COM111 Lecture Schedule 6

COM111 Lecture Schedule 6

Introduction to Multimedia, Building Blocks of Multimedia, Multimedia Systems, Multimedia Applications, Virtual Reality, Current Trends in System and Application software.

What is Media?

Media is the storage and transmission tools used to store and deliver information. Media can be called the vehicle which transports information. This is where the term medium of communications derives from.

What is multimedia?

Multimedia is the communication of ideas using multiple forms of information content (media). Multimedia means that computer information can be represented through audio, video, and animation in addition to traditional media (i.e., text, graphics/drawings, images).

Multimedia features:

• Possesses and makes use of different media
• Uses digital technology
• Demands interaction from the user
• Integrates sound, images, text and data into flawless applications

Building Blocks of Multimedia:

• Text
• Graphics
• Audio
• Video
• Animation

Text:

Text is one of the most important elements of multimedia. The standard document format used for Web pages is called HTML. A hypertext system enables the user to navigate through text in a non-linear way. Text written using various text editing and processing tools. Eg : Word processing software , MS Word.

Graphics :

      Image is a spatial representation of an object or a scene. (image of a person, place, object) Graphic is a broader and general definition which includes:

Ø  Pictures or Photographs

Ø  Drawings or Line arts

Ø  Clip arts

Ø  Buttons and Banner

Ø  Charts and graphs

Ø  Backgrounds

Ø  Icons

 Picture Vs Graphics / Image:

Pictures are found in the world which is external to the computers. Images are the 2-Dimensional digital representations of pictures found in computers. Computer attempts to duplicate the “look and feel” of a picture via storing and processing. An image is a “realistic” version of the original picture ; dependent on the quality and capabilities of the computer while  graphic, artist’s ability to use the software.

Modes of Graphics presentation:

• Background : it sets the quality and theme of presentation
• 2D Graphics: image spans from left to right and the image we see on the monitor is 2D image
• 3D Graphics: projecting 3D image on 2D surface
• Charts and graphs: appropriate forms of graphics used for presenting facts and figures related information
• Flowcharts : systematic order of  an event

Audio:

In multimedia production, sound and music are crucial in helping to establish a pleasant working  environments

Common types of sound format :

MIDI (Musical Instrument Digital Interface)

Sound files stored on a computer & contain musical notes, info sent via MIDI interface.

WAV (WAVe form audio format sound)

Microsoft standard file format Sound files storing waveform audio data(Universal files). Users use these files through QuickTime and windows media player and after recording produce the desired o/p using sound-editing software.

Audio on PCs :

  Many types of sounds are accessible with a PC. They include:

ú  Music

ú  Sound effects

ú  Spoken narration

ú  Video soundtracks

ú  Real-time telephone conversations

ú  Operating system alerts and prompts

Video :

Moving pictures accompanied by sound. Digital video is useful in multimedia applications for showing real life objects Video places highest performance demand on computer memory and on bandwidth if place on internet

Three main types of video file : 1)QuickTime 2)AVI (Audio Video Interleave) 3)MPEG (Moving Picture Experts Group)

Animation:

Animation is the Process of sequencing still images in rapid succession to give the effect of live motion Sequence of images shown one after the other very quickly – human eye and brain blend images to produce the effect of motion. Powerful tool capable of communicating complex ideas when location or shape of the object is changed rapidly the eye will perceive the changes as motion. Animations can be done in two ways:

·         2D animation: flat images are drawn one after the other, eg. Cartoons

·         3D animation: mathematical model of 3D objects is created to portray its width, height and depth, eg. CAD

Kinematics – study of movement and motion of structures that have joints, walking person.

Morphing – transformation of one image into another.

Multimedia system:

System capable of processing multimedia data and application Hardware & software play a vital role in supporting multimedia based application. Vast amount of data is required processing of multimedia elements, faster processor speed and supporting RAM is essential. Many multimedia products require storage on a CD-ROM.

Data compression:

To reduce the storage space – multimedia components must be compressed .The processes of cutting down the size of the file by special compression algorithms. Two types of compression:

• Loss: few data discarded to achieve massive reductions in size, e.g. JPEG & MPEG images.
• Lossless: size is reduced without discarding any information of the original data, e.g. PNG, ZIP tool for text compression.

Multimedia applications:

• Multimedia in education
• Multimedia and entertainment
• Multimedia and training
• Multimedia in business
• Multimedia  interactive Kiosks

Virtual Reality:

Artificial environment created by using special computer hardware & software presented to the user that appears and feels like a real 3D world. To enter into virtual reality user wears special glove, earphones & head-mounted display device (HMD). Virtual reality systems require very expensive hardware & software and confined to research laboratories.