File Types - Graphics
Types of Graphics
There are TWO main types of graphics:
Vector graphics: use mathematical algorithms to draw lines and curves that can be combined to create an image from geometric objects such as circles and polygons. These usually have a smooth finish.
Bitmap (Raster) Graphics: Bitmap (or raster) images are stored as a series of tiny dots called pixels. Each pixel is actually a very small square that is assigned a colour, and then arranged in a pattern to form the image.
There are TWO main types of graphics:
Vector graphics: use mathematical algorithms to draw lines and curves that can be combined to create an image from geometric objects such as circles and polygons. These usually have a smooth finish.
Bitmap (Raster) Graphics: Bitmap (or raster) images are stored as a series of tiny dots called pixels. Each pixel is actually a very small square that is assigned a colour, and then arranged in a pattern to form the image.
Pixel = (A word invented from "picture element") is the basic unit of programmable colour on a computer display/ image.
Bitmap images are good for images that need to show great detail, as it offer 1000s of colour gradations. Unfortunately, due to the use of pixels, the image pixelates when enlarged (As shown in the image below).
Due to Vector’s being made from mathematical algorithms, the file size is smaller than a typical bitmap image. As they don’t have 1000s of pixel to remember, just a few algorithms.
Vector graphics do not pixelate when enlarged (easily scaled). Vector images are best used for graphics that required limited colours (e.g. logos and text). However, Vector image files are not well supported on the web, due to varied browser types. This is because different systems have dissimilar (and possibly incompatible) vector formats. Hence, vector images often rasterized – turned into raster/bitmap images – before uploading, which usually increases the overall file size.
Bitmap images are good for images that need to show great detail, as it offer 1000s of colour gradations. Unfortunately, due to the use of pixels, the image pixelates when enlarged (As shown in the image below).
Due to Vector’s being made from mathematical algorithms, the file size is smaller than a typical bitmap image. As they don’t have 1000s of pixel to remember, just a few algorithms.
Vector graphics do not pixelate when enlarged (easily scaled). Vector images are best used for graphics that required limited colours (e.g. logos and text). However, Vector image files are not well supported on the web, due to varied browser types. This is because different systems have dissimilar (and possibly incompatible) vector formats. Hence, vector images often rasterized – turned into raster/bitmap images – before uploading, which usually increases the overall file size.
Activity 1
Answer the following questions:
- Compare Vector and Bitmap/Raster images. Where might you use each type in your multimedia projects? (Pg. 220)
- What is a raster image? (Pg. 221)
- What is RGB, CMYK and Bit Depth (Pg.224-225)
- Why are we more concerned with Display Resolution and Bandwidth than Print Resolution? (Pg.227)
- What is the standard PPI for video and web? Why is it a waste of time to go any higher than this on a computer or TV monitor? (Pg.227)
- What is Anti-alisasing? (Pg.228-230)
- What is compression? What are the two basic types of compression? (Pg. 230-231)
- How are Vector graphics created? (Pg.233-234)