Image thinning process

Abstract From the Canadian patent

A process for thinning an image, comprising the steps of defining an image in terms of a plurality of discrete picture elements (pixels), convolving each horizontal string of pixels of the image with itself shifted a predetermined number of pixels, weighting each shifted position of each horizontal string, selecting certain of the pixels of the weighted horizontally convolved pixel strings which correspond to predetermined descriptors, convolving each vertical string of pixels of the image with itself shifted a predetermined number of pixels, weighting each shifted position of each vertical string, selecting certain of the pixels of the weighted vertically convolved pixel strings which …