Define multimedia
refers to computer-based presentation software that integrate at least two or more these elements:
- text
- audio
- graphic
- video
- animation
Define text
character to create word, sentences and paragraph
Define graphic
digital presentation of non-text information
Define audio
speech, music or any sound
- computer convert analog soundwave to digital format
Define animation
simulation of movement by displaying series of illustrations in form of frames
Define video
photographic images that display at speed 15 to 30 frames per second
2 types of text
Serif: with flag (Times New Romance)
San-serif: without flag (Arial)
2 types of graphic
Bitmap:
- formed from matrix of pixels with different colours
- defined by their dimension and number of colours they represent
Vector:
- composed of key points and paths, which define the shape and colouring instructions
disadvantages of Bitmap
- When enlarge,
- the graphic appear blocky
- software need to guess where to put the new pixels
When reduce,
- software need to decide which pixels to throw out - large files size
Format of Bitmap
- JPEG
- GIF
- PNG
3 advantages of vector
- small file size
- reusability: easily resized and reshape
- not restricted by rectangular shape
2 graphic compression technique
Lossy Compression
- remove unnecessary image details
Lossless Compression
- read horizontally from left to right, row by row
- compress the data
- GIF and PNG
Anti-aliasing technique
- smoothing jagged edges
- create non-solid colour blends
sampling
process of recording sound to pc
unit to measure quality of audio
Bitrate
- amount of digital information being stored per second of audio
2 types of audio
- streaming (Quick Time, Window Media)
- non-streaming (WAV, MIDI, MP3)
how video compression works
- only small portion of image change from frame to frame
- store the first reference frame
- assume the following frame are almost identical
- store only the changes between the frames
Multimedia application
- VR
- Web-based Training
- Distance learning
- Computer-based Training
multimedia authorizing software
- allow user to combined 5 elements into an application
- design screen to create interactivity
- Exp. Toolbook and Director
Multimedia Equipment
- sound card
- speaker
- digital camera
- video display
Interactive multimedia
a multimedia application that accept input from users and perform some action as response
