Minutes of the June PWG XHTML-Print meeting
Minutes of the June PWG XHTML-Print meeting
Hilton Portland, Portland, Oregon
June 24, 2002
II. Review and Approve minutes from April
III. Review status of open issues and action items from minutes
i) CSS Attributes Proposal from Melinda and Elliot
IV. Review of xhtml version of the document
V. Discussion on Canon's request to reorganize the specification
VI. W3C Device Independent Working Group and its effect of XHTML-Print
(http://www.w3.org/2002/06/w3c-di-wg-charter-20020612.html note: section5.2.5)
VII. New Issues
i) Using Multiple Style Sheets
Jim Bigelow agreed to be the minute taker for the meeting.
Review of minutes from April meeting
Accepted as distributed
Review of XHTML Attributes categorization:
Melinda Grant and Elliot Bradshaw examined each of the relevant XHTML attributes and
categorized them into:
- Required – a conforming printer must support an attribute marked required
- Optional – a conforming printer does not have to support such an attribute and
any support is implementation dependent.
- Ignored – these attributes are not meaning full when printing.
Note: a revised version of the attribute-spread sheet was distributed the Friday before the
meeting so participants had not had time to review it. A discussion of some of the
attributes marked "optional" occurred with the understanding that the committee would
discuss and decide how all the attributes should be handled in subsequent
|action, cols, enctype,
method, rows, tabindex,
Consideration of this attribute and others directly related to
supporting the Basic Forms module showed some difficulties
with printing a representation of a form. Printing a blank
form or a form containing the default values is not difficult.
The problem comes up when considering a use case where
users would like to fill out a form and print it, as filled out, for
a record or confirmation of a transaction. XHTML-Print
support for this use case is not possible within the
specification of XHTML-Print constructs since the data
entered into the form by the user is not part of the language,
rather it is a separate data stream. |
The entity presenting the form can avoid the problem by
presenting an information page integrating the user's data and
Melinda Grant suggested that only minimal support for
printing a blank form be mandated in the language since there
is no method within the language to merge the user data and
Jacob Refstrup suggested that the user data and form could be
transmitted to the printer in a multi-part/multiplexed data
stream in a manner similar to the transmission of inline data.
The suggestion is this attribute is optional since UTF-8
handles character set specification. The manner that a
conforming printer handles this attribute is implementation
Classid & codetype
The suggestion is one attribute is supported they must both be
Support for this attribute is optional since low memory device
any not be able to honor the intent of attribute – to store the
image for later reference.
Make jpeg baseline the minimum requirement
The rationale for suggesting this be optional was not available
during the discussion, in its absence the suggestion is to make
Review of xhtml version of the document
- Melinda Grant is leaving the committee so there is an opening for an editor for the
- The question of how to keep a document change history was raised. One
possibility is to add a change history to the end of the document. Jacob Refstrup
suggested that a version of the wdiff tool for finding and marking differences
between to html documents would be very useful now that the specification is in
Action Item: Jacob Refstrup will locate and make available a version of a tool to find
and mark differences between two html documents.
- The question of where in the specification to put the annotated list of attributes
that Melinda Grant and Elliot Bradshaw created was discussed. Suggestions for a
separate appendix or placement in the conformance section (2.3.2) were put
Action Item: Don Wright is to decide where in the specification the attributes will be
- Section 2.3.2, item 8. The example, "" is a character reference not an
Action Item: Don Wright will replace the character reference with an entity
- Melinda Grant asked how to keep the conformance section of the document
(Section 2.3) in step with w3c specs. The discussion that followed weighted the
value of a stable specification against the redundency of restating other
- Do more research on how the w3c documents handle this issue.
- Weight the pros and cons of two techniques:
- Restate the conformance requirements in force at the time the spec is
issued with changes and requirements necessary for XHTML-Print.
- Simply refer to basic conformance requirements inherited from referenced
documents and only state the exceptions, changes, and XHTML-Print
Canon's request to reorganize the specification
There were two parts to the proposal to restructure the specification:
- The intent to specify XHTML-Print as a composition of four components: 1) a base
element spec, 2) a base style spec, 3) and additional style spec, and 4) image rotation;
- EXIF markers in the image are not the way to indicate the orientation of the image on
The discussion of how to organize the specification can be summarized as
- There is no base sufficient for printing: XHTML Basic is not sufficient for
printing: it lacks support for text presentation, and style. Therefore, creating a
specification from the modules defined in Modularization of XHTML is clearer
than using XHTML Basic as the starting point. Furthermore, CSS-Mobile is
focused on presentation on a display such as a cell phone rather than a printed
page, which makes it a difficult place to base a specification for pagination and
- There is w3c work in progress on the modularizing CSS, but it is not available
- More work needs to be done to complete the specification of the CSS properties
and selectors needed for printing.
The discussion of how to specify an image's orientation can be paraphrased
- All parties would like the w3c to specify a way to state how an image is oriented
on the page, rather than have the orientation within the image header.
- There is work in progress by the w3c to create a way to specify orientation but not
arbitrary rotation, i.e., only rotation at 90-degree intervals. This work is specific
to images and not to the CSS box layout algorithm.
- All parties would like to have rotation of images. Melinda Grant suggested
support for orientation in the near future and rotation at some later date is
Action Item: Canon will bring up the issue of image rotation with the w3c so that a
w3c approved method can created and used in the XHTML-Print specification. In the
interim the processing of EXIF marker will be optional.
- The interaction with EXIF markers and a not yet developed CSS property for
specifying the orientation/rotation of the images was discussed. What if the EXIF
marker exists and the CSS property is or is not there?
Action Item: post the issue for discussion of the PWG XP mailing
list for 2 weeks.
W3C Device Independent Working Group and its effect on
The mission of the W3C Device Independent Working Group is to study issues related to
authoring, adaptation and presentation of Web content and applications that can be
delivered effectively through different access mechanisms. The group's charter (Section
5.2.5 Printer related groups) names the PWG XHTML-Print committee as the body
responsible for the definition of print markup (XHTML-Print) and printer capability
Using Multiple Style Sheets
The link element can be used to include one or more style sheets in a document.
Depending on the attributes within the link element the style sheet:
- will always be applied,
- only applied to the named media, e.g., print or screen,
- be one of a set of alternate sheets that the user can choose from, and finally,
- the preferred alternate style sheet.
The consensus is that:
- Link elements referencing style sheets for media other than print, e.g., screen
should be ignored.
- The use of alternate style sheets is discouraged and a conforming printer's
response to alternate style sheets is implementation dependent.
- If there is a set of alternate style sheets that are not ignored by rule 1 above,
and a preferred style sheet exists, the preferred sheet will be used and the
remainder of the alternate sheets ignored. If multiple preferred sheets exist,
the first one encountered will be used.
Action Item: Jim Bigelow will write a paragraph for the XHTML-Print specification
dealing with multiple style sheets in a document.
Work on running page headers and footers and CSS level 2.1
Jacob Refstrup is attending CSS meetings and reports that:
- The model for specifying running headers and footers is changing. The previous
model allowed the side margin boxes to overlap the header and footer margin
boxes so that text in the boxes could overlap. The new model is similar to a table
row and will avoid overlapping area. Jacob Refstrup is the lead editor for the new
proposal that will be presented at the next CSS meeting in late August.
- Work on a CSS 2.1 specification is on-going. CSS 2.1 does not contain the
@page rule since w3c candidate recommendations must be testable and @page
cannot be tested at the time. Therefore, the @page rule will be moved to CSS
Level 3 (AKA current work)
XSL Formatting Objects and XHTML-Print
XSL (eXtensible Stylesheet Language) is a markup language for formatting material to
media such as a page. XSL contains 51 formatting objects and 231 properties for
configuring the formatting objects.
Harry Lewis called for a consideration of the relationship of XSL formatting objects and
XHTML-Print. The consensus was that XSL is too complex for low cost printers to
Future work and directions for the CSS portion of the XHTML-Print
Melinda Grant called for a consideration of how to deal with the CSS material now in the
XHTML-Print specification since it is not complete. The discussion evolved into a
consideration of the structure of the XHTML-Print specification and ended with the
proposal that the specification be broken into the following separate
- CSS Print Profile – a specification defining a subset of CSS level 2 plus elements
of CSS level 3 tailored to the needs and constraints of printing devices.
- XHTML Print – a specification of a subset of the XHTML 1.0 designed for
printing in environments where it is not feasible or desirable to install a printer-
specific driver and where some variability in the formatting of the output is
- XHTML + CSS: A Profile for Printing – a specification referencing: XHTML
Print, the CSS Print Profile, JPEG Decoder requirements, and
Inline Image Data requirements.
The first two documents, CSS Print Profile and XHTML Print, could be the responsibility
of the w3c. The last document, "XHTML + CSS: A Profile for Printing," would be the
responsibility of the PWG.
Action Item: Jacob Refstrup will write the first draft of "CSS Print Profile." Don Wright
will write drafts of the other two documents: "XHTML Print" and "XHTML + CSS: A
Profile for Printing"
Conversion of the XHTML-Print DTD to an XML Schema
Work is continuing with the conversion w3c documents to an XML schema. When the
conversion is complete, the DTD can also be easily converted.