Information Processes and Technology

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Review questions - Suggested answers

Describe the characteristics of multimedia systems?
A multimedia system combines at least three different types of media to create a multimedia product or multimedia presentation. Media types used in multimedia systems include text, numbers, hypertext images, animation and audio and video. By combining the best features of television, film, graphics, animation, books, magazines and radio multimedia systems have the potential to provide a more engaging experience than any other information medium.
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Identify three hardware devices used for displaying multimedia.
A screen provides immediate feedback about the functions the computer is performing. Screens can display a range of different resolutions and can display text, image and video data.

Speakers are another form of display, used for producing sound. Speakers may be located inside the system unit or may be external and connected via a port or sound card.

Data projectors are display devices which allow audio visual display to an audience when a larger scale is required.
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Identify three types of software used for creating multimedia.
Multimedia is created and displayed using a range of software applications, including:
- authoring software
- presentation software
- html editors
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Identify two file formats for each of the following data types.
- audio: MP3 and WAV
- video: MPEG and AVI
- images: GIF and JPG
- animation: animated GIF and Quicktime
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Describe the differences between print media and multimedia?
A major difference between print media and multimedia is interactivity. Interactivity allows the user to navigate through a multimedia system and select the sequence and content that is displayed.
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For each of the following areas, identify a situation where multimedia is used:
- education and training
  Computer Based Training (CBT) is a type of multimedia product which allows users to learn at their own pace. Information is presented using different media types and allows the user the opportunity to review previous topics.
- leisure and entertainment
  Multimedia systems designed for leisure and entertainment are generally classified
  as computer games. Computer games provide a high level of interactivity. The responses of the user determine the game being played.
- information provision
  A multimedia encyclopaedia is an example of a multimedia system used to provide information. It displays information using text, colour, audio, and video or animation.
- virtual reality and simulations
  Flight simulators are used to train pilots. The external effects, such as changing weather conditions, require high-resolution images and the ability to control different aspects of the system.
- combined areas
  Second Life is an internet based, virtual world video game in which people can interact, play, do business, and otherwise communicate.
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Using the situations you have identified above, list the participants and information technology required for each of the multimedia systems.
- Computer Based Training
  - participants: content providers, system designers, project managers, technical staff, trainees
  - hardware: personal computer system, keyboard, mouse
- Computer Games
  - participants: content providers, system designers, project managers, technical staff, players
  - hardware: personal computer system, joystick, steering wheel, gamepad
- Multimedia encyclopaedia
  - participants: content providers, system designers, project managers, technical staff, readers
  - hardware: personal computer system, CD drive
- Flight simulators
  - participants: content providers, system designers, project managers, technical staff, trainees
  - hardware: exact replicas of the cockpit instruments, switches and other controls
- Internet based, virtual world video games
  - participants: content providers, system designers, project managers, technical staff, players
  - hardware: personal computer system, modem
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Briefly describe how improvements in bandwidth, increased storage capacity and powerful CPUs have influenced the development of multimedia?
Improvements in bandwidth has allowed multimedia to be displayed on the Internet. Improvements in storage capacity have allowed better-quality images to be a part of the multimedia production. Increases in processing speed have allowed video and animation to move at realistic speeds.
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Explain how the types of software below can be used in multimedia systems:
- presentation software
  Presentation software is used to create a presentation for an audience. A presentation consists of a series of slides. Each slide may contain text, graphics, animation, audio and video.
- authoring software
  Authoring software is used to combine text, graphics, animation, audio and video. It allows the creation of interactivity. The creation of interactive online quizzes is an example of an application of authoring software.
- animation software
  Animations created by animation software may be integrated into web pages, presentations, videos and a range of other multimedia products.
- web browsers/HTML editors
  HTML editors are programs which are used to generate HTML code used in web pages. Web browsers are used to display web pages. Web pages are capable of displaying a range of media types.
- video processing software
  Video software is used for editing video footage. Editing video involves adding text, audio and images to a video clip. A variety of effects can be added and segments of different videos can be as combined into one production
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Explain the purpose of storyboards in terms of organising multimedia.
Storyboards consist of navigation paths, information and graphics. They are simple to construct, easy to read and can be modified at every stage. Storyboards provide an easy to follow visual plan of a multimedia presentation.
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Describe the three main layouts of a storyboard; use diagrams to illustrate your answer.
- Linear: a sequential series of frames. This layout is commonly used to plan videos or presentations that follow a sequence.
- Hierarchical: A top-down layout where the user moves from the top level and proceeds through a series of sub levels. This layout is commonly used to plan web sites or presentations that are organised into categories and sub categories.
- Non-linear: This layout has no particular structure. The user moves from one layout to the next in any direction. This layout is commonly used in games.
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Describe one method of audio data compression.
MP3 compresses a file by removing the high and low frequencies out of human hearing range. MP3 uses a compression ratio of 11:1. MP3 compression allows large audio files to be dramatically reduced in size, allowing them to be easily transferred and downloaded with little noticeable loss of quality.
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Describe one method of video data compression.
MPEG files achieve a high compression ratio by using lossy compression and only storing the changes from one video frame to another. Background elements which do not move need not be preserved in all frames. This reduces file size.
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Outline the significance of codecs in terms of multimedia systems.
A CODEC (coder-decoder) is used to encode and decode (or compress and decompress) various types of data. A CODEC is typically used with sound and video files. CODECs convert analog video signals into compressed video files, such as MPEG, or analog sound signals into digitised sound, such as RealAudio.
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Explain the process of morphing as it applies to digital images.
Morphing is a special effect in motion pictures and animations that changes (or morphs) one image into another through a seamless transition. Digital morphing involves distorting one image at the same time it fades into another through marking corresponding points and vectors on the "before" and "after" images used in the morph.
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Outline the role of content providers in the development of multimedia applications.
Content providers provide the material for the multimedia product. This may include text, graphics sketches or final drawings, video footage and audio tracks. Generally these people are skilled in their field without necessarily having any technical skills in the software or hardware areas.
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Outline the role of project managers in the development of multimedia applications.
Project managers organise the scheduling of various components, provides overall supervision and ensures that all components are delivered on time.
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Define the term 'hypermedia'.
Hypermedia is extension to hypertext that supports linking graphics, sound, and video elements in addition to text elements. The World Wide Web is a partial hypermedia system since is supports graphical hyperlinks and links to sound and video files. Hypermedia allows a series of independent documents or files to be linked using hypertext.
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Research a virtual world and and explain why this computer-based environment is an example of a multimedia system.
Second Life is an Internet-based virtual world video game launched on June 23, 2003, developed by Linden Research, Inc. A free downloadable client program called the Second Life Viewer enables its users, called "Residents", to interact with each other through motional avatars, providing a social network service.

Second Life allows users to create avatars; images that may resemble the person they represent or may be more creative. Avatars are able to move around the virtual environment in a number of ways. There is a 3D modelling tool in Second Life that allows any Resident with the right skills to build virtual objects: buildings, landscape, vehicles, furniture, and machines to use, trade, or sell. There are two main methods of text-based communication: local chat, and global "instant messaging" (known as IM). Chatting is used for public localized conversations between two or more avatars, and can be heard (seen messages) within 20 m. Objects can also use the chat channels.
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Research the emerging technology of digital radio and outline the features it offers as compared to traditional analog radio.
Digital radio is a method of transmitting radio signals. It allows a range new features to be included in broadcasts. Since it uses the radio spectrum more efficiently, digital radio offers many significant advantages over analog radio.

Digital radio is different to AM and FM radio as, instead of being made up of analog waves, the radio signal is transmitted digitally. Digital radio signals are far less likely to be affected by adverse weather conditions or local sources of interference. Digital radio uses a combination of MPEG-2 Audio Layer II and COFDM (Coded Orthogonal Frequency Division Multiplex) technology that converts the music or speech from analog signal into a digital stream. Digital radio allows a flexible audio bit-rate between 32 kbit/s and 256 kbit/s; this is reflected in the amount of bandwidth taken up by the coded audio component.

Digital radio transmission has the potential to offer new services to expand listeners' choice. There is no need to remember the frequencies of stations, as tuning can be done by station name. Digital radio receivers are essentially computers that receive and decode a digital program stream. Like computers, they also have the capacity to store information. Digital radio receivers can therefore pause, rewind for a few minutes or store audio (via a memory card) for later listening. Digital radio receivers also have small screens for text information about the programs on air. This might include song and artist details, the latest news and weather, business news and sports results, what's coming up next, website addresses and contact phone numbers. As digital radio
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References:

Powers, G.K. Information Processes and Technology, HSC Course, Heinemann, Melbourne, 2003
G Johnstone, M Lowbridge, J Smith, Information Processes and Technology Excel HSC Study Guide, Pascal Press, Sydney, 2001
CAST, Universal Design for Learning, http://www.cast.org/publications/ncac/ncac_vr.html N Strangman & T Hall, 25/06/2008
Webopedia Computer Dictionary, Hypermedia, http://www.webopedia.com/TERM/H/hypermedia.htm 25/06/2008
Personal Computer Game, Wikipedia, http://en.wikipedia.org/wiki/Computer_games 25/06/2008
Flight Simulator, Wikipedia, http://en.wikipedia.org/wiki/Flight_simulator 25/06/2008
Multimedia, Wikipedia, http://en.wikipedia.org/wiki/Multimedia 26/06/2008
Virtual Reality, Wikipedia, http://en.wikipedia.org/wiki/Virtual_reality 26/06/2008
Morphing, Wikipedia http://en.wikipedia.org/wiki/Morphing 26/06/2008
Second Life, Wikipedia, http://en.wikipedia.org/wiki/Second_life 26/06/2008
ABC Radio, Digital Radio, http://www.abc.net.au/radio/digital/ 26/06/2008
Digital Radio Australia, How Does Digital Radio Work, http://www.digitalradioaustralia.com.au/index.cfm?page_id=1024 26/06/2008