Routing techniques using serial neighborhood image analyzing system

A method of automatically laying out conductor paths between source and target areas on a circuit represented by an image containing pixels having preselected values associated with source, target, free and blocked areas of the circuit, said method comprising:

• (a) feeding the pixels of the image in a serial manner to an input of a neighborhood transformation stage, said stage including neighborhood extraction means for sequentially accessing each neighborhood of pixels in the image, the stage further including neighborhood transformation logic means, operative to selectively provide a transformation output for the stage as a function of the values of a center pixel and its surrounding neighbor pixels in each extracted neighborhood;
• (b) performing a grow out step using the neighborhood transformation logic means to transform free pixels in the image between the source and target to values associated with arrows pointing back towards the source;
• (c) performing a trace back step by changing the arrow pixels between the target and source to given values associated with a conductor path between the target and source;
• and
• (d) performing a clean up step by changing the conductor path pixels to values associated with blocked areas of the circuit thereby producing an image that may be utilized to lay out other conductors on the circuit.