You need to be able to describe all of these techniques in the exam however to understand them I think is best to see them actually in use. So, read the descriptions and then look at the powerpoint.
Interlacing
This refers to images which when downloading do not download line by line but appear initially blurry and then become clearer. JPEG supports interlacing. GIF does not.
Dithering
This is a technique designed to make an image with a low colour depth appear to have a higher colour depth. It mixes pixels from areas of flat colour, together, giving the impression of more colours than are available.
Transparency
This is the extent to which a part of an image can be made “see through”. Very useful when images are being used together or on top of each other.
Anti-Aliasing
This is another technique to make a graphic appear to be of higher quality than it actually is. The jagged edges that can appear on the edge of a graphic are made to appear smoother by adding extra colours and pixels.
