This page summarizes certain findings from the PDF Techniques Accessibility Summit conducted December 10-11, 2018 in Edinburgh, Scotland. It will be periodically updated with process changes and other details.
Email the Liaison Working Group members at firstname.lastname@example.org, or Duff Johnson at email@example.com.
Examples should be not be real-world documents. Extremely specific use-cases are preferred, in which the only content on the PDF page is that which is pertinent to the example itself. The example to the right could, for example, be used to demonstrate the right way to tag two-column content. To keep things simple, this would be the only content in the document.
In general, it’s easy to know what is and what is not correctly tagged. For example, it’s incorrect to use two (paragraph) tags enclosing different parts of a single paragraph. This fact, however, does not stop many implementations and users from getting this basic aspect of semantic structure wrong. Based on PDF/UA and WCAG 2.1, the Summit seeks to review and address not only the more difficult cases for tagging, but also to cover common cases which nonetheless generate many errors. Examples of examples for input into the summit could include:
Both conforming (accessible) and fail (inaccessible) examples are welcome. Specifically excluded as cases of examples for input are purely content-related cases such as:
There is no specific template for examples, but in addition to being extremely simple, as stated above, we do want example PDF files to be stylistically similar.
In particular, participants identified the following checklist of technical problems to be avoided in all examples created for this purpose:
To maximize the utility of Techniques examples to developers, it was determined that all examples should conform to best practices in terms of ISO 32000. Specifically, that files should exhibit conformance with not only ISO 32000's requirements, but also to its strong recommendations ("should" statements).
Roman Toda has prepared a plug in for Adobe Acrobat (both Windows and Mac!) that should help with the manual process of checking and cleaning samples to ensure they are as canonically correct as possible.
TagChecker performs a few tasks (like removing empty ClassMap entries) identified in the summit, and more improvements are possible based on requests. The software is available from Github; check the readme, download the binary, test for yourself: https://github.com/Normex/TagCheckerPI
The following best practices should be used to guide your approach to working with the Jira project for PDF Techniques development:
Any member of the LWG should feel free to email the list with questions about this process!
The summit’s workflow depends on a stream of candidate example files input by summit attendees. The process of the summit is to review, refine and disposition these examples. The workflow stages are defined as follows:
Re-create PDF examples to make them suitable for tagging.
Develop and apply the tagging technique.
LWG discussion regarding the tagging technique.
Postpone if further information/work is required
Provide further information or rework the tagging technique. The main purpose is to keep the Deliberation clean of previously-discussed cases.
Each example in the system includes the following fields. Ideally, every field would be completed for each example.
|Summary||A very concise description of the example, such as: “Page numbers”|
|Component(s)||One or more relevant subclauses from PDF/UA-1|
|Description||The purpose of the example. If it's clear from the summary you can leave this field empty.|
|Attachment||Attach the example file. Please also attach the source file, to make it easier to recreate the example if necessary!|
|Use cases||This field is optional, and may be filled as part of Deliberation|
|Concerning||Identifies all structure elements relevant to the example|
|Example type||Helps process examples from various origins|
|Reason||Used when dispositioning the example|
|AT support||AT (e.g., NVDA, JAWS) which support the example|
|Pass / Fail||Indicate if the example is an example of a passing or failing file. This field also allows for "should" and "may" values to capture best practice examples in addition to purely validity considerations.|
|PDF Technique||If applicable, indicate the relevant existing WCAG Technique for PDF|
|Matterhorn Protocol||Indicate the relevant Matterhorn Protocol checkpoint|
|WCAG 2.1 SC||Indicate the relevant WCAG 2.1 Success Criteria|
|Comment||Any additional information you want to provide|