chapter 4 - graphics
TRANSCRIPT
-
8/2/2019 Chapter 4 - Graphics
1/36
Chapter 4 - Graphics
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
2/36
Chapter Objectives
Explain why graphic images are vital to multimedia
applications
List the items that should be logged in reference tographic images
Describe the role and responsibilities of the graphic
designer
Describe the different technologies that can be usedto capture and acquire digital images
Define the different types of images
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
3/36
Chapter Objectives
Explain how color resolution and image resolution
affect image quality
Define compression and compare lossy and losslesscompression
Explain the difference between bitmapped and
vector-based graphics
Describe several features of paint, draw, 3D, andimage editing programs
List and describe the different Web graphic file
formats
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
4/36
Introduction
Society is very visual
Picture really can be worth a thousand words
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
5/36
Introduction
Choosing an Image
Prepare list and description
Track vital information in an image logDescription
Source
Rights negotiated
Amount paid
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
6/36
The Graphic Designer
Create and optimize images for theWeb
Part of multimedia team
Freelance
Portfolio
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
7/36
Digitizing Images
Converting them to 0s and 1s
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
8/36
Scanners
Page/Flatbed
Page-fedOCR Software
Slide
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
9/36
Scanning Hints
Set resolution to 72 ppi
Work from an original
Do not increase resolution after ithas been lowered
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
10/36
Digital Cameras
Require no film
Store images in memory (flash RAM)Connect directly to the computer
Range in price, quality and features
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
11/36
Snapping Photographs
Take lots of photos
Shoot from a variety of angles
Shoot people in indirect light
Shoot in the morning/evening when
light is filteredTry shooting objects both indoorsand outdoors
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
12/36
Digital Video Cameras
Capture both still and moving images
Range in price, quality, and features
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
13/36
Photo CD
Service bureau
High quality
Inexpensive
Convenient
Near-permanent storage
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
14/36
Stock Photography
Commercial Image providers/Stockphotography houses
TipsFile should be Web ready
Graphic should be size and resolution
appropriate to Web page
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
15/36
Clip Art
Available with software, on CD andWeb
Must be appropriate and high quality
Can look amateurish
Public domain v. copyrightRead licensing agreements carefully
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
16/36
Original Artwork
Draw, paint, image editing software learning curve
Dont have to worry about copyright orlicensing agreements
Digitizing or Graphics tablet stylus
Spreadsheet software charts/graphs
Mapping software vector-based
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
17/36
Types of Images
Line art flat colors
Continuous tone photographs
Grayscale 256 levels of gray
Two-dimensional
Three-dimensionalHypergraphics
Image Maps
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
18/36
Image Quality
Many factors impact image quality
Some are dependent on equipmentNo control over differences in gammasettings, dot pitch, and display settingssuch as monitor resolution and color
Web designers constantly weigh imagequality v. file size/download time
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
19/36
Color Resolution
Also calledBit or pixel resolution
Color, bit, or pixel depth
Measures the number of bits ofstored information per pixel or how
many colors each pixel may containColor resolution chart
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
20/36
Color Resolution
Greater color resolutionHigher quality image
Larger file size
Different color palette
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
21/36
Web-safe color palette
Also calledBrowser-safe color palette and 6 x 6 x 6
palette216 safe colors
Dithering and Banding
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
22/36
Image Resolution
Amount of information stored foreach image
Measured in pixels per inch (ppi)
Computer monitors display 72 ppi
Setting Web graphics higher than 72ppi makes them larger in file size andon screen
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
23/36
Optimizing Images
Crop to smallest area
Apply image size for final Web page
Reduce resolution to 72 ppi
Reduce colors to minimum withoutsacrificing quality
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
24/36
Image Compression
Compression algorithm used tocreate smaller file sizes
Two typesLossless
Lossy
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
25/36
Graphics Software
Include drawing, painting and imageediting programs
Tool palette
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
26/36
Paint Programs
Bitmapped images pixel-basedEditable pixel by pixel
Enlarging may result in jaggiesMicrosoft Paint
Create and edit geometric figures
Add color and patternsCut and pasteRotate and stretch
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
27/36
Draw Programs
Vector graphics mathematical models
Resize without losing image quality
Smooth, precise, versatile
Generally require less memory
May take longer to refresh
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
28/36
Draw Programs
Adobe Illustrator, Macromedia Freehand,CorelDraw
Fully editable shapesBzier curvesGradient fillsBlending/morphing
GroupingRasterizingConverting a vector-based graphic to pixelsImproves refresh rate
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
29/36
3D Modeling Programs
Also called rendering programs
Textures applied to wire-frame model
RenderingConverting a three-dimensional image toa two-dimensional image
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
30/36
3D Modeling Programs
Bryce, Canoma, Carrara,Poser, LightWave,
SoftImageModelingArranging and deformingShading
Setting lights and camerasRendering
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
31/36
Image Editing Programs
Manipulate digitized images
Adobe PhotoShopCropping
Brightness, Contrast, Color Correction
Filters
LayersFile Format Conversion
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
32/36
Enhancement Programs
Plug-insAdd-on features
Programs specifically designed forworking with Web graphics andanimation
Macromedia FireworksAdobe Image Ready
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
33/36
Web Graphic File Formats
Graphics Interchange Format (GIF)
Joint Photographic Experts Group(JPEG)Portable Network Graphics (PNG)
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
34/36
GIF
Developed by CompuServe
Supports 256 colors (8-bits)
Uses lossless compression
Supports interlacing (GIF 87a)
Supports transparency (GIF 89a)Animation
Best for solid color images/diagrams
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
35/36
JPEG
Supports millions of colors
Uses lossy compression
Progressive jpegs support interlacing
Rectangular do not supporttransparency
Best for photographs/continuous toneimages
Harcourt, Inc. items and derived items copyright 2002 by Harcourt, Inc.
-
8/2/2019 Chapter 4 - Graphics
36/36
PNG
Supports various color depths (8-bit to 32-bit)
Uses lossless compressionGenerally creates smaller files than GIF
Supports variable transparency
Supports interlacing fasterCapacity for gamma correction
Not supported by all browsers w/o plug-in
Harcourt Inc items and derived items copyright 2002 by Harcourt Inc