Mask extraction from optical images of VLSI circuits

This paper explores line labeling algorithms for extracting the mask layers from an optical image of a VLSI chip. We first create a suitable world model for VLSI images. Next, we introduce representation schemes for object features, together with the natural constraints these features satisfy. This label set is an extension of Huffman, Clowes, and Kanade´s label sets. Finally, we show how to interpret VLSI scenes by using a constrained labeling strategy. Performance of our labeling algorithms is demonstrated on some simple but representative simulated images of CMOS logic gates.