Chapter 6

Tim Berners-Lee- founder of WWW

Painting: bitmapped graphics
Painting software paints pixel on the screen with a pointing device , pointer movements translated onto screen into lines and patterns.

• images stored at 300 dot/inch

pixels: very small colored dots that form and image on a screen

bitmapped graphic/raster graphic- graphics where images are stored and manipulated as organized collections of pixels rather than as shapes and lines.

color depth- bit depth, number of bits in a pixel
resolution- density of pixels measured by number of dot/inch

Image Processing

• allows user to manipulate photos and other high-resolution images with tools like Photoshop
• digital photo management software simplify common tasks that have to do with capturing,organizing, editing, and sharing digital images
• drawing software store pictures as collection of lines and shapes, and stores shapes as shape formulas and text.
• bitmapped images have high demand on storage
• formatting

Object-oriented drawings:

• cleaner lines and shapes
• better for creating graphs and charts

Some programs have both drawing and painting modules
Some merge both modules into one application

3-D Modeling Software
Used to create 3-D objects and animated productions on a screen
Can view the 3-D object from various angles

Computer Aided Design (CAD)

Allows designers to creates designs for products
Ranges from computer chips to public buildings
Cheaper and faster than a design-by-hand technique

Computer Aided Manufacturing (CAM)
process in which data is put into program that controls that manufacturing of parts in the product design

Computer-Integrated Manufacturing (CIM)
combination of CAD/CAM and a major step toward to a fully automated factory

Presentation Graphics
Automates visual aids for presentations
Creates slide shows directly on computer monitors and LCD projectors including still images, animations,and video clips

Tweening
key frames and objects to fill in gaps in in frames

Analog and Digital Video
can convert analog video signals from a TV broadcast or a videotape into digital data

Audio Digitizer- capturing and storing sound into a data file

Synthesizer- electronic instrument that combines sounds using mathematical formulas

Musical Instrument Digital Interface (MIDI)- protocol for code to transfer note information, and system information to a data system or computer or other MIDI device

 Sound data is sometimes called waveform audio.

Recorded sound can take huge amounts of space on disk and in memory. Higher quality sound reproduction requires more memory. The difference is due in part to differences in sampling rate.

Sampling rate- the number of sound “snapshots” the recording equipment takes each second.

 A higher sampling rate produces more realistic digital sounds in the same way that higher resolution produces more realistic digital photographs—it allows for more accurate modeling of the analog source.

Music is digitized on audio CDs at a high sampling and bit depth

New methods of compression, including  MP3,  AAC, and WMA can squeeze music files to a fraction of their original CD-file sizes, often with a great loss of quality.

 

Format	Description
WAV, AIFF	Standard formats for uncompressed audio for Windows and the Mac OS, respectively. Both formats are supported on Windows, Mac OS, and Linux. Both create large files. Both are lossless – a CD track encoded with  WAV or AIFF sounds identical to the original.
MP3	A popular format for transmitting audio on the Internet. A CD track converted to MP3 format can be 1/10 the size of the original – or smaller – but still sound very similar.
WMA	An alternative to MP3 developed by Microsoft for Windows. WMA compression can result in smaller files of higher fidelity. WMA files may be protected by DRM.
AAC	Apple’s alternative to MP3 and WMA is used primarily by iTunes and iTunes Music Store. AAC compression is sonically superior to MP3 compression. AAC files may be protected by DRM.
OGG	Similar to WMA and AAC in sound quality and compression, OGG Vorbis is open source and freely available – not controlled by any company.

Hypermedia combines text, number, graphics, animation, sound effects, music, and other media in hyperlinked documents.

Interactive multimedia- a combination of text, graphics, animation, video, music, voice, and sound effects that allows the user to take interact

Tele-Immersion
Uses various cameras and high-speed networks to create a videoconferencing environment in which multiple remote users can interact with each other and with computer-generated objects
Combines the display and interaction techniques of virtual reality with new vision technologies that allow participants to move around in shared virtual spaces, all the while maintaining their unique ways

Augmented reality (AR)
use of computer displays that add virtual information to a person's sensory perception