K Mean Black

• Name: B.Tech 4rd Year
• Branch: B.Tech Printing Technology 7th Sem
• Published: Oct. 2, 2025

Computer Graphic in Printing

UNIT-1

Overview of Computer Graphics

Computer Graphics is the art and science of generating visual images using computers. It is widely used in printing, packaging design, publishing, animation, gaming, and industrial design.

Types of Computer Graphics

1. Interactive Graphics

• The user can interact with the system to modify the graphics in real-time.
• Example: Graphic design software like Adobe Illustrator, CAD applications, packaging mockups.
• Features:
  • Real-time editing of objects.
  • User input via mouse, keyboard, or stylus.
  • Dynamic response to commands.

2. Passive Graphics (Non-interactive graphics)

• Graphics are predefined and cannot be modified by the user in real-time.
• Example: Images in a slideshow, printed brochures, or video playback.
• Features:
  • Output is static.
  • No interaction or manipulation by user.

 

Advantages of Interactive Graphics

1. Real-time Manipulation – Allows designers to instantly see changes.

2. Improved Design Accuracy – Easy corrections and precise measurements.

3. Better Visualization – 3D previews of packaging, product mockups, or illustrations.

4. Faster Decision Making – Immediate feedback helps speed up design approvals.

5. Enhanced Learning & Training – Simulations in printing, packaging, and industrial design.

 

Introduction to 2-D and 3-D Graphics

A) 2-D Graphics (Two-Dimensional)

• Represent objects in height and width (x, y coordinates).
• Commonly used for: logos, labels, book covers, flat packaging design.
• Features:
  • Shapes: lines, circles, rectangles, polygons.
  • Text and annotations.
  • Image manipulation (scaling, rotation, translation).

B) 3-D Graphics (Three-Dimensional)

• Represent objects in height, width, and depth (x, y, z coordinates).
• Used for product mockups, rigid packaging prototypes, or architectural visualizations.
• Features:
  • Perspective views, shading, lighting, textures.
  • 3D modeling software: Blender, AutoCAD 3D, 3ds Max.
  • Allows rotation, zooming, and realistic rendering.

 

Display Devices

Display devices are hardware used to visualize graphics on a screen.

A) CRT (Cathode Ray Tube)

• Traditional display using electron beams to excite phosphor on the screen.
• Types:

1. Refresh CRT / Random-Scan Monitor

• Vector displays: draw images as lines connecting points.
• Good for line drawings, engineering diagrams, CAD.
• Limited in color and complex images.

2. Raster-Scan Monitor

• Display composed of pixels arranged in a grid.
• Used for images, photographs, and complex designs.

B) Color CRT Monitors

• CRT monitors capable of displaying millions of colors using RGB phosphors.
• Commonly used before LCD and LED monitors became mainstream.

C) DVST (Direct View Storage Tube)

• Displays images without refreshing for a long time.
• Mostly used in specialized industrial applications.
• Advantage: minimal flicker, suitable for static line graphics.

D) Plasma-Panel Displays

• Flat-panel display using small cells of electrically charged plasma.
• Advantages: large screens, high brightness, good color reproduction.
• Used in digital signage and presentation boards.

E) LED and LCD Monitors

• LED (Light Emitting Diode) – Backlight for LCD screens; energy-efficient, high brightness.
• LCD (Liquid Crystal Display) – Uses liquid crystals to block or transmit light.
• Advantages:
  • Slim design, low power consumption.
  • High-resolution graphics suitable for 2D/3D visualization.
• Widely used in graphic design studios, packaging design, and CAD workstations.

 

Hard Copy Devices

• Devices used to produce physical copies of digital graphics.
• Examples:

1. Printers – Inkjet, Laser, Thermal, 3D Printers.

2. Plotters – Used for large-scale designs, banners, engineering drawings.

• Essential in printing & packaging industry for prototypes, labels, and final products.

 

UNIT-2

Language and File Formats

In graphic arts, publishing, and printing, document processing languages and file formats are essential for creating, editing, storing, and transmitting digital content. The choice of language/format affects compatibility, quality, and workflow efficiency.

 

A) Document Processing Language (DPL)

Definition:
A Document Processing Language is a type of programming or markup language used to describe the layout, content, and formatting of documents so that they can be printed, displayed, or shared digitally.

Purpose:

• To define text, images, tables, and page layout in a standardized way.
• To ensure device independence → the same document can be printed or displayed across different printers or screens.
• To allow automation of document generation in publishing, printing, and packaging.

 

Common Document Processing Languages

Language	Description	Usage in Printing/Publishing
PostScript (PS)	Page description language developed by Adobe. Describes text, graphics, and layout using commands.	Widely used in high-quality printing; input for printers and RIPs.
PDF (Portable Document Format)	Based on PostScript; preserves fonts, images, and layout.	Standard for exchanging print-ready documents, books, brochures, packaging dielines.
TeX / LaTeX	Markup language for scientific and technical documents; precise control over layout and fonts.	Used in technical publishing, journals, and books.
XML (Extensible Markup Language)	Flexible markup language for structured data.	Document automation, digital publishing, content management systems (CMS).
HTML / XHTML	Hypertext markup for web documents.	Online publications, e-books, digital catalogs, interactive packaging content.

 

B) Document File Formats

Purpose: File formats define how digital data (text, images, vector graphics) is stored for processing, editing, or printing.

File Format	Type	Features / Usage
.doc / .docx	Word processor	Editable text, basic layout; used for manuscripts, letters, text content.
.pdf	Portable Document	Print-ready, preserves fonts & layout, widely used in publishing & packaging proofs.
.eps	Encapsulated PostScript	Vector graphics; scalable for logos, illustrations; compatible with professional printers.
.ai	Adobe Illustrator	Vector-based design; used for packaging artwork, illustrations, labels.
.indd	Adobe InDesign	Page layout software; multi-page documents, magazines, brochures.
.tiff / .png / .jpg	Image formats	TIFF → high-quality printing, PNG → web & transparent graphics, JPEG → photos.
.svg	Scalable Vector Graphics	Vector for web or digital packaging; scalable without quality loss.

 

C) Key Points on DPL & Formats

1. Device Independence: DPLs like PostScript ensure consistent output on any printer.

2. Workflow Integration: PDF, EPS, AI files can move seamlessly between designer → prepress → printer.

3. Editing vs Final Output: Word docs are editable; PDF/EPS are mostly final output formats.

4. Vector vs Raster: Vector (EPS, AI, SVG) → scalable without quality loss. Raster (JPEG, PNG, TIFF) → pixel-based; quality depends on resolution.

 

POST SCRIPT LANGUAGE

RIP (raster image processor): A RIP operate by transforming the font-end instruction form the HOST DTP/EPS system, which are stored in post script language.

The post script language consist of 300 command that instruct the programme to move to certain point, draw lines, fill box. Select type. In an application programme files is create and stored in internal format when these file is converted in to post script and it is converted PS code.

The save file is send to output device, where the interpreter execute the code and translate the page into raster image in the coordinate system of the output device.

Create a list of all the object on a page, known as a ‘display list’.

The raster image sent to the marking engine which produces it into film or paper.

 

Two types of RIP:

1. Hardware and software (RIP)

a. Software: the process of converting the received image data into bitmap of device pixel values is known as RIP.

Each RIP has limit on the overall size of each single graphic. It can handle at any-one time with just below A3, for example being the maximum some RIP’s can handle. Adobe, the originate and developer of post script has issued licenses for RIP design which continue to improve to take account of development such as postscript levels 2 & 3.

Most forms of powerful output device are controlled by a RIP from, for example, color copiers transformed into color printers to image setters and CTP systems. RIP are designed to run apple mac, PC and UNIX platforms. General purpose RIP’s driving a wide range of output devices.

The MGI ‘JETSTREAM’ RIP has facility to support color copiers, electrostatic and inkjet printers, as well as image setters on the apple mac, PC or UNIX platform.

Major process companies such as linotype-hell (now Heidelberg prepress) and Agfa has developed RIP to drive their specific range of image setter.

1. Linotype-hell developed the ‘DELTARIP’ to drive some of image setter. It consist of three parts, delta software, delta workstation and delta tower.

Delta software is drives the A3+ Quas or B2 Herkules and dry-setter image setter.

Delta workstation is based on a PC running Windows NT.

The delta tower looks after the screening requirement.

 

2. Afga has developed the ‘COBRA’ software RIP run on a UNIX platform SPARC workstation which is capable of driving image setters and other input and output devices simultaneously.

Electronics for imaging (EPI) are well known in the industry for their fiery RIP’s converting color copier into color printers, the range has to cover large format digital printing.

Proprietary/Delicated RIP’s developed by harlequin company and produced its own postscript interpreters.

Rich RIP’s which are very popular in high-end workflows driving image setters, plate setter, digital proofing system and digital presses.

Function of RIP:

1. Trapping

2. Imposition

3. Color conversion to CMYK

4. Half-toning and dot gain compensation

5. OPI image storage.

 

1. Vector Graphics

Definition:

Vector graphics represent images using mathematical formulas — points, lines, curves, and polygons.

Characteristics:

• Resolution-independent: Can be scaled to any size without losing quality.
• File size: Usually smaller than high-resolution bitmap images for the same image.
• Editable: Easy to change shapes, colors, and strokes.
• Ideal for: Logos, icons, line art, packaging designs, typography.

File Formats:

• AI (Adobe Illustrator), EPS (Encapsulated PostScript), SVG (Scalable Vector Graphics), PDF (vector content).

 

2. Bitmap (Raster) Images

Definition:

Bitmap images are composed of a grid of pixels, each having a specific color.

Characteristics:

• Resolution-dependent: Scaling up reduces quality (pixelation).
• File size: Can be large if resolution is high.
• Editing: Editing is less flexible; modifying shapes/colors can degrade quality.
• Ideal for: Photographs, scanned images, textures.

File Formats:

• JPEG / JPG, PNG, GIF, TIFF / TIF, BMP.

 

3. Life-Size Images

Definition:

• Life-size images are designed to appear at actual size when printed or displayed.

Applications:

• Life-size posters, mannequins in advertising, packaging dielines, signage.

Considerations:

1. Resolution: High DPI (dots per inch) is needed for print quality (usually 300 DPI or more).

2. Vector vs Bitmap:

• Vector graphics → ideal for life-size images like banners, posters with large text or logos.
• Bitmap images → need high-resolution scans to avoid pixelation at large sizes.

 

4. Image Compression

Purpose:

• Reduce file size for faster storage, transfer, and web usage without losing significant quality.

Types of Compression:

1. Lossless Compression:

• No data loss; original image can be perfectly restored.
• Examples: PNG, TIFF, GIF.
• Ideal for logos, line art, illustrations.

2. Lossy Compression:

• Some data is discarded to reduce file size; slight quality loss.
• Examples: JPEG / JPG.
• Ideal for photographs, web images, online catalogs.

Advantages:

• Faster loading for websites.
• Saves storage and bandwidth.
• Efficient for email attachments and cloud sharing.

 

5. Linking Objects to URLs for Web Pages

Definition:

• Hyperlinking is the process of attaching a URL (web address) to an object (text, image, or button) so that clicking it opens a web page.

Applications in Graphic Arts / Web Design:

• Interactive online catalogs.
• Clickable packaging mockups.
• Infographics with external references.

Implementation:

1. HTML Example:

<a href="https://www.example.com">

   <img src="packaging-design.png" alt="Packaging Design">

</a>

• The image becomes clickable and opens the URL.

2. Software Tools:

• Adobe Illustrator / InDesign → Export interactive PDF with clickable links.
• Canva / Figma → Link objects in interactive prototypes or digital marketing materials.

Benefits:

• Makes digital publications interactive.
• Enhances user engagement for online marketing or e-commerce.
• Can connect print design mockups to online resources via QR codes.

 

6. Portable Document Format (PDF)

Definition:

• PDF is a platform-independent file format developed by Adobe that preserves fonts, images, graphics, and layout.
• Commonly used for print-ready documents and digital publishing.

Key Features:

• Device-independent output → looks the same on all screens/printers.
• Supports vector & raster graphics, text, hyperlinks, and metadata.
• Can be interactive (forms, buttons, hyperlinks).

 

7. Print Document Format (PDF/X)

• PDF/X is a special subset of PDF standardized for printing.
• Ensures color management, fonts embedding, and correct trapping.
• Avoids errors in prepress workflow.
• Used in: Commercial printing, packaging, magazine and book publishing.

 

8. PDF Workflow Systems

Definition:

• Workflow systems that use PDF as the central format for prepress, proofing, approval, and printing.

Advantages:

• Standardized communication between designers, prepress, and printers.
• Easier proofing and review → online annotations.
• Compatible with RIP (Raster Image Processors) and color management systems.

Workflow Example:

1. Designer creates layout → exports PDF/X.

2. Prepress checks PDF for errors (fonts, images, colors).

3. RIP converts PDF pages to raster for printing.

4. PDF sent to press → printed output matches digital proof.

 

9. Print Job Ticket Format (PJTF)

Definition:

• PJTF is a digital or physical document that describes the specifications of a print job.
• Used to communicate requirements from client/designers to the printer.

Contents of PJTF:

• Job name and reference number
• Number of copies / pages
• Paper type and size
• Color requirements (CMYK, Pantone)
• Finishing instructions (lamination, binding, die-cut)
• Delivery schedule

 

10. Raster Image Processing (RIP)

Definition:

• RIP converts vector graphics and text into raster (bitmap) images for printing.

Purpose:

• Printers can only print dots (halftones), so vector and text must be converted to pixels.
• Supports color separation and halftoning for CMYK presses.

Workflow:

1. PDF or EPS input → RIP software
2. Conversion into raster images at printer resolution
3. Output to plates (offset) or digital press

 

11. Linking & Electronic Dot Generator

A) Linking

• Linking objects means connecting external resources (images, text, logos) to a document rather than embedding them.
• Advantages:
  • Smaller file size
  • Easy to update linked resources without editing the main file

B) Electronic Dot Generator (EDG)

• Used in prepress for printing halftones.
• Converts continuous-tone images into dots of varying sizes for printing (halftoning).
• Essential for offset and digital printing to reproduce photos accurately.

 

12. Publishing Software

A) PageMaker

• Adobe PageMaker: Desktop publishing software for creating brochures, magazines, newsletters, and books.
• Features:
  • Multi-page layout
  • Master pages for consistent design
  • Supports text, vector, and raster images

B) CorelDraw

• Vector graphics software used for illustrations, logos, packaging, signage, and large-format printing.
• Features:
  • Vector drawing tools (lines, curves, shapes)
  • Color management
  • Export to EPS, PDF, SVG, and print-ready formats

C) Other Popular Publishing/Design Software

• Adobe InDesign → modern replacement for PageMaker for multi-page layouts
• Adobe Illustrator → vector graphics for logos, packaging, and illustrations
• QuarkXPress → high-end publishing

 

UNIT-3

FILE FORMAT:

1. GIF: (graphic interchange format) it format on the web and storing picture like-live drawing and simple cartoon.

2. JPEG: (joint photographer’s expert group) it stores full color information 24 bit/ pixel and much small than GIF’s.

3. TIFF: bitmap files (tagged image file format) it storing bitmap and does not oriented image or text.

It has different level based on no. of color or grey.

It transport for raster image and desktop publishing format.

4. PICT: (macintosh format) it based on quick draw, the mac’s native graphic language object and bitmap can be write white, black, cyan, magenta, yellow, red, green, and blue can hold resolution greater ’72 dpi’.

It is readily imported but poorly supported by publishing application.

5. DCS: (desktop color separation) DCS is a file format that creates four color separation by saving image as a set of ‘EPS’ file. It is used to exchange color data between retouching, separation and page layout.

The complete preview image is store in one file. The individual ‘CMYK’ color plate are stored in separate file. It advantage editing program easily support.

6. PDF: (portable document file) it used to represent a document of the application software, hardware. The PDF writer available both in MAC and WINDOW. It useful for interactive viewing.

7. Post script: a method to describe typographic as vector or outlines at same time introduce PS language. It used for raster based printer and in file include all type and graphic information.

8. EPS: (encapsulated post script) in the ‘EPS’ file special function like transfer curve, screen rulling and separation information embedded in the file that cannot be changed once it leave the creator of the file.

EPS used for storing object oriented and bitmapped software and it has two sub-type-ASCII (text) and binary (hexadecimal).

ASCII format contain two version one is high resolution ‘PS’ description for printing on ‘PS’ device and second is low bitmapped PICT preview and it can be display on the monitor without PS

 

UNIT-4

Interactive Graphics

Definition:

• Interactive graphics allow real-time communication between the user and computer graphics system.
• Users can modify, manipulate, or control graphical objects dynamically.

Applications:

• Packaging mockups, book layouts, CAD designs, digital illustrations.

 

Concept of Positioning and Pointing

• Positioning: Determining the exact location of a graphical object on the screen.
• Pointing: Selecting or indicating objects in the graphics workspace.

Purpose:

• Ensures precise placement of logos, text, images in design.
• Critical for CAD layouts, packaging dielines, and UI/UX design.

Examples:

• Clicking a point to place a text box.
• Dragging an object to a specific position on the artboard.

 

Interactive Graphic Devices

These are hardware devices that allow users to interact with graphical objects:

Device	Description	Use
Keyboard	Traditional input device	Shortcut commands, numeric input, text editing
Touch Panel / Touch Screen	Detects finger or stylus input	Direct selection, design manipulation, on-screen annotation
Light Pen	Detects light from CRT screens	Pointing & selecting objects (used in older CAD systems)
Graphic Tablets	Pressure-sensitive pen on tablet	Drawing, sketching, vector illustrations
Joystick	Manual control stick	Moving cursor or rotating objects in 3D graphics
Mouse	Pointing device	Selection, dragging, drawing, menu navigation
Voice System	Voice commands for graphics control	Hands-free operation, accessibility features

 

Interactive Graphical Techniques

A) Basic Positioning Methods

• Using coordinates (x, y, z) to place objects precisely.

B) Constraints

• Limit object movement according to rules, e.g., straight line, fixed distance.

C) Grids

• Grid lines help align and snap objects, useful in packaging layout and page design.

D) Gravity Field

• Objects are “pulled” toward specific points for alignment or connection (like snapping to guides).

E) Rubber-Band Methods

• Visual feedback technique: stretching a line or shape while dragging before final placement.

F) Sketching

• Free-hand drawing with stylus/tablet to create outlines or illustrations.

G) Dragging

• Moving objects across the screen by selecting and dragging.

H) Inking and Painting

• Filling objects with colors, gradients, textures.
• Example: coloring packaging dielines, adding shading to illustrations.

 

Computer Graphic Software

Definition:

• Software used to create, manipulate, and display graphics.

Example: GKS (Graphical Kernel System)

• GKS is a standardized software library for computer graphics.

Components:

1. Primitives

• Basic graphical elements: lines, circles, polygons, text.

2. Attributes

• Properties like color, line type, fill pattern, thickness.

3. Viewport

• Defines the area of the world coordinate system displayed on screen.

4. Display Subroutines

• Functions to render objects on the output device (CRT, LCD, printer).

Applications of GKS:

• Engineering design, packaging layouts, CAD drawings.
• Acts as a foundation for higher-level graphics applications.