SECTION F.2
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Linearized PDF Document Structure
hint stream,
may be numbered out of sequence; see Section F.2.5, “Hint Streams
•
The second group consists of all remaining objects in the document, including
all pages after the first, all shared objects (objects referenced from more than
one page, not counting objects referenced from the first page), and so forth.
These objects are numbered sequentially starting at 1.
These groups of objects are indexed by exactly two cross-reference table sections,
located as shown in Example F.1. The composition of these groups is discussed in
more detail in the sections that follow (ordered by the part number as shown in
this example, with one section for parts 5 and 10). All objects have a generation
number of 0.
Beginning with PDF 1.5, PDF files may contain object streams (see Section 3.4.6,
conditions apply:
•
Certain additional objects cannot be contained in an object stream: the linear-
ization dictionary, the document catalog, and page objects.
•
Objects stored within object streams are given the highest range of object num-
bers within the main and first-page cross-reference sections.
•
For files containing object streams, hint data can specify the location and size
of the object streams only (or uncompressed objects), not the individual com-
pressed objects. Similarly, shared object references should be made to the ob-
ject stream containing a compressed object, not to the compressed object itself.
•
Cross-reference streams (Section 3.4.7, “Cross-Reference Streams”) can be
used in place of traditional cross-reference tables. The logic described in this
chapter still applies, with the appropriate syntactic changes.
Example F.1
Part 1: Header
% PDF−1 . 1
% …
Binary characters
…