A METHOD AND A SYSTEM FOR DETECTING THE PRESENCE OF AN IMPEDIMENT ON A LENS OF AN IMAGE CAPTURE DEVICE TO LIGHT PASSING THROUGH THE LENS OF AN IMAGE CAPTURE DEVICE

摘要

A method for detecting the presence of dirt on the lens of a camera (3) comprises passing image data of sequentially captured images through a high pass filter (20) for detecting predefined areas (11) in the captured image frames (10), the image data of which is indicative of an area of low or no high spatial frequency content, which could possibly be as a result of dirt on the lens. The locations of the predefined areas (11 ) in which the image data thereof is indicative of an area of low or no high spatial frequency content in the currently captured image frame is stored in memory (23), for comparison with the next captured image frame. The locations of the predefined areas 11, the image data of which is indicative of an area of low or no high spatial frequency content which coincide in the captured image frames are determined as being predefined areas (11 ) of which the image data is indicative of dirt on the lens of the camera (3).