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                                                     1049
            SECTION F.3                                                                    Hint Tables



            used to provide hints for accessing objects that reference shared objects. As of
            PDF 1.5, the following hint tables, if needed, use the extended generic format:

            • Interactive form hint table
            • Logical structure hint table
            • Renditions name tree hint table
              Note: Embedded file streams should not be referred to by this hint table, even if
              they are reachable from nodes in the renditions name tree; instead they should use
              the hint table described in Section F.3.6, “Embedded File Stream Hint Tables.”

                                  TABLE F.10 Extended 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.

5      32                         The number of shared object references.

6      16                         The number of bits needed to represent the numerically greatest shared ob-
                                  ject identifier used by the objects in the group.

7…     See Table F.3, item 11     Starting with item 7, each of the remaining items in this table is a shared ob-
                                  ject identifier—that is, an index into the shared object hint table (described in
                                  Section F.3.2, “Shared Object Hint Table”).


    F.3.6 Embedded File Stream Hint Tables

            The embedded file streams hint table allows a viewer application to locate all byte
            ranges of a PDF file needed to access its embedded file streams. An embedded file
            stream may be grouped with other objects that it references; all objects in such a
            group must have adjacent object numbers. (A group may contain no objects at all
            if it contains shared object references.)

            This hint table has a header section (see Table F.11), which has general informa-
            tion about the embedded file stream groups. The header section is followed by
            the entries in Table F.12. Each of the items in Table F.12 is repeated for each em-

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