Patent ID: 7609857

Claim:
A method for recognizing a visual obstruction using an image sensor associated with a vehicle, comprising: recording an image by the image sensor, wherein the image sensor is focused on an external region beyond the vehicle such that a visual obstruction on the vehicle is imaged; analyzing the image recorded by the image sensor, wherein at least one of a presence and a type of a visual obstruction is determined by the analysis of the image, wherein the analysis includes measuring a blurriness of at least a portion of the image; producing a signal which indicates one of the presence and the type of the visual obstruction; and controlling downstream systems based on the signal; wherein an analysis of at least one image recorded after an initial wiping operation on a windshield of a motor vehicle is used to determine whether to initiate a next wiping operation, and wherein the determination regarding the next wiping operation is based on blurriness of a first image that was recorded immediately after the initial wiping operation in comparison to blurriness of an image recorded subsequent to the first image.