Definition and Review on Raster and Vector Graphics

Raster Graphics
Many images use raster graphics, such as images that are imported from your digital camera, and the internet. Raster images are made up of a grid of pixels, and these are also called bitmap. For raster images the larger the image the more disk space it will take up, as the size goes up the more pixels the image will have.

Raster Images can usually be scaled down with no loss of quality, but enlarging a raster image will cause it to look blocky, as the individual pixels will get enlarged and able to see pixel more clearly.

Example of a raster image enlarged:
Raster  images are best used for photographs, as you get great colour detail, but you can not enlarge, as the image will become blurry.

Basic file types for Raster Graphics:

• .jpg/jpeg
• .gif
• .png
• .tiff or .tif
• .psd
• .bmp

Vector Graphics
Unlike raster images that are made up of pixels, and use JPEGs, GIFs and BMP. Vector graphics are not made up of a grid of pixels, but instead these are comprised of paths, made from a start and end point. A path in a image can be a line, square, triangle, or a curvy shape. And with these paths are able to create simple to complex drawings.

As Vector images are not made from a certain amount of dots, they can easily be enlarged in size and not lose any quality. Unlike raster image that will look blurred and blocky. This is ideal for logos, as it can be used on a business card, and then can be scaled up to fit on larger surfaces. Many Flash animations also use vector graphics, since they scale better and typically take up less space than bitmap images.

Example of a vector image enlarged:
Vector images are best used for fonts/logos, as they have the ability to enlarge without losing quality, but this images have a limited colour detail.

Basic file types for Vector Graphics:

• .drw
• .pif
• .pct
• .ps
• .eps
• .svf
• .ai