Acrobat Extended Print Services

Adobe Systems Incorporated
September, 1996

Adobe Acrobat 3.0

The Portable Document Format (PDF) has been expanded for Adobe Acrobat version 3.0. PDF now
includes the information  necessary to work seamlessly in production printing for color and monochrome
workflows. PDF can represent all of the PostScript Level 2 imaging features, so printed integrity is
maintained when files are converted into PDF. Workflows today generally rely on the authoring application
format, or PostScript. When PDF files are used in the workflow, all printed integrity is maintained,
enabling users to take advantage of the benefits of PDF.

When high-end printing controls are specified in the PostScript output of an authoring application, they are
retained in the PDF file when converted with Acrobat Distiller  

®

 version 3.0. Once the features are

specified inside the PDF, they are output back into the PostScript stream at print time from Acrobat
Exchange (a component of Adobe Acrobat 3.0) or Acrobat Reader.

While retaining the integrity of high resolution color documents is crucial to using PDF in production
printing workflows, there are a lot of other features that can be implemented to take advantage of the power
and flexibility of PDF. For example, one may want to be able to use PDF direct to imagesetters, proofers,
and digital presses. For this to be a reality, users want control over the print features specified in the PDF
file (originally resident in the PostScript file) at any time before committing it to paper or film.

A New Acrobat Plug-in

The Acrobat Extended Print Services is a Macintosh-only Acrobat plug-in being developed by Adobe. It
extends the printing control from what is available by system-level printer drivers. The plug-in is used at
print time to specify all of the printing parameters to be used when printing the current document. It takes
advantage of PostScript Printer Description (PPD) files to enable options for the current output device, such
as the resolution and whether the device supports duplexing. Users can specify among other things, page to
media offsets and image area to page offsets, screening information, and undercolor removal/black
generation settings. The Extended Print Services can print printers marks and turn on separations in
PostScript Level 2 RIPs.

Once all of the current selections have been made, they can be saved to a file, then restored at a later time,
or for another document. One might want to maintain different settings depending on whether the output is
targeted for a proofer, imagesetter, or monochrome device. As PDF files are used more and more for
production workflows, it is crucial that control over this printing information be accessible.

All of this functionality is just the beginning. Acrobat Extended Print Services is a demonstration of the
kinds of features that can be implemented on top of PDF for the production printing market. In addition,
Adobe will provide tools and services to third party developers to enable them to extend PDF-based
workflows. Adobe will consolidate some of the core functionality common between plug-ins so that third
party developers do not have to reimplement them. The goal is to enable an environment where many
different production printing plug-ins all work together seamlessly.

Third Party Plug-ins

There are many pieces to the workflow puzzle, all of which can be implemented using PDF. There is a great
need for third party developers to build this functionality to enable production printers to take advantage of
the benefits of PDF. Here are just some of the possibilities.

• 

Imposition

◊ 

Provide access from within Acrobat to the software where templates are built

◊ 

Build custom templates in Acrobat Exchange

◊ 

Apply imposition specifications to the current PDF file, so it is used when printed

• 

OPI Management

◊ 

Enumerate the existing OPI comments

◊ 

Change the path to the high resolution images

◊ 

Resolve OPI references

• 

Color Management

◊ 

Ink mapping, all to process/revert to spot

◊ 

Edit settings for overprinting, undercolor removal, black generation, transfer functions, rendering
intent, et. al.

• 

Screening Control

◊ 

Edit settings for line screens, halftone cells, halftone phase

◊ 

FM/Stochastic screens (with dot gain and minimum spot size settings)

• 

Preflighting Tools

◊ 

Generate a report which lists the crop box size (for every page), image contents (compression, size
in bytes and pixels, color type), fonts used (embedded, subsetted, substituted), OPI references, file
size, etc.

Summary

The Acrobat Extended Print Services plug-in for Acrobat Exchange extends the user’s control over what is
printed from PDF. It is a demonstration of the functionality that can be added to PDF for use in production
workflows. Adobe is also providing a foundation upon which third parties can build vertical applications to
meet the demands of production printing for PDF. Eventually documents will be authored, immediately
output to PDF, then undergo the entire workflow process as PDF, enabled by many PDF-based applications
from many vendors.