APPENDIX I
1134
Computation of Object Digests
I.2.1 Document
When calculating a digest for the document, the following items are included, in
order:
•
The values of the following entries in the document catalog (see Table 3.25), if
present:
AA
,
Legal
; and
Perms
•
The values of the following entries in the document information dictionary
(see Table 10.2), if present:
Title
,
Author
,
Keywords
, and
Subject
•
All page objects in the document, in page order, as described in Section I.2.2,
•
All named pages specified in the
Pages
name tree, sorted by name, as described
in Section I.2.3, “Named Pages”
•
All embedded files specified in the
EmbeddedFiles
name tree, sorted by name,
as described in Section I.2.4, “Embedded Files”
I.2.2 Page Objects
For page objects (see Table 3.27), the digest includes the values of the following
entries, in order, if present. For entries listed as inheritable, their values may be
inherited from ancestor nodes in the page tree if not specified explicitly.
•
MediaBox
(inheritable)
•
CropBox
(inheritable)
•
Resources
(inheritable)
•
Contents
•
Rotate
(inheritable)
•
AA
•
Annots
. This entry consists of an array of dictionaries for annotations on the
page. They are sorted by the value of the
NM
entry; if
NM
is not present, a glo-
bally unique ID (GUID) is supplied as
NM
.
For each annotation, if it is a widget, the values added to the digest are those
specified in Section I.2.6, “Form Fields.” If it is any other type of annotation, the
values added to the digest are those specified in Section I.2.5, “Annotation Dic-