Now you can answer what multimedia is. It is not just one thing, but a complex combination of many things: hardware, software and the interface when they meet. No, we forgot the most important thing. Multimedia also includes you. Well, yes! For multimedia, you are no longer a passive audience, you can control it, you can interact with it, and you can make it do what you need. In a report, you can go directly to find important data regardless of those useless things, and you can sort out reports and photo collections from all over the world that you are interested in. This is the power of multimedia and the difference between it and traditional media (such as books and TV).
What can multimedia do? It displays information, exchanges ideas and expresses emotions. It allows you to see, hear and understand other people's ideas. In other words, it is a way of communication. Sound, images, graphics, text, etc. It is not accurate because it is easily confused with material media (also called media) that carry information for transmission and storage, such as electromagnetic wave, light, air waves, current, magnetic media and so on. Nowadays, however, the term multimedia is almost synonymous with words, graphics, images and sounds. In other words, most people think that multimedia is a combination of sound, image and graphics, so this inaccurate word has been used in general articles. At present, the popular multimedia concept mainly refers to a variety of information types that can be directly felt and understood by organs such as words, graphics, images and sounds, which has become a narrow understanding of multimedia.
In the field of computer and communication, what we mean by words, graphics, sounds, images and animations can all be called media. From the perspective of information processing by computers and communication equipment, we can classify the forms of original information in nature and human society-data, words, spoken language, sound, painting, animation and images (still photos and moving movies, television and video) into three basic media: sound, picture and text. Traditional computers can only deal with a single medium-"text", and television can spread information that integrates sound, picture and text, but it is not a multimedia system. Through TV, we can only passively accept information from one direction, but can't actively process information from two directions, so there is no so-called interactivity. Although videophone is interactive, we can only hear the sound and see the image of the speaker, and it is not multimedia. The so-called multimedia refers to the technology that can simultaneously collect, process, edit, store and display two or more different types of information media, including words, sounds, graphics, images, animations and moving images.
In daily life, there are many things called media, such as bees spreading pollen and flies spreading germs. But accurately speaking, these so-called "media" are communication media, not what we call "media" in multimedia, because these communication media are all some kind of material entities, while words, sounds, images and graphics are not material entities, they are only the superficial characteristics of some attributes of objective things, and they are a way of expressing information. What we call "media" in the field of computer and communication is the carrier of information storage, dissemination and expression, not the general media and media.
Conceptually speaking, "media" in multimedia should refer to a form of expressing certain information content. Similarly, we can know that the multimedia we refer to should be the expression of various information or the types of various information. Naturally, we can use the concept of multimedia information to represent comprehensive information types containing different information types, such as text information, graphic information, image information and sound information.
In a word, because the most essential concept of information is the superficial characteristics of objective things' attributes, and its manifestations are various, a more accurate and comprehensive definition of multimedia should refer to the synthesis of various information types.
These media can be graphics, images, sounds, characters, videos, animations and other forms of information expression, display devices such as monitors, speakers and televisions, intermediate media such as optical fibers, cables and electromagnetic waves that transmit information, and storage entities such as magnetic disks, optical disks and magnetic tapes that store information.
[Edit this paragraph] The characteristics of multimedia
Multimedia technology has the following main features:
(1) integration can acquire, store, organize and synthesize information through multiple channels.
(2) Controlled multimedia technology is a computer-centered comprehensive processing and control of multimedia information, which is displayed in various media forms according to people's requirements and acts on people's various senses at the same time.
(3) Interactivity Interaction is one of the main characteristics that distinguish multimedia applications from traditional information exchange media. Traditional information communication media can only spread information in one direction and passively, while multimedia technology can realize people's active choice and control of information.
(4) The nonlinear characteristics of nonlinear multimedia technology will change people's traditional sequential reading and writing mode. In the past, people mostly used the framework of chapters, sections and pages to acquire knowledge step by step, while multimedia technology will present the content to readers in a more flexible way with the help of hypertext links.
(5) Real-time when the user issues an operation command, the corresponding multimedia information can be controlled in real time.
(6) Convenience of information use Users can use information according to their own needs, interests, task requirements, preferences and cognitive characteristics, and can take any form of information such as pictures, words and sounds.
(7) Dynamic information structure "Multimedia is a book that can never be read". Users can reorganize information, add, delete or modify nodes and re-establish links according to their own purposes and cognitive characteristics.
1. The definition of multimedia
The word "Multimedia" is translated from the English word "multimedia", which is a compound of mutiple and media. The original meaning of media is twofold. One refers to entities that store information, such as magnetic disks, optical disks, magnetic tapes, semiconductor memories, etc. , which is often translated into media in Chinese, refers to the carrier of information, such as numbers, words, sounds, graphics and so on. And Chinese translation as a medium. So the word for multimedia is Monomedia. Literally, multimedia is composed of mono media.
Multimedia technology has different definitions from different angles. For example, some people define that "a multimedia computer is a set of hardware and software equipment; Combining various visual and auditory media can produce impressive audio-visual effects. In visual media, it includes graphics, animation, images and words, while in auditory media, it includes language, stereo and music. Users can access various media sources from multimedia computers at the same time. " Others define multimedia as "the combination of traditional computing media (words, graphics, images and logical analysis methods) with video, audio and interactive applications for knowledge creation and expression". To sum up, multimedia technology is the interactive comprehensive processing of multimedia information-words, graphics, images and sounds by computers, which makes all kinds of information logically linked and integrated into a system for interaction. In short, multimedia technology is a computer technology that comprehensively processes audio, video and graphic information, which is integrated, real-time and interactive. )。 Multimedia has its own definition in China. Generally speaking, multimedia technology refers to the technology that can handle information on various carriers (media) and information on various storage bodies (media).
2. Key technologies of multimedia
Because the multimedia system needs to achieve a unified structure code stream of different media data tables, and then convert, reorganize and analyze them for further storage, transmission, output and interactive control. Therefore, the traditional key technologies of multimedia mainly focus on the following four categories: data compression technology, large-scale integrated circuit (VLSI) manufacturing technology, large-capacity optical disk, and real-time multi-task operating system. Due to the breakthrough in these technologies, multimedia technology has developed rapidly and become a high-tech technology with strong ability to handle media information such as sound, text and images as it is today.
However, when talking about the key multimedia technologies to be used in the Internet, some experts think that it can be divided into six aspects: media processing and coding technology, multimedia system technology, multimedia information organization and management technology, multimedia communication network technology, multimedia man-machine interface and virtual reality technology, and multimedia application technology. It should also include multimedia synchronization technology, multimedia operating system technology, multimedia middleware technology, multimedia exchange technology, multimedia database technology, hypermedia technology, content-based retrieval technology, QoS management technology in multimedia communication, multimedia conference system technology, multimedia video-on-demand and interactive TV technology, virtual reality space technology and so on.
3. Components of Universal Multimedia System
A general multimedia system consists of the following four parts:
Multimedia hardware system, multimedia operating system, media processing system tools and user application software.
★ Multimedia hardware system: including computer hardware, audio/video processor, various media input/output devices and signal conversion devices, communication transmission devices and interface devices. Among them, the most important ones are multimedia information processing chips, boards and optical disk drives developed according to multimedia technical standards.
★ Multimedia operating system: or multimedia kernel system, with real-time task scheduling, multimedia data conversion and synchronous control to drive and control multimedia devices, graphical user interface management and other functions.
★ Media processing system tool: or multimedia system development tool software, which is an important part of multimedia system.
★ User application software: an application software customized according to the requirements of the end users of multimedia systems or a user application software system in a certain field, which is a system product for large-scale users.
All kinds of coded data representing media are stored in the form of files in the computer, which is a collection of binary data. The naming of files follows specific rules and usually consists of a main name and an extension. The main name and the extension are separated by ".",and the extension is used to indicate the format type of the file.
Types and characteristics of multimedia information
(1) Text is an information form expressed by words and various special symbols, and it is the most widely used way of information storage and transmission in real life. Expressing information in words gives people full imagination, which is mainly used for descriptive representation of knowledge, such as explaining concepts, definitions, principles and problems, and displaying titles, menus and other contents.
(2) Image is one of the most important forms of information expression in multimedia software, and it is the key factor to determine the visual effect of multimedia software.
(3) Animation Animation is to quickly play a series of graphic images with continuous motion changes by using the persistence characteristics of human vision, including scaling, rotation, transformation, fading in and out and other special effects. Through animation, abstract content can be visualized, and many difficult teaching content changes are vivid and interesting. Rational use of animation can achieve twice the result with half the effort.
(4) Voice is one of the most convenient and familiar ways for people to convey information and exchange feelings. In multimedia courseware, sound can be divided into three categories according to its manifestations: explanation, music and effect.
(5) Video images Video images have time series and rich information connotation, and are often used to explain the development process of things. The video is very similar to the familiar movies and TV shows. It is vivid and plays an important role in multimedia.
[Edit this paragraph] Multimedia system
Multimedia computer system is not a single technology, but the integration of various information technologies, which are comprehensively applied to a computer system to realize various functions such as information input, information processing and information output.
A complete multimedia computer system consists of multimedia computer hardware and multimedia computer software.
First of all, the hardware of multimedia computer
The main hardware of multimedia computer includes audio information processing hardware, video information processing hardware and CD-ROM besides the conventional hardware such as host, floppy drive, hard disk, monitor and network card.
(1) sound card is used to process audio information. It can carry out analog-to-digital conversion (A/D) and compression on the sound information input by microphones, tape recorders and electronic musical instruments. It can also restore (decompress) and D/A the digitized sound signal processed by the computer, and then play it out with a loudspeaker or record it with a recording device.
(2) The graphics card is used to support the input and output of video signals (such as TV).
(3) The acquisition card can convert TV signals into computer digital signals, which is convenient for editing, processing and color control of the converted digital signals with software. The processed digital signal can also be output to the video tape.
(4) The scanner scans the words, images and even objects on photographic works, paintings or other printed matter into the computer for processing.
(5) Optical drives are divided into read-only optical drives (CD-ROM) and read-write optical drives (CD-R, CD-RW), also known as burners. Which is used for reading or storing large-capacity multimedia information.
[Edit this paragraph] Multimedia software
The operating system of multimedia computer must expand the functions of multimedia resource management and information processing on the original basis.
Multimedia editing tools include word processing software, drawing software, image processing software, animation software, audio editing software and video editing software.
The authoring tools of multimedia application software are used to help application developers improve their development efficiency. They are generally application generators, which organize various media materials in the form of hypertext nodes and chain structures to form multimedia application systems. Authorware, Director and multimedia reference books are all well-known multimedia creation tools.
[Edit this paragraph] Multimedia teaching
Teaching mode refers to a paradigm of teaching and learning to complete teaching tasks, which includes teaching mode, learning mode and related teaching strategies.
(1) classroom demonstration teaching mode (classroom explanation teaching mode) This teaching mode has two main ways in classroom teaching: teaching demonstration and simulation demonstration.
(2) Personalized teaching mode The multimedia courseware of personalized teaching mode generally includes: introduction, teaching control, encouragement, teaching information presentation, answering questions, answering diagnosis, answering feedback and remedy, and ending. There are two kinds of multimedia courseware corresponding to personalized teaching mode: multimedia teaching materials and teaching-assisted electronic reading materials.
(3) The problems involved in computer simulation teaching mode are: basic model, simulation presentation and performance, system response and feedback.
(4) Inquiry teaching mode Inquiry teaching mode generally consists of the following links: determining problems, creating teaching situations, inquiry learning, feedback and evaluation of learning effects. The main constraints are wandering and disorientation.
(5) Cooperative teaching mode
(6) Internet-based distance teaching mode
Multimedia computer teaching system
First, the hardware environment of multimedia computer teaching
(1) classroom demonstration classroom
(2) Network classroom
(3) Modern teaching resource center and electronic reading room.
(4) Campus network
Multimedia computer teaching software system
(1) Multimedia Material Making Software
Word processing: Notepad, WordPad, Word, WPS.
Graphic image processing: PhotoShop, CorelDraw, Freehand
Animation: AutoDesk Animator Pro, 3DS MAX, Maya, Flash.
Sound processing: Ulead Media Studio, Sound Forge, Cool Edit, Wave Edit.
Video processing: Ulead Media Studio, Adobe Premiere
(2) Creation tools
Programming languages: Visual Basic, Visual C++, Delphi.
Multimedia writing system: Authorware, Director, reference book, Flash.
(3) Multimedia computer teaching software
Various teaching courseware that can be used for classroom teaching, counseling and demonstration.