Minutes, 12 May 2010 WebFonts WG telcon

Hello public-webfonts-wg,

 Minutes of todays call at

and below as text for trackbot.

                 WebFonts Working Group Teleconference

12 May 2010


      [2] http://lists.w3.org/Archives/Public/public-webfonts-wg/2010May/0045.html

   See also: [3]IRC log

      [3] http://www.w3.org/2010/05/12-webfonts-irc


          [Microsoft], +1.443.895.aaaa, +0845397aabb, +1.781.970.aacc,
          +1.408.536.aadd, +45.04.2.aaee, ChrisL, +1.212.381.aaff,
          [IPcaller], +45.04.2.aagg




     * [4]Topics
         1. [5]WOFF walkthrough
         2. [6]Introduction
         3. [7]Overall File Structure
         4. [8]WOFF Header
         5. [9]WOFF Header really this time
     * [10]Summary of Action Items

   <trackbot> Date: 12 May 2010

   <scribe> Scribe: Chris

   <erik> Hi everybody.

   <scribe> ScribeNick: ChrisL

   hi erik

   <erik> I muted, it might have been me. sorry.

   is the noise better?

WOFF walkthrough


     [11] http://www.w3.org/Submission/2010/SUBM-WOFF-20100408/

   JK: Do we do the Abstract as well?

   CL: Yup
   ... Is the invertibility reuirement listed in the spec?

   JK: Checking ....

   <sylvaing> 'lossless' doesn't occur again in the document

   issue: invertibility needs to be a conformance requirement

   <trackbot> Created ISSUE-1 - Invertibility needs to be a conformance
   requirement ; please complete additional details at
   [12]http://www.w3.org/Fonts/WG/track/issues/1/edit .

     [12] http://www.w3.org/Fonts/WG/track/issues/1/edit

   CL: also, "Such metadata does not affect the rendering of the font
   in any way" is a requirement

   JK: Restated in section 6

   SM: Please note in the abstract that private block does not affect
   rendering either

   AT: Yes, add that to the abstract

   JK: Third sentence is useful or not?

   AT: How do we define replacing? May well replace TT/OT on the Web

   SM: WOFF is not really a format

   AT: Analogy between multimedia formats and font formats, like codecs
   ... WOFF is a container

   "This document specifies WOFF, a container for sfnt type fonts such
   as OpenType"

   AT: that is better

   <cslye> Nice clarification, I think.

   (general agreement, no objections)

   <sylvaing> +1

   JK: Fine by me


   VL: Intro explains what sfnt is and is clearer on container

   <jdaggett> ChrisL: VL? VL perhaps?

   maybe change "directly based on the" to "a container for"

   CS: Is the compression optional?

   VL: Need to be clear on what the user agent is to do

   CL; a converter that outputs all uncompressed is conformant 9if ill
   advised) but a UA that fails to decompress is not conformant

   CS: Can we only talk about the format?

   CL: No, need conformance for UA as well

   AT: So if some data can be compressed, a user agent MUST (rfc2119)
   be able to decompress it

   VL: So a UA must decompress compressed data
   ... can recommend to authors too

   <cslye> A UA must be prepared for WOFF data to be either compressed
   or uncompressed?

   issue: add conformance for uas and generators re compression

   <trackbot> Created ISSUE-2 - Add conformance for uas and generators
   re compression ; please complete additional details at
   [13]http://www.w3.org/Fonts/WG/track/issues/2/edit .

     [13] http://www.w3.org/Fonts/WG/track/issues/2/edit

   CL: Its implied but not explicit

   AT: Table directory section interchanges WOFF file and WOFF font.
   Needs to be consistent.
   ... also distinguish between sfnt fonts and the WOFF made from it
   ... for the original sfnt fonrt, say 'font' that makes it clearer
   ... distinguish between font and WOFF file

   VL: Agreed

   AT: So replace WOFF font by WOFF file throughout

   JK: No problem

   <scribe> ACTION: Jonathan to change WOFF font to WOFF file
   throughout [recorded in

   <trackbot> Created ACTION-3 - Change WOFF font to WOFF file
   throughout [on Jonathan Kew - due 2010-05-19].

   AT: and change "compressed" to "may be compressed"

Overall File Structure

   CL: Does collection imply table ordering is maintained?

   JD: Specified later

   VL: Easier for implementors and users to make it look similar to OFF
   spec. Data types first then file structure then specific chapters on
   each part
   ... easier for people familiar with OT and OFF

   JD: Section 2 has data types defined

   VL: Maybe a more elaborate verbal descriotion before the header
   details etc

   AT: Don't folow, seems to folllow OT pretty much
   ... To me, seems quite logical from a tree approach

   VL: OK its fine, but WOFF header itself defines fields not described
   but defined elsewhere. Improve on forward referencing

   CL: Another way is to link keywords to their definitions

   VL: prefer to see every field in the header described right there

   JK: What further description would you want? e.g. for offset

   SG: So this is moving the content around, not changing it. Can we
   review the content first?

   VL: Listed in the agenda, a few changes of layout

   <erik> moving on +1

   <jdaggett> moving on +1

   SG: So the questions of sequencing are orthagonal to the actual

   AT: Happy to review Vlad's proposals

WOFF Header

   SM: Table data order can be swapped
   ... sequence of chunks is not enforced

   AT: Table directory specifies this
   ... allows tables to be ordered in different ways

   VL: Padding needs to be specified, as well as allowed order

   AT: SFNT allows padding

   JK: Blocks are mandatory, metadata must be after the sfnt and so on

   AT: "followed by" could be strengthened: "immediately followed by"

   CL; Or add "in that order" to the end of the sentence

   AT: Third para of section 2 could be strengthened

   JK: Happy to rephrase like that. No particular reason to enforce it,
   but no benefit to shuffling around either

   AT: Want to exclude black hole padding.

   <scribe> ACTION: Jonathan reword "The main body" per these minutes
   in section 2 [recorded in

   <trackbot> Created ACTION-4 - Reword "The main body" per these
   minutes in section 2 [on Jonathan Kew - due 2010-05-19].

   JK: Does say balck holes in severl places, eg "up to three bytes" so
   padding to longword boundaries only

   JD: Good to review for black holes and put something in the intro to
   that effect

   AT: Unadressed blocks are not permitted except for longword padding
   ... helps explain how the structure works
   ... implementers may not be the same folk who do font rasterisation.
   web server folks

   SM: Lack of holes should be reflected in conformance

   <Vlad> That was Sergey

   CL: Conformance on the WOFF file itself, orthogonal to UA

   SM: Data structure should be enforced, metadata out of place should
   mean the font is rejected
   ... else mno UA consistency

   SG: UAs need to all accept and reject the same things

   AT: As its a container format, strengthening relationship wth sfnt.
   Waht to do with invalid sfnt?

   SM: Talking of invalid WOFF files only
   ... can enforce from the beginning

WOFF Header really this time

   SM: Flavor can be either TT or OT but later says it can be something

   CL: Yes, in the table its 'for example'

   AT: TT and OT are the most typiczal

   Cl: AAT? Graphite?

   <jdaggett> ChrisL: those formats are defined by tables, not by the
   format tag

   AT: glyph imaging, OTTO, or line layout streams wchhis is OT layout,
   TT, SIL Graphite or others
   ... so flavor is really the glyph flavor
   ... line layout flavor is not specified in the header

   CL: So does it need two fields?

   AT: No
   ... may have multiple tables in the font, so its up to the layout
   engine what it uses

   JD: no need to over specify, defer to the OT and OFF specs

   AT: So remove excess wording from tables into the prose

   <cslye> Gotta run, everyone. Thanks.

   <scribe> ACTION: Jonathan to make proposals to the mailing list for
   points raised on 12 May call [recorded in

   <trackbot> Created ACTION-5 - Make proposals to the mailing list for
   points raised on 12 May call [on Jonathan Kew - due 2010-05-19].

   AT: Could we all review the whole spec for next week and sent in a
   prioritised edit list

   VL: Also, can we classify proposed changes as general, or technical
   (specific sections) or editorial (readability etc)

   (general agreement)

   <erik> okidoki. have a good trip!


Summary of Action Items

 Chris Lilley                    mailto:chris@w3.org
 Technical Director, Interaction Domain
 W3C Graphics Activity Lead
 Co-Chair, W3C Hypertext CG

Received on Wednesday, 12 May 2010 21:07:39 UTC