Method of filtering an image for high precision machine vision metrology

A method for inspecting a workpiece feature that is proximate to an occluding feature in a workpiece image acquired by a machine vision inspection system, the machine vision inspection system having a user interface that is used to define a sequence of operations that are used to inspect the workpiece image, the machine vision system being utilized to perform the method, the method comprising:

• acquiring a first workpiece image;
• choosing a shape of a structuring element based on the shape of the workpiece feature to be inspected in the workpiece image, such that the shape of the structuring element is similar to the shape of at least a portion of the workpiece feature to be inspected;
• filtering the first workpiece image using the structuring element, at least in a region including the workpiece feature to be inspected, to provide a filtered image at least in a region including the workpiece feature to be inspected;
• and
• inspecting the workpiece feature in the filtered image, including performing operations defined by at least one video tool which defines a region of interest located proximate to the workpiece feature in the first workpiece image and performing those operations for a congruent region of interest in the filtered image.