A new hardware module for automated visual inspection based on a cellular automaton architecture

This paper presents the design and VLSI implementation of a new automated visual inspection system based on a cellular automaton architecture, suitable for circular object inspection. Cellular Automata (CA) transform the area of the object of interest into a number of evolution steps in the CA space. The proposed technique does not require the extraction of image features, such as boundary length and total area, which are computationally expensive in other methods. The die size dimensions of the chip, for a 16×16 pixel image, are 3.73 mm×3.09 mm=11.52 mm² and its maximum frequency of operation is 25 MHz. Experimental results using computer-generated images, as well as real images obtained and processed through a commercial vision system, showing the suitability of the proposed hardware module for detecting circular objects, are also presented. Targeted applications include inspection tasks (accept/reject operations) of circular objects, such as tablets in the pharmaceutical industry, and detection of uncoated areas, foreign objects and level of bake in the confectionery and food industry.