1. A method for determining whether a gesture is being performed in a sequence of source images, the method comprising: detecting the gesture in a reference image; selecting, from a plurality of gesture models, a first gesture model that most closely matches the detected gesture, the first gesture model including a composite of images that include gestures having a same type of gesture as the detected gesture; scanning the sequence of source images using the first gesture model without using another gesture model to determine whether the gesture is being performed, the sequence of source images including a plurality of images obtained after the reference image, wherein scanning the sequence of source images includes comparing a source image obtained after the reference image with the first gesture model to determine whether the gesture is performed in the source image; and ending scanning of the sequence of source images using the first gesture model without using another gesture model of the plurality of gesture models to determine whether the gesture is being performed if using the first gesture model to scan the sequence of images to determine whether the gesture is being performed results in a determination that the gesture is being performed.