9
What’s New
This section provides an overview of the extensions to the PDF specification.
Adobe BaseVersion 1.7 and ExtensionLevel 3
The Adobe PDF extensions for BaseVersion 1.7 and Adobe ExtensionLevel 3 extend the PDF specification
with the features introduced here. Each feature description references the format changes that make the
feature possible.
Extension identification
Extension identification lets companies and other entities identify their own extensions relative to a base
version of PDF. Additionally, the convention identifies extension levels relative to that base version. (See
“TABLE 3.25 Entries in the catalog dictionary” on page 23
.)
Bates numbering page artifact
The Bates number page artifact lets PDF processors override the starting point for the Bates Numbering
for the pages in a PDF document. This feature ensures consistent Bates Numbering for pages that were
extracted from another PDF document. (See
“TABLE 10.17 Property list entries for artifacts” on page 100
.)
Features for Architecture, Engineering and Construction
Enforced viewer preferences
Enforced viewer preferences instruct a conforming reader that the user cannot override viewer settings
specified in PDF documents. Examples of such viewer preferences are default print scaling value and
number of copies.
In one application of this feature, consider a PDF document that contains architectural or engineering
drawings. If the scaling of such a document were changed for printing, the document may be
compromised. This feature can be used to enforce default print scaling, which ensures that the document
is printed with the default scaling. (See
“Table 8.1 Entries in a viewer preferences dictionary” on page 28
.)
Persistence of 3D measurements and markup
3D measurement and markup data can now be stored in the PDF file, facilitating the communication of 3D
shape information between users. The introduction of 3D annotations to the PDF format lets users create
views of 3D data to illustrate important 3D features. The addition of 3D measurement definitions also lets
users more accurately describe 3D data. This capability is a key step in using a PDF document as the
primary mechanism for transferring information in manufacturing and AEC workflows. (See
“9.5.6
Persistence of 3D Measurements and Markups” on page 59
.)
