Operation Manual

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USING ACROBAT X STANDARD
Accessibility, tags, and reflow
Last updated 10/11/2011
• Show Audio Description (Or Video Description, Or Descriptive Video) When Available
These preferences don’t correspond to any options in the Accessibility Setup Assistant.
Accessibility preferences in Page Display panel
Zoom Sets the on-screen magnification of documents and allows low-vision readers to read reflowed PDFs more
easily. This preference corresponds to the Override Document Zoom option in the Accessibility Setup Assistant.
Smooth Text Controls anti-aliasing of text. To disable smoothing of text and make text sharper and easier to read with
a screen magnifier, choose None. This preference corresponds to the Disable Text Smoothing option in the
Accessibility Setup Assistant.
Accessibility preferences in Reading panel
Reading Order Specifies the reading order of documents. The reading order preferences also appear in the
Accessibility Setup Assistant.
• Infer Reading Order From Document (Recommended) Interprets the reading order of untagged documents by
using an advanced method of structure-inference layout analysis.
• Left-To-Right, Top-To-Bottom Reading Order Delivers the text according to its placement on the page, reading
from left to right and then top to bottom. This method is faster than Infer Reading Order From Document. This
method analyzes text only; form fields are ignored and tables aren’t recognized as such.
• Use Reading Order In Raw Print Stream Delivers text in the order in which it was recorded in the print stream. This
method is faster than Infer Reading Order From Document. This method analyzes text only; form fields are ignored
and tables aren’t recognized as such.
Override The Reading Order In Tagged Documents Uses the reading order specified in the Reading preferences
instead of that specified by the tag structure of the document. Use this preference only when you encounter problems
in poorly tagged PDFs. This preference corresponds to the Override The Reading Order In Tagged Documents option
in the Accessibility Setup Assistant.
Page Vs Document This preference determines how much of a document is delivered to a screen reader at a time. If a
PDF isn’t tagged, Acrobat may analyze the document and attempt to infer its structure and reading order, which can
take a long time for a long document. You may want to set Acrobat to deliver only the currently visible page so that it
analyzes only a small piece of the document at a time. This consideration will vary depending on the size and
complexity of the document and on the features of the screen reader. When Acrobat delivers information to a screen
reader, screen magnifier, or other assistive software, it loads information into a memory buffer that is directly available
to the assistive software. The amount of information that is delivered to the memory buffer can affect how long
Acrobat takes to perform tasks, such as opening the document, advancing to the next page, changing views, and
carrying out commands.
• Only Read The Currently Visible Pages This option is usually best when you use a screen magnifier. It improves
performance by eliminating the need for the software to process parts of the document that aren’t visible. When
Acrobat sends only the currently visible pages of a PDF to the memory buffer, the assistive technology has access to
those pages only. It cannot go to another page until the next page is visible and Acrobat has sent the page information
to the memory buffer. Therefore, if this option is selected, you must use the navigation features of Acrobat, not those
of the assistive technology, to navigate from page to page in the document. You should also set the Default Page Layout
option in preferences to Single Page if you choose to have Acrobat send only the currently visible pages to the assistive
technology. Because Acrobat sends page information about all visible pages, the assistive technology receives
information about pages that may be only partially visible (such as the bottom of one page or the top of the next), as
well as those pages that are completely visible. If you use a page display setting other than Single Page, such as
Continuous, and then you display the next page, the technology may not correctly track which portion of a previous