Kotebe Metropolitan University Computer Science Technology Department Multimedia

Kotebe Metropolitan University Computer Science & Technology Department Multimedia (Co. Sc 4151) Chapter One : Introduction to Multimedia

Outlines 1. 1. What is Multimedia? 1. 2. Multimedia and Hypermedia 1. 3. Characteristics of multimedia 1. 4. Types of multimedia 1. 5. Application of multimedia 1. 6. Elements of Multimedia 1. 7. Multimedia Database (MMDB) 1. 8. Compression Algorithms 2

1. 1 What is multimedia? n Multimedia is a combination of two words n n Multi meaning many Media meaning to communicate Multimedia means using different Medias to Communicate What to communicate? n Concept/message n Commercial n Short films n Publishing a book n Develop a web site 3

1. 1 What is multimedia …. n n n Multimedia is the field concerned with the computer controlled integration of text, graphics, drawings, still and moving images (Video), animation, audio, and any other media where every type of information can be represented, stored, transmitted and processed digitally. Multimedia can be defined as the integration of multiple forms of media. It includes the combination of text, music, pictures, drawings, moving images (animation), video to create some applications. Multimedia concerns the representation of mixed modes of information. 4

1. 2 What is hypertext and hypermedia? n n n Hypertext is a text which contains links to other texts. Hypermedia is not constrained to be text-based. It can include other media, e. g. , graphics, images, and especially the continuous media – sound and video. Example Hypermedia Applications 5

What is hypertext and hypermedia? n The World Wide Web (WWW) is the best example of a hypermedia application. n Power point n Adobe Acrobat (or other PDF software) n Adobe Flash n Many Others? 6

Multimedia systems n A Multimedia System is a system capable of processing multimedia data and applications. n A Multimedia System is characterized by the processing, storage, generation, manipulation and interpretation (or rendition) of Multimedia information. 7

1. 3 Characteristics of multimedia n A Multimedia system has four basic characteristics: n Multimedia systems must be computer controlled. n Multimedia systems are integrated. n The information they handle must be represented digitally. n The interface to the final presentation of media is usually interactive. 8

1. 4 Types of multimedia Multimedia can classified in to Static n Static multimedia is time independent discrete value Information in these media consists exclusively of a sequence of individual elements without a time component. Example: n n Text Graphics Images 9

Types of multimedia… Dynamic n Dynamic media is time dependent continuous media. Information is expressed as not only of its individual value, but also by the time of its occurrence. Example n Audio n Video n Animation 10

1. 5 Application of multimedia n n n n Hypermedia courseware Video conferencing Video on demand/IPTV Interactive TV Advertisements Education animation films 11

Application of multimedia… n n n n computer & TV games advertisements designing education Games simulation (virtual reality) defense applications graphics applications 12

1. 6 Elements of multimedia n The following are the most common elements of multimedia n n n Text Graphics Images Audio Video Animation 13

Elements of multimedia n Text n n Text is the most common medium in multimedia. We can use colors, formats, sounds, animation for the text to make more effective and attractive to the users. We can use different formatting options from the tool bars to manipulate the text. We can add objects like clip arts, word arts, pictures to our presentation. We can drag, resize, and overlap the objects as per our requirement. 14

Elements of multimedia… Image n An image from Latin Imago is an artifact, for example a two dimensional picture that has a similar appearance to some subject-usually a physical object or a person. n A digital image is a presentation of a two-dimensional image using ones and zeros (binary). Depending on whether or not the image resolution is fixed, it may be of vector or raster type. Without qualifications, the term “digital image” usually refers to raster images also called bitmap images. 15

Elements of multimedia… Graphics from Greek graphikos are visual presentations from some surface, such as a wall, canvas, computer screen, paper, or stone to brand, inform, illustrate or entertain Examples are n Drawings, line art, graphs, diagrams, typography, symbols, geometric, maps, engineering drawings or other images. n n Graphics always combine text, illustration, and color. Graphics design may consist of the deliberate selection, creation, or arrangement of typography alone, as in a brochure , flier, poster, website, or book without any other element. 16

Elements of multimedia… Animation n n n Animation: Animation means moving of an image. Animations are created from series of individual images called ‘frames’ When individual frames are moving rapidly in sequence, we feel that the image is moving. Music (sound) is always stored in computers in digital format. Sounds can be used in multimedia for background music, sound effects, narration (explanation). Appropriate sound effects make any animation more interesting and more believable. 17

Elements of multimedia… Video n Commonly refers to several storage formats, it may include text, image, sound etc. 18

1. 7 Multimedia database (MMDB) n Multimedia databases are a collection of related multimedia data. The multimedia data include one or more primary media data types such as text, images, graphics objects (including drawing, sketches and illustrations), animation sequences, audio and video. 19

Application areas of MMDB n Examples of multimedia database application areas n Digital libraries n News-on-demand n Video-on-demand n Music database n Geographic Information system (GIS) n Telemedicine 20

Multimedia Database Management System(MMDBMS) n Multimedia database management system is a framework that manages different types of data potentially represented in a wide diversity of formats in a wide array of media resources. It provides support for multimedia data types, and facilitate for creation, storage, access, query and control of a multimedia databases. 21

1. 8 Compression Algorithms n n n Compression algorithms re-encode image data into more compact representations of the same information. Think of compression as using fewer words to say the same thing. Compression Methods There are basically two types of compression methods: lossy and lossless. Lossy compression creates smaller files by discarding (losing) some information about the original image. It removes details and color changes it deems too small for the human eye to differentiate. Lossless compression, on the other hand, never discards any information about the original file. 22

Home Study 1. 2. 3. 4. 5. 6. 7. Write the difference between hypertext and hypermedia List three examples of dynamic media List three application areas of Multimedia database Explain purpose and techniques of compression Volume of multimedia data contributed by social media. Read about the concept of entropy in any field you want Explain the difference and give example v v v Single media and multimedia Sound audio Image and graphics Animation and video Raster image and vector image Text based retrieval and Content based retrieval 23