An Overview of Digital Printing Systems - Control of Color Imaging Systems: Analysis and Design - page 2

with offset printing. Understanding some of the key steps involved in the printing
and publishing work ow can shed some light on the complexity of the system.

ows (various steps required all the way from receiving the orders in a print
shop to the production of a job in

Work

finished form) are generally unique to each print

shop. The typical work ows used in both areas of printing (digital and offset) can be

divided into three main components: (1) business management, (2) output produc-
tion, and (3) process management

= supporting functions (see Figure 1.1 for a block

diagram view of the work ow process). It includes not just the actual production

steps, but all the necessary supporting tasks like billing, archival, etc.

1.2.1 B USINESS M ANAGEMENT
Business management tasks (the top portion of Figure 1.1) involve taking orders from
customers, and assigning job-tracking numbers for monitoring purposes. Order infor-
mation may include artwork, text, illustrations, design

=

layout, variable information
rules, demographic data, etc. Pricing is estimated for the order and compared with the
actual cost of running the job. Aspects related to handling the shipment of the

finished
job, archiving, and billing are an integral part of business management functions.
Customers and sales service representatives are involved at the order-taking stage. A

project manager handles the job tracking and billing issues.

=

1.2.2 O UTPUT P RODUCTION
After the order taking step, customer data flow into the output production stage (the

middle portion of Figure 1.1). This category can be further divided into creative,
prepress, print (press),

ll stages. For high-volume, single-shipment,
sheet-oriented documents, offset presses are used. Customer data is directly sent to
the prepress area. For low-volume, multishipment, and variable information documents,
the customer data is processed in the creative stage before sending it to prepress. In the
creative stage, concepts and drawings are developed; documents are designed by
assembling the content using various layout tools. Image capture from scanner or
other document input devices are done in this stage.
Electronic documents are then sent to the prepress area for further processing and
assembly. Since documents could be of various formats and color spaces
(

finish, and ful

), proper design choices are required before converting the documents
to the language required by the raster image processor (RIP), which converts a
document

RGB=CMYK

s strings of character codes to pixels. Generally speaking, the prepress
stage (see Figure 1.2) encompasses all the steps involved in creating a digital
electronic master. In a typical prepress system, multiple workstations are networked
together to serve as the publishing desktop for generating, editing, managing,
manipulating, and integrating multimedia content. Scanners are usually connected
to the workstations to convert hardcopy documents (photos on

'

film, paper handouts,
etc.) to electronic form by utilizing a variety of image scanning software packages.
Similarly, digital still and

= or video cameras offer the user the ability to capture single

snapshots and = or video imagery. Once captured, the images — stored electronically in