Light spot center detection method

Abstract

The invention discloses a light spot center detection method, which comprises the following steps of collecting a light spot image, and carrying out denoising preprocessing on the image; carrying outcoarse positioning on the light spot by utilizing an edge detection algorithm to obtain a pixel-level light spot edge; performing interpolation operation on the pixel-level light spot edge to obtain asub-pixel-level light spot edge; carrying out refining processing on the sub-pixel-level light spot edge to obtain a refined sub-pixel-level light spot edge; and based on the refined sub-pixel-levellight spot edge, solving a light spot center by utilizing a Gaussian fitting principle. According to the invention, the Canny edge detection operator and the interpolation method are combined, so thatthe Gaussian fitting light spot edge is at the sub-pixel level; the edge information of the image can be reserved to the maximum extent, the false positioning rate is remarkably reduced, the positioning precision is improved, a good positioning effect is obtained, the operation time is short, the real-time performance is high, and the requirement for industrial precision size measurement can be met.

Description

technical field [0001] The invention relates to the field of image processing, in particular to a method for detecting the center of a light spot. Background technique [0002] In the visual inspection system, applying laser measurement to precision dimension measurement can realize non-contact measurement, which can simplify the complex and repeated calibration process of the measurement system in traditional visual inspection. In order to further improve its accuracy, it is necessary to convert the spot Center detection is localized to the sub-pixel level. [0003] The traditional spot center detection methods mainly include gray-scale center of gravity method, circle fitting algorithm and Hough transform method. Among them, the gray-scale center of gravity method is only a better method when the light intensity of the spot is uniform, otherwise there will be a large Error, and the anti-interference ability of the center of gravity method is weak. When there is a certain ...

AI Technical Summary

Problems solved by technology

[0003] The traditional spot center detection methods mainly include gray-scale center of gravity method, circle fitting algorithm and Hough transform method. Among them, the gray-scale center of gravity method is only a better method when the light intensity of the spot is uniform, otherwise there will be a large Error, and the anti-interference ability of the center of gravity method is weak, when there is a certain intensity of interference light, the measurement results are often inaccurate, so the measurement accuracy of the center of gravity method is poor

However, due to the influence of edge noise, the circle fitting algorithm will cause a large difference between the fitted curve and the edge of the original spot.

The Hough transform method is not suitable for real-time detection systems, and the detection accuracy is not high

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