Spatial moment based line structured light center extraction method

Abstract

The invention relates to a spatial moment based line structured light center extraction method and belongs to the field of laser light ray center extraction methods in the visual and three-dimensional measurement of line structured light. According to the method, an ideal normal equation for a place where an edge point is located is obtained through the gray-level gradient vector of the edge point of a light ray, and one direction, closest to an ideal normal direction, of eight directions of a bisect coordinate system serves as an actual normal direction of a light ray curve, so that a light ray section passing through the actual normal of the edge point and the light ray is obtained. According to the method, an adopted light ray section selection method can better adapt to the drastic change of light ray curvature and can guarantee that pixel points in the light ray section are distributed uniformly, and a closed analytic formula for solving the coordinate of a light ray center point based on spatial moment theory is given and established. According to the method, when a phenomenon that the gray level of the center of the light ray is saturated occurs, serious detection errors cannot appear, so that the aspects, such as the timeliness and accuracy of detection results and the robustness to errors, surpass those of the traditional methods.

Description

technical field [0001] The invention belongs to the field of the extraction method of the center of the laser light bar in the three-dimensional measurement of the line structured light vision, and in particular relates to a method for extracting the center of the line structured light based on the space moment. Background technique [0002] Line-structured light visual three-dimensional measurement technology is a non-contact measurement technology based on optical triangulation, which has been widely used in the field of rapid detection of industrial product appearance. How to quickly and accurately extract the center of the laser light bar in the image is the key factor to determine the measurement accuracy of this method. [0003] The traditional methods for extracting the center of light bars based on image grayscale include gray threshold method, extreme value method, and edge method. The determination of depends on the operator's experience and is not easy to quantif...

AI Technical Summary

Problems solved by technology

[0008] In order to solve the problem that the traditional line structured light center extraction method cannot meet the requirements of visual three-dimensional measurement technology in terms of accuracy, immediacy and robustness to errors, and When there is a large position or the gray saturation phenomenon in the center of the light bar, there are technical problems of serious detection errors. The present invention provides a method for extracting the center of line structured light based on spatial moments

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