Multimedia In Computers Essay, Research Paper
1 Introduction
Multimedia is nothing new. The nature of human communication has always involved multimedia . We hear, speak, write, draw, make gestures, play music, and act out our thoughts and feelings to one another. We have enjoyed multimedia presentations since our childhood through film, television, and, more recently, videotape, videodisc and digital videodisc. These have all involved analog media. What makes recent developments in multimedia new and exciting is that we can now deal with these various media in a digital format.
The digital format allows manipulation, sharing, and merging of data in ways that analog cannot. For example, writers can incorporate digital images into a word processing document. They can record and edit sounds to link with images or text, permitting the data types to serve multiple purposes with a minimum of reworking. Users can program the computer to seek files randomly, to store these different files digitally, just as any computer file. They can edit this information, eliminating unnecessary parts, transforming them, or adding alternative data or special effects all without expensive postproduction.
1.1 What is Multimedia?
Multimedia evokes different images depending on the listener or reader s understanding. Multimedia is defined as an interactive computer-mediated presentation that includes at least two of the following elements: text, sound, still graphic images, motion graphics, and animation (Theoretical Foundations of Multimedia. Robert S. Tannenbaum (c. 1998)). Even the unabridged edition of The World Book Dictionary (c. 1990) leaves room for interpretation by defining the term as using a combination of various media .
1.1.1 Mixed Mode
Some people understand multimedia to mean the use of two or more types of media in the same product. We know that CD-ROMS (Compact Disc-Read Only Memory) can store virtually any type of digitised information. If we can digitise the data, we can also store it on a CD-ROM just as any other type of digital file.
Many applications in the MS-DOS environment that employ multiple media in this way usually use them as discrete elements or as complements to each other just as magnetic disks do. Philips and Dupont Optical Company (PDO) refer to this as mixed mode . It defines a mixed mode CD-ROM as one, which contains computer readable data on track 1 and CD-quality audio on the remaining tracks, 2 through 99 (Multimedia in Practice 1995, p. 23).
1.1.2 Compound Mode
Others understand multimedia to mean the integration of several media within the same application. Philips, Microsoft, and Sony refer to this as compound mode in the introduction to CD-ROM. These types of discs present special problems, which we plan to discuss later on.
Since CD-ROM essentially consists of one long linear medium, it stores data only sequentially, even though it permits random access. In addition, files vary in length and playback requirements. For example, digital images require much more storage space than text. One type of medium may play in a static mode at the same time as another might play in dynamic mode, such as an image displayed on the screen accompanied by audio (music and/or narration) or text accompanied by graphics and audio
(Welcome to Multimedia 1992, p. 67).
1.2 Multimedia Platform
The basic Macintosh computer comes equipped for multimedia. It has high-resolution graphics monitor and built-in audio capabilities. Newer models have colour monitors and faster processors two features that add to the Macintosh s ability to handle new graphics-intensive applications that have animation and video; they just require the addition of a CD_ROM or videodisc player. New hardware add-ons, such as video processors, have the potential to improve the Mac s ability to handle multimedia applications. Apple s extension to the Mac s operating system, called QuickTime, allows software developers to integrate audio and video data types with standard applications (Utilizing Multimedia 1996, p. 12).
Multimedia on the IBM PC and compatible s, on the other hand, comes as a relatively new development. Microsoft announced its specifications for the Multimedia PC in November of 1990. It defines the following minimum standard requirements:
1.2.1 Specifications
+ a 386/486 CPU; 2MB or more of RAM;
+ 30MB or larger hard disk (100MB recommended);
+ VGA (4-bit or 8-bit) video display (640Ч480 resolution minimum; super VGA recommended);
+ 101-key keyboard;
+ two-button, Microsoft-compatible mouse;
+ a digital audio subsystem, consisting of the following:
+ 8-bit digital to analog converter (DAC), linear PCM (pulse code modulation) sampling, 11.025kHz and 22.05kHz sampling rate, DMA/FIFO with interrupt;
+ 8-bit digital to analog converter (DAC), linear PCM sampling, 11.025kHz sampling rate, microphone input;
+ music synthesiser chip;
+ on-board analog audio mixing capabilities;
+ MIDI-in (Musical Instrument Digital Interface) and MIDI-out ports;
+ Serial, parallel, and joystick ports;
+ Joystick or other absolute-pointing device;
+ A CD-ROM drive with CD-DA outputs with an average seek time of 1 second or less; and
+ Systems software compatible with the applications programming interfaces (APIs) of Microsoft Windows 3.0 with multimedia extensions or equivalent APIs.
(Multimedia on the PC 1993, p. 1)
1.2.2 Interactive Multimedia Association s Platform
The interactive multimedia association (IMA) released the first in a series of definitions of classes of multimedia platforms. The proposal presents specifications for the minimum functionality required for what it calls the Interactive Video Personal Computer (IVPC) platform class. The specifications aim to support portable multimedia applications that use full-motion, laserdisc-based video and computer graphics in a video overlay environment.
To encourage multimedia compatibility in the international arena, the IMA proposes IVPC platforms for both the NTSC (EIA RS-170A) and PAL (CCIR 470-1) video standards. NTSC-compatible platforms will carry the identifier IVPC/NTSC ; PAL-compatible platforms will have the identifier IVPC/PAL (The Handbook of Multimedia 1997, p.56).
The specifications include a personal computer based on the Intel x86 microprocessor architecture, a LaserVision-compatible videodisc player, an XY-input device, and a VGA-based overlay board with a compatible monitor. The detailed specifications follow.
1.2.3 Basic Computer System Defined by IMA
+ Processor: At minimum an Intel 80286 or fully compatible processor.
+ BIOS: IBM AT compatible.
+ Bus architecture: IBM AT, IBM Microchannel, or Enhanced Industry-Standard Architecture (EISA).
+ Memory: At minimum, 640KB of random access memory (RAM).
+ Disk storage: A hard disk and at least on e5.25-inch, 1.2MB floppy drive or 3-inch, 1.44MB floppy drive.
+ I/O ports: Appropriate ports as required by the videodisc player and XY-input device. At least one IBM AT-compatible parallel port. A free IBM AT-compatible serial port is recommended but not required because the player and XY-input device may use both COM1 and COM2.
+ Keyboard: Standard IBM AT-compatible keyboard; enhanced AT-compatible keyboard optional.
+ Operating system: MS-DOS or PC-DOS version 3.3 or higher or functionally equivalent operating system operating in real mode.
(Multimedia on the PC 1993, p. 2)
Conclusion
Multimedia applications require lots of storage space, creating a demand for larger disks. As applications continue to increase in size, they will incorporate training or realistic simulations. Applications that currently run directly off a CD-ROM or from a network file server may get transferred to the hard disk to increase performance and speed significantly.
We can expect to see the development of high-performance video processors necessary to implement higher quality real-time compression and decompression of motion video. The requirements for producing thirty frames per second of full-screen, full-motion video push to the limits the processing power of our more powerful microprocessors.
The MPC specification outlines the minimum requirements for creating and using multimedia on the PC. We can expect to see technological improvements and a higher level of requirements as titles become more sophisticated and make greater demands on hardware. We have opened the door to a whole new dimension of computing.
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