METHOD AND APPARATUS FOR BACKGROUND DETERMINATION AND SUBTRACTION FOR A MONOCULAR VISION SYSTEM

摘要

A method and apparatus for producing a background image from a plurality of images of a scene and for subtracting a background image from an input image are described. A background image is produced by dividing an image (40) into subimages (42), acquiring reference subimages (48) for each subimage location and comparing subsequent subimages with the reference subimage to determine if any objects have passed between the reference subimage and the video camera (22) that acquired images. When objects have passed between the reference subimage and the video camera (22), the reference subimage is designated as background and stored in a background image (50). Background portions of an input image can be removed or their intensity diminished with a background image. Foreground weights can be determined by comparing the difference between a background image and an input image. To the extent that corresponding pixels are the same, the pixel is given a low foreground weight, indicating that the pixel is a background weight. The background subtraction method can further employ a weighting curve (70) to take into account noise considerations. The foreground weights are then applied to an input image to diminish or remove pixels in the background.