I'd add one additional comment about PDFs. PDFs do not deal with actual letters and characters, rather they deal with sequences of glyphs. PDF documents may not contain the actual text. Nor may the fonts contain well formed cmap tables. This will impact on accessibility of the document.
Probably not a concern with Microsoft Word where lots of the OpenType specification is non-functional, but will be an issue with applications and documents that make use of the OpenType GSUB tables in some fonts and use alternative glyphs or ligatures within a document. Esp. if the \ToUnicode or \ActualText data is not present in the PDF. Andrew On Sat, February 23, 2008 4:57 am, Steve Green wrote: > PDFs can be more accessible than was previously possible but there are > lots > of gotchas, and it's way too big a topic to cover in this reply. Note that > by default, PDFs are not tagged, so they are only marginally more > accessible > than before. Maximum accessibility is obtained by tagging them, but that's > where it gets hairy. > > To start with a lot depends on what application your document was authored > in. If it was authored in Word (and a small number of other applications), > any semantic structure that you have implemented by means of paragraph > styles will be carried over to the PDF. If it was authored using graphical > applications such as Quark and Photoshop, not only is there no semantic > structure, but the reading order is likely to be wrong because these > documents are frequently made up in layers with no consideration of how > they > will linearise. > > Tagging can be conducted automatically, using the Autotagger, but the > results are highly variable. I have never seen a document that could be > used > without manual adjustment of the tags. In many cases it is actually easier > to manually tag the entire document and not use the Autotagger. In fact we > always do this, but that may be a reflection of the complexity of the > documents we get asked to handle. > > If the source document does not contain semantic structure, the Autotagger > uses heuristics to make a best guess. This sometimes comes close but often > doesn't. There is a tendency for it to mark up multiple columns of text as > tables, and background colours or images can confuse it. > > Both Acrobat 7 and 8 are pretty buggy, and the Accessibility Checker in > Acrobat 7 sometimes reports faults when there aren't any. In our opinion > the > user interface in Acrobat 7 is much better than version 8 so we often use > both for different parts of the job. > > Forms are a lot of fun. The user cannot save the document with the data > they > enter in the form, but it is still worth making forms accessible so they > can > be filled in and printed. There are ways to submit the forms online but > there are significant licensing issues (it's ages since I looked into > this, > so I can't recall the detail). > > Even after making your best efforts, a PDF will not be as accessible as a > properly marked-up HTML page with the same content. There are some > resources > out there but my recollection is that they all deal with the ideal > scenario > that you are creating new documents in Word or InDesign. There are some > resources below, and they link to other useful stuff. > > http://www.brucelawson.co.uk/2006/accessible-pdfs/ > > http://alastairc.ac/2006/07/the-four-levels-of-pdf-accessibility/ > > http://alastairc.ac/2007/08/comparing-tagged-pdfs-from-office-and-acrobat/ > > > For those who want someone else to take all these problems away, we offer > a > PDF accessibility service - http://www.labscape.co.uk/accessible_pdfs.htm, > and we also provide training for mad people who want to do it themselves. > > Steve > > > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of McLaughlin, Gail G > Sent: 22 February 2008 16:57 > To: [email protected] > Subject: [WSG] PDF Accessibility > > I have a client who discourages the use of PDF forms and files on their > website because they believe that they are not accessible. > > Researching this on the Web, it appears that this may have been true > several > years ago, but that Adobe has made an effort to make PDF forms and files > accessible in Adobe Acrobat 7.0 and 8.0. > > Are PDF forms and files created with Adobe Acrobat 8.0 truly accessible? I > assume that certain protocols must be followed to assure accessibility, > just > as there are protocols to assure accessibility of HTML files. > > Can anyone direct me to a good resource detailing what protocols one must > follow to assure accessibility of PDF forms and files? > > Thanks much, > Gail > > > > ******************************************************************* > List Guidelines: http://webstandardsgroup.org/mail/guidelines.cfm > Unsubscribe: http://webstandardsgroup.org/join/unsubscribe.cfm > Help: [EMAIL PROTECTED] > ******************************************************************* > > > > ******************************************************************* > List Guidelines: http://webstandardsgroup.org/mail/guidelines.cfm > Unsubscribe: http://webstandardsgroup.org/join/unsubscribe.cfm > Help: [EMAIL PROTECTED] > ******************************************************************* > > -- Andrew Cunningham Research and Development Coordinator Vicnet State Library of Victoria Australia [EMAIL PROTECTED] ******************************************************************* List Guidelines: http://webstandardsgroup.org/mail/guidelines.cfm Unsubscribe: http://webstandardsgroup.org/join/unsubscribe.cfm Help: [EMAIL PROTECTED] *******************************************************************
