Structural body crack sub-pixel detection method

Abstract

The invention relates to a structural body crack sub-pixel detection method, which comprises the following steps of: 1, acquiring a plurality of surface images of a structural body, and recording position attitude information of a camera when each image is shot; 2, performing image correction and image calibration on the shot image according to lens parameters and position attitude information of the camera during shooting so as to obtain a calibration coefficient of a distance from the camera to a shooting plane; 3, splicing the plurality of shot images to obtain a structural body surface expansion view; 4, based on the trained crack image training model, carrying out region segmentation on the structure body surface expansion image, and carrying out crack extraction in different regions; and 5, refining the extracted binary image of the crack, obtaining a crack skeleton diagram, calculating the initial point position information, the end point position information and the bifurcation point position information of the crack, and calculating the sub-pixel width and length of the crack. According to the invention, both efficiency and precision are considered, and the crack parameter of 0.1 pixel can be detected.

Description

technical field [0001] The present invention relates to the technical field of crack sub-pixel detection in structures, in particular to a sub-pixel detection method for cracks in structures. Background technique [0002] Any architectural structure will be affected by the natural environment and human activities, resulting in varying degrees of degradation and decay. Over time, these visible or subtle changes may affect the safety and durability of the structure. In some special fields, such as water conservancy projects, cracks can endanger the safety of dams; in nuclear power plants, defects in the concrete casing of reactors can cause radiation leakage, and defects in air cooling towers can affect production. For some large modern architectural structures such as stadiums, terminal buildings and grand theaters, the decline of the structure is directly related to personal safety. [0003] At present, in China, external methods are mainly used for surface inspection of st...

AI Technical Summary

Problems solved by technology

The traditional edge detection algorithm can only realize the whole pixel detection, that is, it can only detect the edge of the unit pixel level.

The traditional method can only identify crack images whose crack width is equal to or greater than 2 pixels. If the crack width is less than 2 pixels, this method cannot identify cracks, nor can it realize the recognition of sub-pixel crack images.

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