There is provided a recognition system. The recognition system is coupled to an image capturing device, and determines a first matching percentage by comparing a first live image with a first reference image, determines a second matching percentage by comparing a second live image with the first reference image, compares the first matching percentage with the second matching percentage to determine a direction of adjustment of a setting of the image capturing device, and generates a feedback signal to adjust the setting based on the direction of adjustment. The first live image and second live image are captured by the image capturing device.