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5 Multimedia

In modern society, information processing systems are being used in various fields. Among these, the system that has frequently been used recently is the multimedia system. The multimedia system is a system that uses multimedia data such as moving images, still images, sound, and text by integrating it on a computer and can be represented in various forms.

5 - 1 Multimedia Technology

5-1-1 Multimedia

Multimedia refers to interactive (i.e., bidirectional) media. Information, such as characters, images, pictures, and sound, is digitalized (i.e., encoded) to integrate information media. Different types of information available on the Internet that we use are registered on a Web server. (This is known as web content.) A large part of the web content is multimedia content in which characters, images, and sound are combined together. The software used for saving and managing the web content, and constructing a website is called CMS (Contents Management System). A typical CMS is Wiki by which the editing of a web page is performed easily from the browser. Wikipedia, which is called the encyclopedia of the Internet, is a typical usage example of Wiki. Links (i.e., information for accessing related pages) are embedded in a large part of the web content, and different types of information can be searched for by following the links. Web content that is correlated through a link including text information is called hypertext, and web content (i.e., multimedia content) that is correlated through a link including images is called hypermedia. In the authoring environment for creating the multimedia content, the software called multimedia authoring tool is mostly used. This software enables easy integration of material (i.e., files) such as documents, image/video, and sound through the mouse operation. At this time, PDF (Portable Document Format) may be used as one of the formats of document files. PDF is a format of document files developed by Adobe Systems that enables print images to be displayed in almost the same manner even in different applications by converting them into PDF files as they are, without any changes. When a print image is converted to a PDF file, the file size becomes smaller than the original data file, but editing cannot be performed in the original application. However, the characteristics of a PDF file also result in advantages such as prevention of data change and secondary use. Because of its property, the data files of multimedia have a larger size than the data files of only text information. Therefore, on the Internet, the technique called streaming is used for

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playing back at the download of a data file of video and music.