Near-sensor image processing (NSIP) is a new approach to low-level image processing in which the ability to perform global operations is crucial. We define a 2-D global logic unit (GLU), which consists of simple logical circuits arranged in a regular net, and describe how to perform powerful segmentation and feature-extracting operations using this net. Typical segmentation operations performed by the net are hole filling, smallest circumscribing rectangle, thresholding with hysteresis, and arbitrary propagation patterns. We describe how to obtain features like the position of an object in the image. Finally, we show that the NSIP concept, including the global functions, can be implemented in a single chip using today's VLSI technology.