Improving the extracting precision of stripe center for structured light measurement

Abstract

The accuracy of the stripe center extraction is affected by the uneven reflectance and large curvature change of the object surface in the structured light three-dimensional measurement system. Aiming to eliminate the stripe distortion and improve the accuracy of stripe center extraction, an improved stripe center extraction method is proposed for structured light measurement. By analyzing the principle of stripe distortion and the types of stripe noises, the mean filtering is used to eliminate the noises. Then, a stripe preprocessing method is presented to adjust the gray scale of stripe distortion. Finally, stripe centers are extracted through the curve fitting method by preprocessing. Furthermore, the proposed method addressed the problem of local discontinuity of the stripe center caused by the unevenness of brightness in the measurement of complex surface profiles. The proposed method has been validated and verified by experiments. A high accuracy in the extraction of strip centers could be obtained.