Multimedia—combining different media to express information or ideas.

A multimedia event can include text, graphics, sound, video, and animation.

Forms of multimedia—CDs, DVDs, games, television programs, movies, information kiosks (an automated system to provide information or training, includes a touch screen for input.)

Television and Movies are one-way multimedia

Interactive multimedia allow the user to make choices about what is displayed.

To be interactive, a multimedia event must provide more than audio or video.

It must also give the user a way to control the action.

In an interactive program, you make choices that determine what happens next.

Examples of interactive multimedia—computer and video games, educational computer software, and some Web sites.

Multimedia applications are widely used today in business, education, and entertainment.

Business-multimedia technologies help businesses communicate with their customers and employees, make their sales and training presentations more vivid, and many corporate Web sites use, sound, video, or animation to demonstrate products to their customers.

Education—multimedia can make learning more fun for students and provides extra tools for teachers.

Animation and video make difficult concepts easier to understand.

Interactive software can teach lessons, present quizzes, and give students immediate feedback to help them see how well they are doing.

Multimedia programs offer audio and video to enhance learning in ways that printed text alone cannot.

Entertainment—No industry makes more creative use of multimedia than the entertainment industry.

Video and computer games, flight simulators, action games, 3-D animated movies, concerts, and television programs all incorporate multimedia on a regular basis.

Special tools are needed to create multimedia presentations.

Sound card—a special expansion board that allows the computer to input, edit, and output sounds.

Audio is entered into the computer through the input jacks on the sound card.

Once audio is captured on the computer’s hard drive, you can edit and work with it.

You can then play it through the computer’s speakers or headphones, or save it to a disc.

You can also send it to another audio device using the sound card’s output jack.

Full-featured cards even include optical inputs and outputs for digital sound and special software for mixing sound.

Video Capture Board—a special card that plugs into a computer that converts video signals into a format that computers understand.

You can transfer video to the capture board from camcorders, VCRs, digital cameras, and other sources.

Video Editor—a program that allows you to cut and paste sound and video segments and change the order in which segments appear.

Video editors also allow you to define the frame rate, or how many still images are displayed in one second, and specify the speed at which video should be displayed.

Pen-Based Graphics Tablets—when creating still or animated graphics for use in a multimedia program, many artists find it easier to draw and sketch using a pen-based graphics tablet rather than a mouse.

To use the tablet, you move a stylus, or electronic pen, across a sensitive touchpad, and your movements are recorded by your graphics software.

The images can then be saved and edited.

Microphones—audio can be recorded into a conventional recording device and then imported through a sound card.

Audio can also be recorded directly into the computer using a microphone.

Most sound cards have a special plug for a microphone.

Using the software that comes with the sound card, you can assign a file name, click “record,” and start speaking into the microphone.

The sounds will be recorded to a new audio file. Digital cameras are also an easy way to get

images into a computer for use in multimedia.

MPEG—a family of formats developed by the Moving Picture Experts Group.

Web sites and CD-based products commonly use MPEG to display video such as movie clips, animations, and recorded television broadcasts.

MPEG files offer full-motion video so they give a very realistic effect.

MPEG-2 improves on the basic MPEG format and can be stored in a much smaller file.

The quality of the video is as high as a television set can display, and the audio is CD-quality.

MPEG-2 is the format used in DVDs.

QuickTime--designed by Apple Computer, is the basic file format for showing animation and video on Macintosh computers.

QuickTime videos also can be viewed on Windows computers, but a special player must first be installed.

The QuickTime format is often used for high-quality movie trailers shown on Web sites.

It is also used for the video feeds from Web sites that provide news and weather information.

AVI—Audio Video Interleave, is another name for Microsoft Video for Windows format.

Some AVI videos are not of the best quality, but they can be played on any Windows computer.

Many businesses create their multimedia in AVI format to tap into the huge market of Windows users.

MP3—MPEG audio layer 3 files are very common today, thanks to the ease of downloading music from the Internet.

The MP3 format takes a large audio file and makes it very small.

It does this using regular compression methods and also by removing data from the music file that the human ear cannot hear.

This results in a much smaller file, with little or no loss of sound quality.

WMA—the music format of Microsoft. It stands for Windows Media Audio.

AU—the standard format for audio files for the UNIX operating system.

WAV—the waveform audio format is built into the Microsoft Windows operating system.

WAV files can be played on almost any computer system.

WAV and WMA files can be converted into MP3 files using a hardware device or special software programs called encoders that convert the files from one format to another.

MIDI—Musical Instrument Digital Interface is a standard that allows a computer to control a musical instrument.

MIDI sounds are synthesized. This means that sounds imitative of musical instruments are generated by the computer when they are played; no actual recorded sound is stored in the file.

Multimedia presentations aren’t limited to files stored on your computer’s disks.

With an Internet connection, you have access to an unlimited number of multimedia experiences.

Many multimedia Web sites can stream video and audio data—that is transmit it across a network without interruption.

You don’t have to wait until the entire file is downloaded to your computer for it to play. The file begins playing as soon as it starts to download from the Web site to your PC.

Net Radio—Internet radio is a method for listening to music, talk, and information over the Internet.

Net Radio doesn’t actually use radio waves. Instead audio programs are converted to digital format and streamed across the Internet.

Streaming radio places a temporary audio file on your hard drive. This is what is heard—not the actual stream.

The audio stream replenishes the file on the hard drive, continually updating the data as it plays.

Net Video—uses streaming to deliver pictures as well as sound. News sites use online video to deliver the latest news.

Movie sites preview upcoming releases and offer short films an animations.

In the business world, Net video is used for video conferencing.

in a videoconference, small cameras are used to allow people in different places to see and hear one another.

If your computer has a CD-Rom drive, you can also copy music for your personal use from audio CDs onto your hard drive.

This process is called ripping, and it requires special software.

Once audio is ripped to the hard drive, it can be converted to MP3 format, which creates a much smaller file than a regular audio file.

Windows Media Player—comes installed with Microsoft Windows and plays most video and audio formats.

It lets you design playlists and save those playlists for later use.

QuickTime Player—there are versions for both Macintosh and Windows.

QuickTime can handle a number of video and audio formats.

You can also use it to play video from a digital camcorder.

It is available as a free download, or you can buy a version that lets you convert media files from one format to another and do advanced editing.

RealOne Player—plays many different audio and video formats.

Lets you create a playlist and your own CD collections.

One version is available as a free download.

A more powerful version is available for a fee.

Windows Media, QuickTime and RealOne Players are all very popular.

They can handle a wide variety of audio and video formats, although each one has its own unique format.

Many people have all three of these players installed on their computer.

Macromedia Flash and Shockwave Players—multimedia developers can use these special file programs to create interactive multimedia content, such as animated games.

These programs can accept user input, use high-quality audio and graphics, and are very small so they can be downloaded quickly from a Web site or disk.

To view content created in these programs you need the Flash Player and the Shockwave Player, both of which are free.

Audio, video, graphics and text are the pieces you must put together to create a multimedia event.

You put these together using software called authoring tools.

Authoring tools let you choose which sounds, video clips, animations, text, and graphics will appear.

You can also control timing, transition effects, and volume.

Authoring tools let you respond to the following questions: How long will each image appear on-screen? How will one clip fade into the next? How loud should each sound clip be?

Most authoring tools save their information in a format for use only by the software developers and authorized users.

To view the finished piece, users need special software.

This can be either a stand-alone media player or a browser plug-in that can be downloaded from the Internet.

Some authoring tools are for media professionals.

Others can be used by students to create their own CDs, videos, and interactive kiosks.

Students can use these tools to create Web pages and complete special projects related to their assignments or to their own interests.

The professional version of QuickTime and some high-end desktop publishing programs include a small set of multimedia authoring tools.

The term virtual reality, or VR, is used to describe three-dimensional, computer-generated environments that you can explore by using special hardware and software.

Such environments simulate spaces of various kinds, such as the flight deck of an airliner.

The purpose of all VR environments is the same: to let users explore every aspect of space, moving in any direction, just as if that space was real.

In some cases, VR worlds are displayed on regular computer screens.

Architects use computer-aided design software to design 3-D walk-throughs of a building before it is built.

Virtual reality often uses a special helmet called a head-mounted display, or HMD, to make you feel as if you’re in another place.

A set of goggles wraps around the head, blocking out light.

A tiny computer monitor is located in front of each eye.

Using these two separate monitors gives the illusion of three dimensions.

HMDs often have headphones to provide audio to the user.

In advanced HMDs, tiny sensors can tell when the user’s head tilts in any direction.

The image on the monitors then shifts accordingly, in order to create a convincing illusion of being part of the action, rather than a spectator of it.

Data glove—a basic glove equipped with sensors that measure movements of the hand and fingers.

One use of the data glove is to operate equipment from a distance.

CAVE—Cave Automatic Virtual Environment is an expensive and advanced form of VR.

Images of a virtual world are projected on the walls of a room.

Visitors wear special goggles that create the illusion of three dimensions.

The result is so realistic and so convincing that most explorers cannot tell where reality ends and virtual reality begins without reaching out and touching something.

In many CAVEs, users wear special gloves or hold special wands, either of which can detect hand movements.

These devices allow users to interact with objects in the virtual world, by opening doors, for example, or picking up the pieces in a virtual chess game.

Virtual Worlds Online—to create virtual worlds on the Internet, programmers use a language called Virtual Reality Modeling Language, or VRML.

VRML allows programmers to describe objects that appear in the virtual world.

The objects can be shapes, buildings, landscapes, or characters.

To view VRML Web pages, you may need to download and install a special plug-in for your browser.

Virtual reality has become very useful for simulations.

Simulations are virtual reality programs that mimic a specific place, job, or function.

These simulations can be very valuable in training, education, and other fields.

Virtual reality is used in many design and architectural businesses.

It is used in the military to train fighter pilots and combat soldiers without the risks of live training.

In medicine, virtual reality is used to simulate complex surgery for training surgeons without using actual patients.

Easing pain—At the University of Washington’s Harborview Burn Center, virtual reality is being used to help severe burn victims deal with their pain.

Patients are immersed in a virtual reality environment where they imagine that they are flying through icy canyons and cold waterfalls.

By focusing on things that are pleasant and cold, patients can focus less on their pain.

Overcoming Fear—a study by Walter Reed Army Hospital and Emory University School of Medicine showed that patients placed in virtual reality flight simulators overcame their fear of flying as successfully as patients treated using other techniques.

This technique is cheaper and easier than taking the patients on real airplane flights.

Saving Lives—Heart surgeons often need to replace portions of a heart and its valves with artificial pieces.

Designing replacement valves is very tricky, because even minor flaws can cause major problems.

Scientists at the University of Sheffield in England have developed a way to use virtual reality to test new heart valves before they are manufactured, using a computer to simulate how blood will flow through them.

This software lets doctors predict whether or not the valve will work properly after it is in the body.