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                                                   1048
          APPENDIX F                                                              Linearized PDF



    F.3.4 Generic Hint Tables

          Certain categories of objects are associated with the document as a whole rather
          than with individual pages (see Section F.2.9, “Other Objects (Part 9)”), and it is
          sometimes useful to provide hints for accessing those objects efficiently. For each
          category of hints, there is a separate entry in the primary hint stream giving the
          starting position of the table within the stream (see Section F.2.5, “Hint Streams
          (Parts 5 and 10)”).

          Such hints may be represented by a generic hint table, which describes a single
          group of objects that are located together in the PDF file. The entries in this table
          are listed in Table F.9. This representation is used for the following hint tables, if
          needed:

          • Outline hint table
          • Thread information hint table
          • Named destination hint table
          • Information dictionary hint table
          • Page label hint table
          Generic hint tables may also be useful for application-specific objects accessed by
          plug-in extensions. It is considerably more convenient for a plug-in to use the ge-
          neric hint representation than to specify custom hints.

                                      TABLE F.9 Generic hint table
ITEM          SIZE (BITS)       DESCRIPTION

1             32                The object number of the first object in the group.

2             32                The location of the first object in the group.

3             32                The number of objects in the group.

4             32                The length of the object group in bytes.


    F.3.5 Extended Generic Hint Tables

          An extended generic hint table begins with the same entries as in a generic hint
          table, followed by three additional entries, as shown in Table F.10. This table is

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