The Movement of the Cursor or the pointer movement is controlled by the mouse Types of Mouse: Mechanical: It contains a rubber or metal ball on its underside.it rolls in all directions. Opto mechanical: Optical sensors are used to detect motion of the ball. Optical: A laser is used to detect the mouse's movement. Cordless Mouse: It works by infrared or radio waves. Fig: A Computer Mouse 2.5: Keyboards A keyboard is an Input Device that has typewriter-like
This type of noise is caused due to noisy transmission channels, malfunctioning of camera sensors pixels. The affected noisy pixels can take only two values i.e. maximum and minimum in the dynamic range, giving the appearance of dark spots in the white region and white spots in the dark region of an image while the unaffected region remain unchanged