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Measuring PDF AccessibilityPDF a11y Testing for the Rest of Us
@dboudreaua11yCamp DC 2013Deque Systems, Inc.
Are you losing the war on inaccessible PDFs?
PDF AccessibilityWhat’s YOUR Strategy?
Anybody Feeling Helpless?
We’ve all read those comments before…
PDF Documents Suck!
…and no matter how often we read them…
Use Semantic HTML Instead!
PDF Documents Suck!
…it still comes down to the same thing…
<Insert_Other_Hateful_Comment_Here>
Use Semantic HTML Instead!
PDF Documents Suck!
Haters Gonna Hate…
Stop complaining. PDFs aren’t going anywhere.
Learn to deal with them instead.
WHO CARES WHAT I, YOU, OR ANYONEELSETHINKS ABOUT PDFs?
Measuring PDF Accessibility
* All about learning basic PDF a11y “self-defense” techniques.* No different than testing regular HTML pages against WCAG 2.0. * Based on the exact same W3C accessibility guidelines.
By the way…It’s ok to feel clueless!
?
Breaking News!Not Everyone is a PDF Expert!
Shocking Truth!Not Everyone has access to a PDF Expert 24/7!
In fact, some people even pretend that…
PDF Accessibility TestingA Proposal For the Rest of Us(Or how to fake your way into looking like a PDF expert in 15 easy steps)
Some Tools to Consider Adobe Acrobat Pro XI Accessibility Checker
Runs on both Windows and MacOsMost convenient option to validate PDF accessibility
CommonLook PDFPlugin for Adobe Acrobat on WindowsAvailable at http://www.commonlook.com/CommonLook-PDF
PDF Accessibility Checker 2 (PAC2)Runs on Windows (no need for Adobe Acrobat or Reader) Available at http://www.access-for-all.ch
Screen readers!?We don’t wannause no stinkin’screen readers!!!
Though admittedly, that would really help… but between you and me, you can also leave it to the “experts”.
Image-Based Documents
Is the PDF document made up of scanned images instead of text? Report the document can’t be tested
for accessibility until there is actual text to work with (OCR might be the best option).
Minimally report issues related to access restrictions, default language identification and document title (if any).
A
Text-Based Documents
Is the PDF document text-based and can all text be selected? If the document is text-based, you
are ready to start faking your way up the PDF Accessibility Ladder.
If the document is image-based, send the author directly to “jail”. (if he passes GO, he doesn’t collect $200)
B
Faking Your Way Up the PDF a11y Ladder
1. Access Restrictions2. Default Language3. Document Title4. Bookmarks5. Content Reflow6. Tagged Structure7. Semantic Structure8. Tabbing Order9. Informational Images10. Decorative Images11. Meaningful Hyperlinks12. Page Numbering13. Running Header and Footers14. Data Tables15. Form Fields
A 10,000 ft. View
Step Technique WCAG SC
Access Restrictions -- 4.1.2
Default Language PDF16 3.1.1
Document Title PDF18 2.4.2
Bookmarks PDF2 2.4.1
Content Reflow -- 1.4.4, 1.4.8
Tagged Structure -- 1.3.1
Semantic Structure PDF11, PDF21 1.3.1, 4.1.2
Tabbing Order PDF3 2.1.1, 2.4.3
Informational Images PDF1 1.1.1
Decorative Images PDF4 1.1.1
Meaningful Hyperlinks PDF11 2.4.4
Page Numbering PDF17 2.4.5
Running Headers & Footers PDF14 2.4.5
Data Tables PDF6 1.3.1
Form Fields PDF12, PDF23 1.3.1, 3.3.2
Access Restrictions
Are there any access restrictions on the PDF, such as password protection?
In Acrobat, open the Document Properties dialog box, go to the Security tab and make sure the “Enable text access for screen reader devices” option is checked.
Default Language
Is the natural language of the PDF document specified?
In Acrobat, open the Document Properties dialog box, go to the Advanced tab and look for a language indication under “Reading Options”. Make sure the language indication correctly identifies the language the content is in.
Document Title
Does the PDF have a meaningful and descriptive title (not just a file name)?
In Acrobat, open the Document Properties dialog box, go to the Description tab and look for a descriptive title in the title field.
Bookmarks
Does the PDF contain bookmarks and are they helpful for navigating efficiently to various sections of the document?
In Acrobat, look under the Bookmarks panel to see whether the document contains bookmarks. Make sure they actually allow the user to jump to specific sections of the document.
Content Reflow
When Reflow mode is activated, does all the content reorganize naturally in a single, easy to read column?
Enable Content Reflow in Acrobat or Adobe Reader, make sure the content reflows into a single full width column and that no content is lost.
Tagged Structure
Is the PDF structure tagged and are these tags correctly identified?
In Acrobat, look under the Tags panel to see if the documents actually contains tags. Untagged documents should be reported for language, title and permission issues (if any), and declared inaccessible.
Semantic Structure
Is content organized consistently using semantically and correctly structured markup?
In Acrobat, look under the Tags panel to see if elements that are visually presented as headings, paragraphs, lists and such are also marked up accordingly.
Tabbing Order
Can the document be navigated in a logical order that is consistent with the meaning of the content?
Using the keyboard, tab through the PDF to determine if the tabbing order allows for a logical reading order. Make sure form controls allow for keyboard interaction.
Informational Images
Does the text alternative provided for every informational image convey the same meaning or purpose as the image?
In Acrobat, use the TouchUp Reading Order dialog box to validate that an equivalent text alternative has been provided for images that do convey information.
Decorative Images
Are purely decorative images marked up as artifacts, so screen readers can safely ignore them?
In Acrobat, use the TouchUp Reading Order dialog box to validate that all decorative images have been turned into artifacts (background images).
Meaningful Hyperlinks
Is hyperlink text marked up using Link annotations and is the purpose of that text meaningful?
In Acrobat, look under the Tags panel to make sure link tags all have a Link-OBJR tag assigned to them. Make sure the purpose of each link can be determined out of its immediate context.
Page Numbering
Does page numbering differ from the numbering displayed in the viewer page controls?
Go through the document and verify that the page numbering in the PDF is identical to the numbering in the PDF viewer page control.
Running Headers & Footers
Are running headers and footers provided consistent with existing section headings?
Go through the document and verify that the information provided in running headers and footers is consistent with the section headings.
Data Tables
Are the tables contained in the PDF marked up properly and are header cells and data cells explicitly associated?
In Acrobat, use the TouchUp Reading Order dialog box to validate that tables are marked up correctly and that data and header cells are explicitly associated.
Form Fields
Can assistive technologies gather information about and interact with form controls in PDF content?
In Acrobat, for each form control, select the corresponding Properties Dialog box and make sure a value has been added to the tooltip field.
A Reminder PDF Accessibility
* As you can see, basic PDF a11y testing is not rocket science.* Have basic accessibility knowledge? Then you can test PDF documents.* Know WCAG 2.0? You’re already familiar with the PDF techniques.
A Light at the End of the Tunnel?So get out there and document those issues!
Keep Calm and Hug a PDF
PDFsShow ‘em who’s boss!
You can do it!
Merci beaucoup!
Denis BoudreauWeb Accessibility Avenger
Deque Systems, Inc.@dboudreau
Photo Creditshttp://www.flickr.com/photos/krawcowicz/4153762400/
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http://www.flickr.com/photos/janelacastillophotos/5774176179/
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http://www.keepcalm-o-matic.co.uk/p/keep-calm-and-hug-a-pdf/
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http://www.flickr.com/photos/11391549@N02/2405054957/
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