Application of Improved Cubic Convolution Interpolation in Circular Target Location

摘要

The precision of target sub-pixel centroid location directly affects the result of large scale vision 3D coordinates measurement. This paper deeply studies the sub-pixel centroid location algorithm of retro-reflective targets and infrared optical targets used in 3D coordinates measurement system, and makes use of improved cubic convolution interpolation algorithm to increase the number of effective pixels used in centroid location, then gives optimizing adjustment parameters for different types of targets and combined with squared gray weighted centroid location algorithm, finally realizes accurate target sub-pixel centroid location. This algorithm is proved to be effective and robust by simulations and experiments.