A method for improving the driver assistance function, in particular of driver assistance systems based on video images recorded from a vehicle, and a corresponding device for that purpose made up of a camera and processing unit. To improve the function during rain, the passing of a windshield wiper through the camera image be used to classify individual images and/or portions of images as being of higher or lower quality, in order to improve the quality of the images from the camera. The images from camera are intended to be used for automatic driver assistance systems.