One of the great things about computer graphics is that you can easily manipulate photographs and drawings to suit the size you need to them to be. Yet changing sizes can result in a deterioration of the image quality. Fortunately there are ways to minimize the distortion.
Images fall into two general categories called vector and bitmap. Vector images are formed from mathematical calculations, while Bitmap images consist of tiny dots called “pixels.” Vector images can be easily re-sized without losing much detail, but with bitmaps the changing ratio of pixels as you change size can affect image quality.
Vector images will re-size flawlessly as long as you keep the dimensions the same – to double the size double the already existing dimensions, always making sure the relationship between height and width is kept the same. The same careful consideration of size relations should be followed when altering bitmap sizes. Through filtering the computer will smooth over some of the flaws, but this becomes less effective if you try to increase a bitmap image beyond twice its original size. Therefore if major size changes are desired, it is usually best to get or transform your image into a vector format.