Sampling Rate Conclusion Introduction Tristimulus Theory is a fancy name for a well established method of measuring color. According to the theory, the human eye has tiny light-sensitive sensors in the retina called rods and cones .
Rods are sensors that detect brightness and darkness, and cones are sensors that detect colors.
The theory also suggests that cones in the human retina have peak sensitivity to red, green, and blue frequencies, and that all other colors visible to the human eye can be represented as combinations of these three primary colors. Rods detect the areas of brightness and darkness within the first three images, and cones distinguish the difference between the images as red, green, and blue. This theory of color perception is very useful for film, video, and computer graphics because it allows any color visible to the human eye to be represented as some particular combination of red, green, and blue primaries. This method of representing color is known as RGB . There are several different methods of transmitting color information in a video signal.