Chapter 2 _ Graphics and Images

Course: Multimedia Technology

Chapter: 2

Chapter Title: Graphics and Images

Contents:

• Introduction
• Bitmap Images
• Vector Images
• Image Resolution  & Aspect Ratio
• Image Data Types
• 1.Monochrome/ 1-Bit Images
  2.8-bit Gray-scale Images
  3.8-bit Colour Images
  4.24-bit Colour Images
  5.32-bit Colour Images

GRAPHICAL IMAGES

Graphical images obviously play a very important role in multimedia piece. Images may be photograph-like bitmaps, vector-based drawings, or 3D rendering. Tools for image management focus on different kinds of images and converting between formats peculiar to different tools and platforms

Bitmap Images

A bitmap is a matrix describing the individual dots that are the smallest elements (pixels) of resolution on a computer screen or printer or we can say a bitmap image is an array of logical pixels.

• monochrome just requires one bit per pixel, representing black or white
• 8 bits per pixel allows 256 distinct colors, 16 bits per pixel represents 32K distinct colors, 24 bits per pixel allows millions of colors

VECTOR IMAGES

A vector-drawn image is created from geometric objects such as lines, rectangles, ovals, polygons using mathematical formulas

Mathematical description of lines, curves and shapes. Requires computation to determine logical pixels Compact, scalable, resolution independent and easy to edit. Based on co-ordinates and algorithms. Description is infinitely thin Computation chooses logical pixels. Anti-aliasing to fix jaggies Basic blocks
Squares, polygons, ellipses, lines, bézier curves…
Easy to manipulate Scale, skew, rotate…

IMAGE RESOLUTION: 

Image resolution refers to the number of pixels per inch area of an image. Higher the resolution, means higher the number of pixels in that image hence better the quality but also with increase in file size. Lower  the resolution means less amount of pixels in an image and hence having poor quality with less file size.

Mirror Download Link:
 https://sites.google.com/site/drzeeshanacademy/multimedia-technology

Chapter 2_ Graphic Images