNG extensions document.
The specification can either be a whole single file, or group of files
(which must be named by single ftp accessible directory name and implies all
files in that directory and all directories beneath it) or an identified
part of a single file.
The specification should describe the proposed chunk in its unregistered form,
to avoid the risk of premature distribution of documents describing
public chunks that are not in their final form.
The editors will make the necessary changes to the final document, by
changing the second letter of the chunk name to uppercase and by removing
any private version identification. If any other changes are needed,
instructions to the editors should be provided in the proposal.
The specification or the call for votes must state the proposed
disposition of the registered chunk:
Note that the names of all formally registered chunks
will either appear in the PNG specification or in the PNG extensions document.
The editors will make the appropriate changes to those documents when a
chunk is registered.
Inclusion in the PNG core specification
Inclusion in the PNG extensions document
Inclusion in an existing separate document
Inclusion in a new separate document
Throughout the two-week voting period the specification must remain
absolutely unchanged. The two-week discussion period must be restarted
upon making any change to the proposed specification, except for
Upon the objection of any voter, received by the png-list server prior to
the call for votes, the two-week discussion period must be restarted in the
event of any such change.
Simple formatting, grammatical, or spelling changes.
A printing date or authorship change.
After the two-week discussion period, the vote is initiated by any person
submitting the first YES vote on an identified specification, using the
format suggested above, clearly identifying the specification to be voted
Votes are cast by sending a message to the png-list indicating a YES, NO,
vote. Voters should take care to make their intentions clear (i.e. "YES" or
"NO" and precisely what chunk specification is being voted on). To ensure
that a vote is correctly registered the following form, as the first lines of
an e-mail message, is suggested:
Glenn Randers-Pehrson <firstname.lastname@example.org>
The vote-takers can accept votes that do not adhere exactly to this
format as long as the intent is clear.
There should be no other topics of discussion in the same message. An
"Oh, by the way, I vote NO on cNEW" buried in the text of a long message
might get overlooked. It is acceptable and useful to include additional
explanations in the message, but the vote itself should be placed
at the beginning.
The subject of the message must contain the word "VOTE" (in uppercase
letters), the word "YES" or "NO" or "ABSTAIN" (in uppercase letters),
and the name
of the proposal being voted upon, and the string "Re:" must not not appear
in the subject. An example of a correctly formatted subject line is
Subject: I VOTE YES on cNEW 19991231.
Only one vote should be included in a message. If a group of chunks is being
voted on as a whole, then only one message is necessary, but if
different chunks are being separately voted upon during the same period,
separate messages are required. The decision whether to group or separate
chunks for voting is up to the person casting the initial YES vote.
A person can submit a changed vote any time prior to the expiration
of the voting period. Only the latest vote, determined by the time it
was mailed by the voter (from the "Date:" field of the message), that
is received by the png-list server prior to the expiration of the
voting period, will be counted. ABSTAIN votes are not counted. A person
can cast an ABSTAIN vote to withdraw a YES or NO vote without having to
cast a NO or YES to countermand it.
The voting period ceases two weeks after the initiation, at the same
time of day as the initiation.
The time of the call for votes is determined by the
"Received:" line generated by the png-list e-mail server, e.g. in the
"Received: from grommit.inria.fr (grommit.inria.fr [22.214.171.124]) by
dworkin.wustl.edu (8.6.10/8.6.6.yuck) with ESMTP id KAA10764 for
<email@example.com>; Sun, 22 Sep 1996 10:11:58 -0500"
the date and time are "Sun, 22 Sep 1996 10:11:58 -0500", and the
voting period ends on Sunday, 06 Oct 1996 10:11:58 -0500.
The voting period also ceases immediately and the proposal is rejected if
all YES votes are countermanded by NO or ABSTAIN votes from the
voters originally casting the YES votes.
The voting period ceases immediately and the proposal is rejected upon
approval of a competing specification for same chunk name.
Votes will be tallied and interpreted by a group of [3?]
vote-takers, to be selected by consensus for life-time appointment from
among volunteers. [Who counts the votes if we want to impeach the
A chunk specification is approved if both of the following conditions are met
at the end of the voting period:
If these conditions are met, then the chunk immediately becomes registered and
people can start using it in its registered form. The PNG editors will
include the chunk specification, or a reference to it, in the next release
of the PNG documentation.
Ten YES votes are received.
At least twice the number of YES votes as NO votes are received.
If these conditions are not met the chunk specification is rejected. A
further vote requires either a 180-day waiting period, to allow for
implementation and testing, or a substantial change to the definition as
Anyone is eligible to vote who has:
Adoption of this procedure for registering PNG chunks will be voted upon
using the same procedure as used for approving a chunk registration. It
will take effect immediately upon the successful completion of the required
discussion and voting periods. Discussion periods for proposed chunks,
but not voting periods, can run concurrently with the voting period for
adoption of this procedure.
Submitted their first (or any subsequent) message to the png-list at
least 180 days before the termination of the voting period.
The procedure described in this document can also be used for registering
chunks in related formats such as MNG, provided it is separately adopted
for use for the other format. The votes will be called for
and cast using the appropriate mailing list (e.g. mpng-list) instead of
End of PNG Chunk Registration Process document. Expires 24 Mar 1997.