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This sample chapter is for review purposes only. Copyright © The Goodheart-Willcox Co., Inc. All rights reserved. 126 Graphic Communications Chapter 7 Digital Prepress 127 Important Terms and the Joint Photographic Experts Group (JPEG), have created standards by which digital media and additive color page grid equipment must operate in order to be compatible. aliasing palette Due to the amount of information and the vast number antialiasing pasteboard of products available, this chapter covers general autotracing platform information that applies to digital prepress operations. Chapter Bezier curve PostScript bitmapped images PostScript printer bits typeface fi le Digital Basics byte PostScript Type 1 font color management system prefl ighting The desktop computer has become the focal (CMS) print engine point of job creation and assembly of text and images comparison proofi ng proof into page layouts within the graphic communications context-sensitive menu proofreading industry. The computer and associated devices, in cross-platform proofreader’s marks conjunction with the specialized graphics programs, design axes RAID are components in the digital prepress system, 7 dialog box random-access Figure 7-1. digital prepress system memory (RAM) A computer uses a binary system to process and dot pitch raster image processor store information in digital form. This means that the drop-down menus (RIP) computer recognizes only two numbers or digits: 1 font set selective compression and 0. These digits represent two states, on (1) and gigabyte separation plates off (0). The individual 1s and 0s are called bits, or graphical user interface (GUI) smoothing binary digits, and can be combined into groups of Digital Prepress hardware soft proofs eight digits to create a binary word, or byte. Since ink-jet proofs software there are 256 possible combinations of 1s and 0s interpreter style sheet in an eight-digit byte (from 11111111 to 00000000), Job Defi nition Format (JDF) subtractive color a special code was devised to assign a specifi c Learning Objectives lossless compression formation meaning to each combination. After studying this chapter, you will be able to: algorithms suitcase fi le • Identify different computer platforms. lossy compression template algorithms text fi lter • Explain the characteristics of different types of megabyte toner storage devices. modem two-person proofi ng • Differentiate between various output devices. open press interface (OPI) vector fonts • Explain the processes used in text and graphics system vector images preparation. output device WYSIWYG page description language WYSIWYP • Summarize the features of page composition (PDL) programs. • Identify the techniques used in creating digital design fi les. Digital systems have penetrated every stage of • Explain the proofreading process. the printing process: from formatting the author’s manuscript, to platemaking and running the press. • Explain the prefl ighting process. Maintaining a smooth workfl ow requires the consistency Figure 7-1. Using word processors on a computer • Compare types of production proofs. of digital data throughout the production process. is the most common method of composing text for printed documents. A computer is also used for • Explain digital prepress workfl ow. Sustaining consistency, as well as compatibility, requires that everyone involved in the production process have creating page layouts in page composition software. an understanding of digital media. In a perfect world, every piece of digital equipment, digital prepress system: A computer-centered process as well as every computer program and fi le produced, that consists of preparing content, composing pages, and would be compatible. Unfortunately, this is not the outputting the fi nished fi le. case. For this reason, many organizations, such as bit: Binary digit. The basic unit of digital information. the American National Standards Institute (ANSI), byte: A binary word, or group of eight individual 1s and 0s. the International Standards Organization (ISO), 128 Graphic Communications Chapter 7 Digital Prepress 129 The American Standard Code for Information software have made this platform a strong competitor Hard Drive Interchange (ASCII) provides a way to digitally store to the Macintosh® for DTP applications. Both external and internal hard drives are common and process letters, numbers, punctuation marks, ® today, Figure 7-4. A hard drive contains one or more and symbols. When the letter C is pressed on a UNIX rigid, non-removable aluminum disks coated with a keyboard, for example, it is converted to a specifi c ® UNIX is a computer operating system that was magnetic material. When the computer is operating, combination of 1s and 0s. Different combinations are developed in 1969 by a group of AT&T employees at the drive motor spins the disk and a read/write head assigned for the capital and lowercase forms of each Bell Labs. During the late 1970s and early 1980s, the moves over the disk surface, which contains densely letter. Once in digital form, the information can be ® infl uence of the UNIX system within academic circles packed magnetic tracks. The head is used to write, processed by the computer’s circuits and stored as led to large-scale adoption of the operating system by or magnetize, information to portions of the tracks as digital or magnetic charges. commercial startups, the most notable of which is Sun they spin past the head. The head can also read, or Regardless of size or complexity, a computer ® Microsystems, Inc. The Macintosh OS X operating play back, previously stored information. system has three major functions: input, processing, ® system is a UNIX -based operating system. The amount of information that can be stored on and output, Figure 7-2. Computer systems also have ® Today, UNIX -like operating systems are a hard drive has increased steadily from fewer than some means of storing information, either within ® Figure 7-3. Desktop publishing allows graphic commonly found, in addition to certifi ed UNIX 10 megabytes to capacities measured in gigabytes. the system, in a portable form, or both. There are a ® ® designers to create and edit both text and art. systems. Linux is a UNIX -like computer operating Almost unlimited storage capacity is available with number of different methods and devices used for system and one of the most common open-source a confi guration known as a RAID (Redundant Array input, storage, and output. They are described in the operating systems. An open-source operating system of Independent Disks), which connects a number of following sections. Some fi le formats and devices are cross- is a computer system that has had part of the source platform, which means they can operate on or be high-capacity hard drives together, Figure 7-5. The code released so third parties can develop programs. connected drives act like a single, huge hard drive, used with different platforms. For example, a cross- Being a free, open-source system, the Linux® source Computer Platforms platform word processing program allows users which is an advantage when managing extremely code can be modifi ed, used, and redistributed by large fi les involving graphics and text. Virtually all The platform of a digital prepress system is the to create and modify documents using different anyone. It is used as an operating system for a wide computer system hardware used to operate various operating systems, if necessary. Ideally, all computer digital prepress systems have an internal hard drive. variety of computer hardware, including desktop The single most critical occurrence for a hard programs. Computer platforms include the elements systems involved in creating and producing a computers like the Macintosh® OS X, supercomputers, necessary to create, assemble, and output data document or project would use the same operating drive is when it becomes inoperable, or crashes. video game systems, and embedded devices, such The adage of “It isn’t if your hard drive is going to in the fi nished pages, Figure 7-3. Major computer platform. When this is not possible, using cross- as mobile phones and routers. platforms are PC (based on the Microsoft® Windows® platform applications and devices reduces errors crash, it’s when your hard drive is going to crash” operating system and the Intel® chip architecture), due to fi le conversion and makes the entire process should be taken very seriously. Optimizing the drive Apple® Macintosh®, and UNIX®. Once the platform more effi cient. Memory Types for operational effi ciency and regularly backing up the data should be part of standard operating is defi ned, software developers design and install In addition to having a computer system capable ® procedures. corresponding software applications. Software Macintosh of running programs, there must be some means is a computer program that initiates a specifi c The Macintosh® computer was introduced in 1984 of storing and transmitting data. Every computer function of the computer. Types of software include and quickly became popular because of its ease of system is equipped with a certain amount of physical word processing, page composition, and graphics use and ability to generate high-quality graphic memory, usually referred to as random-access programs. images. The Macintosh® system was designed memory (RAM). RAM is the short-term memory platform: The computer system that is used to operate around the concept of a graphical user interface the computer uses to store information in process. software. The platform defi nes the standard around which a (GUI), which allowed for easy-to-understand, on- Systems can be updated and memory capabilities system can be developed. Processing screen graphic representations of computing tasks. can be increased to enhance computing effi ciency. hardware: A computer and its associated devices. Output At that time, competing platforms were based on the Because most page composition fi les are very software: Computer programs that initiate and accomplish more diffi cult method of typing commands to perform large, there are many types of storage devices available various computer-based tasks.
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