❖All of the colours that humans perceive can be created by mixing the three additive primary colours: red, green and blue. Human vision is a system that is able to detect these three wavelengths or ‘bands’. Our brains combine this data detected by our eyes into a single colour image. This is also the basis of colour imaging.
Colour images are actually made up of three values, one each for the amount of red, green and blue light that entered the camera for each pixel. This means a ‘3-band’ image is needed to display a colour image.
❖RGB (red, green, and blue) refers to a system for representing the colors to be used on a computer display. Red, green, and blue can be combined in various proportions to obtain any color in the visible spectrum. Levels of R, G, and B can each range from 0 to 100 percent of full intensity. Each level is represented by the range of decimal numbers from 0 to 255 (256 levels for each color).