Multimedia technology is not a simple combination of various information media. It is an information technology that combines information in the form of words, graphics, images, animations and sounds, and is comprehensively processed and controlled by a computer, which can support a series of interactive operations. The development of multimedia technology has changed the application field of computers, which has changed computers from special products in offices and laboratories to ordinary tools in the information society, and has been widely used in industrial production management, school education, public information consultation, commercial advertisements, military command and training, and even family life and entertainment.
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.
1.2 file
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.
1.3 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.