Image thresholding system

摘要

An image thresholding system employing a ROM look up table to make threshold decisions. A plurality of shift registers are used to convert a digital pixel input which includes the pixel to be processed to an address for use in addressing the ROM look up table to provide a thresholded value for the pixel being processed. The output of the ROM look up table is utilized, together with other pixels from the pixel input, to address a second ROM look up table to provide a further refined threshold decision.