Color segmentation and figure-ground segregation of natural images

To recognize the objects in an image and to understand the image content, a computer system has to first separate the foreground objects from the background. Image segmentation and figure-ground segregation are, therefore, essential for computer image understanding. This paper describes a system called OLAG (Object-LAyer Grouping) for image segmentation and figure-ground segregation. OLAG consists of several incremental refinement steps which use colour and other visual cues such as size and compactness for grouping the image pixels. It produces, as an end result, a set of layers each containing an object or object part. Figure and ground relationships among the objects are inferred, giving their relative depths. It is shown that interesting and useful segmentation results can be obtained from the system.