CHAPTER 10
842
Document Interchange
•
The
Web Capture
plug-in extension (Section 10.9), which creates PDF files
from Internet-based or locally resident HTML, PDF, GIF, JPEG, and ASCII text
files
•
Facilities supporting prepress production workflows (Section 10.10), such as
the specification of
page boundaries
and the generation of
printer’s marks, color
separations, output intents, traps,
and low-resolution
proxies
for high-resolution
images
10.1 Procedure Sets
The PDF operators used in content streams are grouped into categories of related
operators called
procedure sets
(see Table 10.1). Each procedure set corresponds
to a named resource containing the implementations of the operators in that pro-
cedure set. The
ProcSet
entry in a content stream’s resource dictionary (see Sec-
procedure sets used in that content stream. These procedure sets are used only
when the content stream is printed to a PostScript output device. The names
identify PostScript procedure sets that must be sent to the device to interpret the
PDF operators in the content stream. Each element of this array must be one of
the predefined names shown in Table 10.1. (See implementation note 159 in
TABLE 10.1 Predefined procedure sets
NAME
CATEGORY OF OPERATORS
PDF
Text
ImageB
ImageC
ImageI
Painting and graphics state
Text
Grayscale images or image masks
Color images
Indexed (color-table) images
Note:
Beginning with PDF 1.4, this feature is considered obsolete. For compatibility
with existing consumer applications, PDF producer applications should continue to
specify procedure sets (preferably, all of those listed in Table 10.1 unless it is known
that fewer are needed). However, consumer applications should not depend on the
correctness of this information.