The RGB color model is an additive color model in which red, green, and blue light is added together in various ways to
reproduce a broad array of colors. The color model is the industry color standard. As one of the most widely used color
system, it almost involves all the colors perceived by human vision.
In order to eliminate the impact of ambient light to optical flow calculation, the N.Ohta advance a calculating model
based on gray color constant. The model assumes that the color image is composed of the three separate RGB gray images.
Calculating the optical flow of each point in the three separate RGB gray images can be described as follows