Tagged Adobe Pdf, Read Order, And Reflow - Adobe 22020772 User Manual

Tagged Adobe PDF, Read
Order, and Reflow
Adobe is committed to providing solutions that improve accessibility to infor-
mation contained in Adobe PDF files by enhancing support for assistive
technology such as screen readers through the MSAA API for the Windows
platform.
Tagged Adobe PDF is a version of PDF that provides structure and order infor-
mation to allow PDF documents to be read by screen readers.
The major requirements for accessible documents covered in this volume are:
For a screen reader to effectively read information on a
Logical reading order
page, clues must be provided to help it determine in what order the text on the
page is meant to be read. This order can be ambiguous in the case of multi-
column text, side bars, pulled quotes inserted in the middle of or between
columns, tables, and the like. By tagging and identifying the various blocks of text
and other page elements that make up the layout, tagged Adobe PDF provides a
means of supplying these clues, and defining the intended read order of the page.
Graphic representations such as illustra-
Alternate text descriptions for images
tions, drawings, charts and graphs cannot be interpreted by a screen reader. By
supplying description text for images, a screen reader can describe to a visually
impaired user the information the image is meant to impart.
Although current screen readers are designed to read
Document language
documents based on one language dictionary, it is anticipated that future
technologies will be able to access multiple language dictionaries. For this reason,
the specification of the document language is considered a requirement for
providing accessible documents online. Acrobat 5.0's Accessibility Checker will
log an error if the document language is not specified.