SECTION 8.4
615
Anno ta tions
havior (such as displaying nothing) if an annotation’s
AS
entry designates an ap-
pearance state for which no appearance is defined in the appearance dictionary.
For convenience in managing appearance streams that are used repeatedly, the
AP
entry in a PDF document’s name dictionary (see Section 3.6.3, “Name Diction-
name strings have no standard meanings; no PDF objects refer to appearance
streams by name.
8.4.5 Annotation Types
PDF supports the standard annotation types listed in Table 8.20. The following
sections describe each of these types in detail. Plug-in extensions may add new
annotation types, and further standard types may be added in the future. (See im-
The values in the first column of Table 8.20 represent the value of the annotation
dictionary’s
Subtype
entry. The third column indicates whether the annotation is
a
markup annotation,
as described in “Markup Annotations,” below. The section
also provides more information about the value of the
Contents
entry for differ-
ent annotation types.
TABLE 8.20 Annotation types
ANNOTATION TYPE DESCRIPTION
MARKUP? DISCUSSED IN SECTION
Text
Link
FreeText
Line
Square
Circle
Polygon
Text annotation
Link annotation
(PDF 1.3)
Free text annotation
(PDF 1.3)
Line annotation
(PDF 1.3)
Square annotation
(PDF 1.3)
Circle annotation
(PDF 1.5)
Polygon annotation
(PDF 1.5)
Polyline annotation
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
PolyLine