Multimedia is the combination of several forms of communication Multimedia is the combination of several forms of communication. It may include text, video, photographs, spoken words, and music. Technology Interactions

Electronic Communication Information is sent and received using electronic devices such as radios, music players, and computers. Electronic communication can use analog or digital signals or a combination of both. Analog communication uses a continuous, varying signal. Digital communication uses separate, distinct signals in the form of binary code.

Waves A wave is a disturbance that transfers energy from one place to another. Sound travels in waves through many materials (media): solids, liquids, and gases. Light also exhibits wave motion. Light does not need any medium; it can travel in a vacuum.

Measuring Waves Wavelength is the distance between the peaks of any two waves. Frequency is the number of waves passing a fixed point per second. Amplitude is the height of the wave.

Radio Like light, radio waves are a form of electromagnetic radiation that can travel through the atmosphere, cables, or even in space. Radio is an example of audio communication. To create a radio signal, sound waves must be converted into electromagnetic waves.

Radio Broadcasting: Creating the Program Performers work in soundproof studios. Microphones change their audio (sound) energy into electrical energy. Engineers work at an audio console in the control room to combine and mix sounds from various sources.

Radio Broadcasting: Transmitting the Program After mixing, the signals are sent to a transmitter. The transmitter combines the program signals with carrier waves that “carry” the program signals away from the transmitter.

AM and FM In AM radio transmission, the amplitude (strength) of the carrier wave changes. In FM broadcasting, the frequency of the carrier wave changes. AM broadcasts can travel longer distances than FM. FM broadcasts are usually of better quality than AM.

Satellite Radio Satellite radio uses digital signals. Radio programs are produced in ground stations and transmitted to a satellite in orbit about 22,000 miles above the earth. The satellite bounces the signals back to satellite radio receivers on earth. The digital signal produces very good sound quality, like the sound of a CD.

Digital Music Players Digital music players use either a solid-state memory chip or miniature hard drive to store music. Music is usually loaded in a digital music player by connecting it to a computer. Music stored in digital music players is usually compressed (reduced) in a format such as MP3 so that it requires less memory.

Television Television combines audio and video communication. Television broadcasting uses essentially the same methods as radio broadcasting. Today, three of every four homes receive their television signals by cable or satellite rather than from broadcast signals.

Planning a TV Program The producer hires a writer to prepare a script and a director to turn the script into a TV program. Storyboards are frequently used to plan TV programs, especially prerecorded programs. Storyboards include sketches that show video to be shot, text for dialogue, and what types of camera shots are needed.

Producing a TV Program Together, the producer and director usually hire the “talent” – anyone who will actually appear on camera in the program, such as actors or news anchors. Directors decide which of several cameras is selected for specific shots. Camera operators, sound technicians, and engineers run the actual equipment.

Broadcasting a TV Program Live broadcasts are usually news shows or sporting events. Most other programs are prerecorded and broadcast later. TV broadcasts send video as AM signals and sound as FM signals.

Aperture and Speed High-quality cameras—digital or film—control the amount of light that enters the camera by the following two methods: The size of the opening that lets the light in—the aperture setting The amount of time that light is let into the camera— the shutter speed

Digital Video Digital video and still cameras both use a CCD, or charge-coupled device, to change light into an electrical signal that can be recorded. Video cameras actually record a series of still images that move quickly enough to create the illusion of motion.

The Internet The Internet is a global network of computers. The World Wide Web (WWW) is the graphical portion of the Internet. Web pages are frequently multimedia. They may include any combination of text, video, photographs, drawings, and sound.

Multimedia Production Steps in creating a multimedia presentation: Planning Designing Gathering material Digitizing Producing Delivering