1. An apparatus for halftoning using an overlapping threshold array, said apparatus comprising: an input port for receiving data to be printed with halftones, the input port having an input and an output, the output of the input port coupled to a bus; a memory means for storing instructions and data, the memory means having an input and an output, the input and the output of the memory means coupled to the bus; a central processing unit (CPU) for processing data from the input port and memory means using instructions from the memory means to form a data stream representative of an image, the CPU having inputs and outputs coupled to a bus; a video processing unit having an input and an output for comparing the data stream from the CPU to a threshold array to produce pixel values, the input of the video processing unit coupled to the bus; an output device having an input for receiving pixel values from the video processing unit into an image, the output device producing the image in visible form, the input of the output device coupled to the output of the video processing unit; a FIFO buffer having an input and an output for storing the data stream used for forming the image, the input of the FIFO buffer coupled to the bus to receive data from the CPU, the output of the FIFO buffer coupled to the input of the video processing unit 34; a plurality of registers having an input, an engine output and a video output for storing engine and video processing unit control signals, the input of the registers coupled to the bus, and the video output coupled to the input to the video processing unit; and an engine control unit having an input and an output, for controlling the halftoning and the printing of the output device and controlling the video processing unit, the input of the engine control unit coupled to the engine output of the registers, and the output of the engine control unit coupled to the output device and the video processing unit.