PDFlib 8 Windows COM/.NET Tutorial

Acrobat’s Accessibility Checker. Acrobat’s accessibility checker can be used to determine
the suitability of Tagged PDF documents for consumption with assisting technology
such as a screenreader. Some hints:
> Most importantly, all page content should be tagged. Content outside the tag structure
will not be accessible, and will therefore be flagged by Acrobat’s accessibility
checker.
> In order to make form fields accessible, use the tooltip option of create_field( ) and
create_fieldgroup( ).
> If a page contains annotations, Acrobat reports that »tab order may be inconsistent
with the structure order«.
> The Alt tag is ignored for Figure tags.
Export to other formats with Acrobat. Tagged PDF can significantly improve the result
of saving PDF documents in formats such as XML or RTF with Acrobat.
> Acrobat 8/9: If an imported PDF page has the Form tag, the text provided with the
ActualText option will be exported to other formats in Acrobat, while the text provided
with the Alt tag will be ignored. However, the Read Aloud feature works for both
options.
> Acrobat X extracts the content «as is«: the Alt and ActualText options are ignored, as
well as Private and NonStruct tags.
> Acrobat 8/9 only: the contents of a NonStruct tag will not be exported to HTML 4.01
CSS 1.0 (but it will be used for HTML 3.2 export).
> Alternate text should be supplied for ILSEs (such as Code, Quote, or Reference). If the
Alt option is used, Read Aloud will read the provided text, but the real content will be
exported to other formats. If the ActualText option is used, the provided text will be
used both for reading and exporting.
Acrobat’s Read Aloud Feature. Tagged PDF will enhance Acrobat’s capability to read
text aloud.
> When supplying Alt or ActualText it is useful to include a space character at the beginning.
This allows the Read Aloud feature to distinguish the text from the preceding
sentence. For the same reason, including a period character ’.’ at the end may also be
useful. Otherwise Read Aloud will try to read the last word of the preceding sentence
in combination with the first word of the alternate text.
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