SECTION 10.7
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Tagged PDF
Note:
The description of each of the standard attributes in this section specifies
whether their values are inheritable.
It is permissible to specify an inheritable attribute on an element for the purpose
of propagating its value to child elements, even if the attribute is not meaningful
for the parent element. Non-inheritable attributes may be specified only for ele-
ments on which they would be meaningful.
The following list shows the priority for setting attribute values. A processing ap-
plication sets an attribute’s value to the first item in the list that applies:
1. The value of the attribute specified in the element’s
A
entry, owned by one of
the export formats (such as
XML
,
HTML-3.20
,
HTML-4.01
,
OEB-1.0
,
CSS-1.00
,
CSS-2.0
, and
RTF
), if present, and if outputting to that format
2. The value of the attribute specified in the element’s
A
entry, owned by
Layout
,
PrintField
,
Table
or
List
, if present
3. The value of the attribute specified in a class map associated with the element’s
C
entry, if there is one
4. The resolved value of the parent structure element, if the attribute is inherita-
ble
5. The default value for the attribute, if there is one
Note:
The attributes
Lang
,
Alt
,
ActualText
, and
E
do not appear in attribute dictio-
naries. The rules governing their application are discussed in Section 10.8, “Accessi-
There is no semantic distinction between attributes that are specified explicitly
and ones that are inherited. Logically, the structure tree has attributes fully bound
to each element, even though some may be inherited from an ancestor element.
This is consistent with the behavior of properties (such as font characteristics)
that are not specified by structure attributes but are derived from the content.