The word multimedia is made up of two separate words, multi meaning many and media meaning ways by which information can be transmitted. Therefore, multimedia can be described as the integration of multiple media elements together to influence the given information so that it can be presented in an attractive and interactive manner. In simple words, multimedia means being able to communicate in more than one way. Traditionally, information is presented in only one medium, be it newspaper, radio or television. With the development of computers, the presentation of data took on a whole new meaning. Multimedia is a computerized method of presenting information by combining audio, video, graphics, text, and/or animation components. For example, a multimedia database for musical instruments may allow a user not only to search and retrieve text for a particular instrument, but also to view its pictures and perform a piece of music. The advent of high resolution screens and audio and video playback facilities for computers has led to increased use of multimedia applications.
A typical multimedia application is characterized by some characteristics which are as follows:
· Use of digital technologies
· Requires user interaction
· Integrates sound, images, text and data into seamless applications.
As we know, multimedia is mainly concerned with computer-controlled integration of text, graphics, drawings, still or moving images (video), animation and audio, where any type of information can be represented, stored, transmitted and processed digitally. The various elements that together make up multimedia are as follows:
Text
Displaying words on the screen, that is, text, is the basis of most applications. Humanity developed text and symbols in order to communicate. Writing helped man to remember things for a much longer period than what is possible with the help of memory (brain). Words and symbols in any form, spoken or written, are the most common means of communication. Nowadays, text can not only display information, but has also acquired interactivity; things like electronic annotation that helps navigate through all the information presented on the web via hypertext. Hypertext can be defined as an object in the text that allows the user to jump from one web page to another with a single click of the mouse button. It acts like electronic footnotes and helps in navigating through all the information. Files can contain plain text or formatted text. For example, hypertext markup language (HTML), source programming language (C, Pascal) or rich text format (RTF) – a file format for text files that includes formatting such as different font styles and fonts, etc. Basic text storage is 1 byte per character (text or format character). For other forms of data, such as spreadsheet files, some may store the format as text (with formatting), others may use binary encoding. The text can be written using various editing and word processing tools such as word processing software such as Microsoft Word and Word Perfect where the text file can be developed and later imported into the multimedia creation tools to integrates with other media elements.
Graphics
It is a general term used to describe a pictorial representation of data. When we talk about graphics, we usually mean those pictorial images that are created from primitive objects such as lines, polygons, circles, curves and arcs. For example, a picture of a cube can be drawn using lines, and a pie chart can be drawn using lines and arcs. Images are still images that are represented as a bitmap (a grid of pixels), but graphics can usually be edited or revised (unlike images). Graphical input devices typically include a keyboard, mouse, trackball, or light pens. They say a picture is worth a thousand words, so adding a graphic element to a text document can change the user’s perception of the document. Integrating the widget into the app makes it more elegant and understandable. Evolving technology has created an abundance of graphics and visuals for a multimedia project. For the development of a multimedia project, various images are captured from various sources such as scanners, digital cameras and via the Internet. Once the images are transformed into digitized form, they can be edited and modified using image editing software, namely Adobe Photoshop, Corel Draw and Freehand.
audio
It means the sensation resulting from stimulation of the auditory mechanism by air waves or vibrations. It is the vibration of air molecules in the atmosphere that can be felt by the ear. This involves the transmission of mechanical vibrations from an elastic medium that can be detected by the human ear. Computers and digital technology have changed the face of the music industry. Today, digital music is used to create special effects in television, movies, in recording studios, and in games. Music and sound effects not only add interactivity to the user but also play with the user’s perception and emotions. Audio can also be used to provide a sense of place or mood, as done to perfection in the game. Music is perhaps the most obvious form of sound. It can be used to create a mood, convey an idea and even tell a story. Speech is also a perfect way to teach users how to pronounce words, as done by speech learning software. Non-speech sound effects can be used in the user interface to inform users of background events. For example, the sound of a file downloading progress can be signaled by the sound of water pouring into a glass that is gradually filling. These types of background sounds should be unobtrusive. In addition, sounds can be embedded in a web page and played.
Video
Refers to a moving picture accompanied by sound, such as a film on television. It is a medium that is as direct as print and attracts more attention. It adds richness to the content and enhances the user experience. It dramatizes and adds impact to the multimedia application. Integrating a video element into a multimedia application provides a lot of information in a short amount of time. If used in a planned and well-executed way, it can make dramatic differences in multimedia performance. Digital video is useful in multimedia applications for displaying real-life objects, such as people talking or real illustrations of concepts. Video places the highest performance demands on computer memory and bandwidth if placed on the Internet. Regarding computers and the Internet, the main problems with most videos are that their production quality is too low and they have a very large file size. To make video usable, video files must be compressed into different file formats.
Animation
It is the process of arranging still images in rapid succession to create the effect of live motion. The sequence of images is displayed one after the other very quickly, so the human eye and brain blend the images to create the effect of motion. It is a powerful tool capable of communicating complex ideas. It is often much easier to show someone how things work than to try to explain it. Animation is viable because of a natural phenomenon known as constancy of vision. An object seen by the human eye remains mapped on the retina of the eye for a short time interval after viewing. This makes it possible for a series of images that change very slightly and very quickly, one after the other, to seemingly merge into a visual illusion of movement. In other words, if one simply slightly changes the location or shape of an object quickly enough, the eye will perceive the changes as motion. An animated sequence must display a certain number of frames every second. For professional animation, you should have at least 30 frames per second.
In today’s challenging world, if the ideas of the presentation are not expressed in an effective manner, then the presentation is a failure. One way to express imaginative ideas is through the use of graphics. Graphs can be presented in different modes, which are described below:
· Background: Sets the tone and theme of the presentation. It should be based on the type of information to be conveyed. For example, if the information is more text oriented, then simple background images should be used. In case the information is to be conveyed to young children, then the background should be more animated and colorful.
· Two-Dimensional (2D) Graphics: Usually, when a person looks at a computer screen, he/she is in a two-dimensional image. The image extends from left to right and top to bottom, but usually not in and out of the computer screen. The definition of a 2D image only contains information about how a scene looks from a certain point.
· Three-dimensional (3D) graphics: A 3D image contains scene information in three dimensions (x, y, and z coordinates). However, this 3D data cannot be viewed directly. To see it, the 3D data must first be converted into a 2D image by the computer through a process known as rendering. The rendering process takes as input the 3D scene and camera location and attributes, and produces as output the 2D image that the camera sees from that particular point in space. The process is done by mathematically projecting a 3D scene onto a 2D surface. In photography, this is done by the camera lens, but in computer graphics, it is done by solving mathematical equations. In both cases, the result is a 2D image that was generated from a 3D scene.
· Charts and graphs: In multimedia projects related to business and learning, charts and graphs are the most appropriate forms of graphics used to present information related to facts and figures.
· Flow charts: The use of flow charts expresses the systematic order of an event. They were developed mainly to break the complex steps of solving problems into smaller, less complex steps so that developing logic becomes easier. They are also used to represent 2D graphics.