1. CSCI 1200 Introduction to Computing for Non Majors CHAPTER 6 Tami Meredith, Ph.D. tami.meredith@live.com

2.  Be aware of the various different types of image-processing and drawing software  Explain effective techniques for improving the quality of slides prepared with presentation-graphics software  Describe how data compression works  Describe several present and future applications for multimedia technology 2

3.  Pixels: tiny dots of white, black, or color that make up images on the screen  RGB: Colour model that is typically used  More pixels isn't necessarily better  HD (most common): 16:9,1366x768  Printers can reach higher resolution but colour quality depends on inks used 3

4.  Bitmapped graphics (or raster graphics): pictures show how the pixels are mapped on the screen › Gray-scale graphics: uses 8 bits per pixel; allows up to 256 shades of gray › Color depth: number of bits devoted to each pixel (typically 24) › Resolution: density of the pixels; described as DPI (dots per inch) › Anti-aliasing: smoothes out less-than-ideal resolutions 4

5.  Paints pixels on the screen with a pointing device  Pointer movements are translated into lines and patterns on the screen  Palette of tools mimics real-world painting tools  Microsoft Paint

6.  Image processing: users manipulate photographs with tools such as Adobe Photoshop or GIMP  More powerful than traditional photo- retouching techniques  Can distort and combine photos  Can create fabricated images that show minimal evidence of tampering 6

7.  Digital photo management software programs simplify and automate common tasks associated with capturing, organizing, editing, and sharing digital images  Apple iPhoto, Google Picasa, Adobe Lightroom 7

8.  Vector graphics consider a picture as a set of lines and shapes  Better for logos, comics, and things with crisp borders, fewer colours  More scalable than raster graphics (bitmaps)  Many drawing tools—line, shape, and text tools—are similar to painting tools in bitmapped programs 8

9.  Bitmapped painting (pixels) gives you these advantages: › More control over textures, shading, and fine detail › Appropriate for screen displays, simulating natural paint media, and embellishing photographs  Vector Graphics give you: › cleaner lines › smoother shapes › improved scalability  Some programs contain both drawing and painting modules or provide both raster and vector tools › Allows you to choose the right tool for each job › Blurs the distinction between types 9

10.  Portable Document Format  Successor to Postscript (based on the Forth programming language)  File format developed by Adobe; enables digital documents to be exchanged between programs independent of application software, hardware, or operating system › Can contain text, fonts, images, and vector graphics › Can be displayed by Web browsers using Adobe’s Acrobat Reader 10

11.  used to create three-dimensional objects with tools similar to those in drawing software  draw a 3-D model, rotate it, view it from different angles  can create an animated presentation rather than a printout  can “walk-through” a 3-D environment that exists only in the computer’s memory  Blender, Maya 11

12.  (CAD) computer-aided design allows engineers, designers, and architects create designs on screen products ranging from computer chips to public buildings  Can test product prototypes  Potentially cheaper, faster, and more accurate than traditional design-by- hand techniques 12

13.  CAM (computer-aided manufacturing): process by which data related to the product design are fed into a program that controls the manufacturing of parts  CIM (computer- integrated manufacturing): combination of CAD/CAM 13

14.  Static: Fixed and unchanging  Dynamic: Changing  Digital media may contain dynamic multi- format information that changes over time or in response to user input › Animation › Video › Audio › Hypertext 14

15.  Presentation graphics: automates creation of visual aids for lectures, training sessions, sales demonstrations, and other presentations  Creates slideshows directly on computer monitors or LCD projectors, including still images, animation, and video clips  Powerpoint, Keynote 15

16.  SHORT! Some presenters advocate the use of only 3 slides (title, body, summary)  Augment the speaker, don't replace the need to listen to the speaker  Not distracting from the speaker  Unify the various elements (movies, text, audio, etc.)  Simple and minimalist

17.  CGI (Computer generated imagery) animation  Each frame is a computer-drawn picture; frames are displayed in rapid succession  Key Framing (Tweening): instead of drawing each frame by hand, the animator can create key frames and objects and use software to help fill in the gaps  Wireframe: Objects represented by skeletal structures (without textures on them)  Mocap: Motion capture to use human motion as the basis of the animation  Vector graphics formats include Shockwave Flash Format (SWF) and Scalable Vector Graphics (SVG) 17

18.  Signals can be sent using waves  In analog, we use the height and frequency of the waves to encode information  In digital, we convert the information into binary and then use the wave to transmit the binary data

19.  Analog (archaic, pretty much gone) › A video digitizer can convert analog video signals from a television broadcast or videotape into digital data › Many video digitizers can import signals from televisions, videotapes, video cameras, and other sources  Digital › Digital video cameras capture footage in digital form › Digital video can be copied, edited, stored, and played back without any loss of quality 19

20.  Predominantly digital today  Nonlinear editing of clips stored on the hard disk can be done in any sequence  Video and sound both just digital, more easily combined  Video-editing software, such as Adobe Premiere, lets editors: eliminate extraneous footage, combine clips from multiple takes, insert visual transitions, superimpose titles, synchronize a soundtrack, and create special effects 20

21.  Saves storage space – also less to send over a network  Savings in network transmission offset by time/cpu use for decompression  Playback devices use some form of compression: e.g., QuickTime, Windows Media Player  Various codecs (coder-decoder) to facilitate different compression techniques › Lossy – Compression and decompression results in lost information (usually detail) › Lossless – Compression and decompression has impact 21

22.  Synthesized: computer reproduction of sound  Sound data is sometimes called waveform audio. › Recorded sound can consume massive amounts of space on disk and in memory. › Higher quality results from higher sampling rates. › Number of sound “snapshots” the recording equipment takes each second 22

23.  Synthesizer: electronic instrument synthesizes sounds using mathematical formulas  MIDI (musical instrument digital interface): standard interface allows electronic instruments and computers to communicate with each other  Sequencing software: used to interpret the sequence of MIDI commands 23

24.  A piano-style keyboard sends MIDI signals to the computer; computer interprets the MIDI commands using sequencing software 24

25.  Sequencing software: turns computer into musical composing, recording, and editing machine  Virtual instruments: instruments that exist only in software – generate binary data that is saved in MP3 or other format 25

26.  Understand piracy and copyright issues  Understand downloading and streaming  Know your file formats  Don’t over-compress  Use appropriate hardware, devices, instruments – don't try to do it all on a computer 26

27. 27 Popular digital audio formats

28.  Hypertext: information linked in nonsequential ways  Hypermedia: combines text, numbers, graphics, animation, sound effects, music, and other media in linked documents › Useful for online Help files › Enables the user to jump between various distributed documents  WWW is the best example of a hypertext (based on HTML – Hypertext Markup Language) 28

29.  Hypermedia documents can be disorienting and leave you wondering what you’ve missed  Documents don’t always have the links that are wanted/needed › Authors can’t build every possible connection into documents › Some readers get frustrated because they can’t easily get “there” from “here” 29

30.  Documents sometimes contain “lost” links, especially on the Web, where even a popular page can disappear  Documents don’t encourage scribbled margin notes, highlighting, or turned page corners for marking key passages.  Hardware can be hard on humans  Our understanding and use of hypermedia is still in its infancy 30

31.  Multimedia: combination of text, graphics, animation, video, music, voice, and sound effects allows the user to take an active part in the experience  Requirements: high-quality color monitors, fast processors, large memory (CD–ROM drives), speakers, and sound cards (+ network connections)  Many of today’s Internet connections can’t deliver large media files quickly enough 31

32.  Multimedia authoring software: used to create and edit multimedia documents › Uses authoring programs such as Adobe Flash › Binds source documents together to communicate with users in an aesthetically pleasing way › Also used to describe software for making movies (with video & audio mixed together) 32

33.  Be consistent  Make it intuitive and easy to use  Strive for simplicity  Message more important than the media  Use user-centric design  Do usability testing 33

34.  Virtual reality combines virtual worlds with networking › Places multiple participants in a virtual space › People see representations of each other, sometimes called avatars › Most avatars today are cartoonish, but they convey a sense of presence and emotion › Becoming more immersive/3D via use of devices such as an Occulus Rift 34

36.  Tele-immersion allows multiple-remote users to interact with each other and with computer-generated objects › Participants move around in shared virtual spaces, while maintaining their unique points of view.  AR (augmented reality) adds virtual information to your sensory perceptions 36

38.  The interactive nature of the personal computer makes it possible to create nonlinear documents that enable users to take individual paths through information  Multimedia can combine text, graphics, animation, video, music, voice, and sound effects  Computer input devices enable an active experience not possible with passive devices such as television 38