Date - 21/11/2013

Level 3 IT Course - Central Sussex College

Unit 35 Digital Graphics For Interactive Media

Task: Definition Of Raster and Vector Graphics

Raster Graphics

In today's world you will come across a lot of images either on the internet, magazines, books or other media where yo may find images. However when you look at a picture it is not just a picture and what I am tying to say is that pictures you see maybe made of billions of pixels and this is what the word 'Raster' is all about. For instance if you where to copy a paste from the internet into 'Paint' you can zoom in and you will see that the image or picture is made up of pixels. The word 'Pixels' is also known as 'Bitmap' which is the most common word used in graphics unless you are using a program such as 'Photoshop' and then you find the word 'Pixels'. When you edit the 'Screen Resolution' on your computer you will come across such resolutions as '640 x 480' and this means that you can only use up to a certain amount of 'Pixels' with this resolution. The biggest problem with 'Raster Images' is that they require a lot of memory to run and store however there are certain 'Formats' which can compress these images down:

JPEG (Joint Photographic Experts Group) or GIF (Graphics Interchange Format)

The other type is 'Vector Graphics'

'Vector Graphics' are not made of of billions of pixels however in fact 'Vector Graphics' start with a beginning and an end. A simple line can be known as a 'Path' which is commonly known in most software such as 'Photoshop' where you are most likely to draw in 'Paths'. 'Vector Graphics' can be resized without the image being distorted this makes 'Vector Graphics' ideal for 'Logos' because they can be altered to any size and still look good. Vectors use 'Points', 'Curves' and 'Angles' which make this type of 'Graphics' useful for drawing 'Diagrams' and 'Technical Drawings' such as plans for an 'Aircraft' or something. You are mostly going to use and find 'Vector Graphics' in software such as 'Adobe Illustrator' or 'Macromedia Freehand'.

Examples of 'Raster' and 'Vector' Graphics:

In the 'Raster Example' you can clearly see the 'Building Blocks' that make up the image and in the 'Vector Example' you can clearly see that the image is more flowing and there are no blocks (it looks more elegant and nicer).

On a personal not I have only ever used 'Raster Graphics' because I have worked with images in paint and plus I have done drawings in paint as well. I have only just come across 'Vector Graphics' when drawing in 'Photoshop CS 5'