Bitmap vs. Vector Images
There are two types of computer graphics...vector images and bitmap images.
Vector images are used
to define a line that has end points. The coordinates of where the straight line begins and ends are
computed without needing to define all the points in between. A rectangle might be defined as
follows: 125, 125, 300, 300. This means that the top left corner is at the coordinate 125 X 125
(125th pixel horizontally X 125th pixel vertically) and the bottom right corner is at 400 X 300
(400th pixel horizontally X 300th pixel vertically).
Vector images tend to be used for lines, boxes, circles, polygons and other graphic shapes that can
be mathetically expressed in coordinates on a computer screen. The program always references the
shape itself...not each individual pixel that makes up the shape.
There are two main advantages to vector images:
They require very little information (bits of data)...as with the example of a rectangle above.
The shapes can be moved or scaled (resized) and still maintain crisp, clear lines...even if they are
scaled to a very large size.
Bitmap Images are sometimes called "paint graphics." That's because bitmap images tend to be used
for photo-realistic images and for complex drawings requiring fine detail. A bitmap is simply a matrix of
pixels...or a "grid" of pixels. Each pixel used to create a shape or object in the image is referenced. You
edit groups of pixels instead of shapes (as in vector images).
The main advantage of bitmap images is:
They are able to accurately represent the wide range of colors and shades in complex images.
Adobe Photoshop creates images using bitmaps.
UP to the "Multimedia on the Internet" Class Home Page
For more information about this Web Site contact sanderso@cc.usu.edu
(Dr. Steve Anderson at Utah State University).