METHOD AND APPARATUS FOR SEPARATING FOREGROUND FROM BACKGROUND IN IMAGES CONTAINING TEXT

A method and apparatus for thresholding gray-scale images containing text as foreground and dirt, colors, noise and the like as background. The method is adaptive in nature and can successfully separate a wide variety of text fonts and sizes, whether printed, typewritten, or handwritten, from the image background. The method uses multiple sets of thresholding process parameters in a contrast-based histogram evaluation to produce multiple candidate thresholded binary images. The method automatically selects the highest quality binary image, that is, the binary image that best represents text in the foreground, from among the multiple candidate binary images. The apparatus for implementing the method is a pipeline processor for highest speed.