Graduated Scale Inspection Using Computer Vision

摘要

A method for graduated scale inspection using computer vision is proposed. We deal mainly with the lens distortion problem in the image acquire device due to its influence in the uncertainty of the graduated scale inspection process. This paper presents an algorithm for image correction by means of camera calibration and distortion compensation. The camera calibration method provides the ideal undistorted coordinates of the system using as input distorted images of a 2D calibration pattern. The distortion compensation stage is implemented using the ideal undistorted coordinates as an unwarped mesh. Then distortion compensation can be applied to any image acquired with the system, improving the inspection procedure. Test results using real data are presented. Also, we describe the image feature extraction approach used in order to automate the process.