ABSTRACT
RGB A ‘full colour’ image can be assembled from the three primary colours of light; red, green and blue or ‘RGB’. All the colours of the visible spectrum can be created by varying the relative amounts of red, green and blue light. The information for each of the three primary colours in the RGB image is separated into ‘channels’. Each channel in an RGB image is usually divided into 256 levels. An RGB colour image with 256 levels per channel has the ability to assign any one of 16.7 million different colours to a single pixel (256 x 256 x 256). Colour images are usually captured or scanned in the RGB ‘colour mode’ and these colours are the same colours used to view the images on a computer monitor. A colour pixel can be described by the levels of red, green and blue, e.g. a red pixel may have values of Red 255, Green 0 and Blue 0; a yellow pixel may have values of Red 255, Green 255 and Blue 0 (mixing red and green light creates yellow); and a grey pixel may have values of Red 127, Green 127 and Blue 127.
